Print Page - Poultry Management:

The ABC of male behaviour
By Ron Meijerhof, senior technical specialist, Hybro B.V. Males play an important role in obtaining a good hatchability, because they are of course crucial in the process of getting fertile eggs.

Although it is well known that also female condition can be a significant factor, in case of fertility problems we often look at the males. And most often, that is the correct starting point. If we think about fertility problems, we normally think about factors as semen quality, bodyweight control, physical condition of the males, foot pad quality, etc. Without a doubt, these aspects are important. If semen quality is not optimal because of a disease or a nutritional factor, or if semen quantity is not sufficient because the males lost bodyweight, maximum fertility will not be achieved. If the males lose condition because of overweight or have a problem walking because their foot pad quality is not optimum, it will definitely have a negative effect on fertility. However, there is one more factor that is of utmost importance for fertility.

They have to like each other
The most important factor for a good hatchability is a high number of successful matings. And to be able to have successful matings, not only the physical condition of males and females must be good, but they must also have the will to mate. And as mating is the final result of a complex sequence of social interactions, we have to look at the behavior of the males and females as well, if we want to make sure we have a high number of successful matings. In other words, we have to make sure they like each other.

Male-to-Female interaction
One of the most important aspects in the behavior of chickens is the issue of dominancy and pecking order. A male (chicken) has to be dominant over a female to be able to mate. At the same time, the female should not be scared of the male and try to avoid mating. In a well managed flock, males get dominant over the females just before production starts.

If their dominancy develops too early, the males are getting active before a sufficient number of females is sexually mature, and as a result the males start chasing the females, over-mating occurs, males start fighting with each other, females are getting damaged and scared, and as a final result, fertility is too low.

If their dominancy develops too late, the males will not become dominant over the females and will be scared to mate with them. The males can be physically well developed but will not mate because they think they are not able to do so. And as a result, again fertility is too low.

Male-to-Male interaction
However, there is not only a hierarchy between males and females, but also between the males. Not all males are equally dominant, and some males are higher up in the hierarchy than others. This is often a result of differences in body weight, but is not always necessarily so. If we take a closer look at the flock, we can divide the males in three different groups:

A-males: males that are dominant, high-up in the hierarchy, are willing to mate and will mate.
B-males: males that are not dominant, are not high enough in the hierarchy, but would like to mate and will try to mate if they get the opportunity.
C-males: males that are not dominant, are low in the hierarchy, and are too low in the hierarchy to mate or even consider mating.
Of course this is an arbitrary classification, but it helps us to understand what happens in a flock of males. In an actual flock, all three groups will always be present, but it depends on the condition of the males what the distribution between the groups will be.

It is clear that B-males will be dominant of C-males, and A-males will be dominant over both B and C males. That means that an A-male will try to prevent B-males from mating, although the B-males would like to mate. The problem of a low fertility can be that there are not enough A-males to do all the mating, or that there are enough A-males but they are occupied with other things than mating. Especially if there is high number of males in a flock, sometimes the males are so busy with disturbing each other that the number of successful matings is going down.

Within the flock, it is not only the group of A-males that are mating. Most females will stick for a limited period of time to one male, and that will be an A-male, but some females will move around from male to male, and some females will try to avoid mating by doing that. We can recognize this when we set eggs from individual hens, because we then see that some hens always give infertile eggs and avoid mating. We call these females “loose hens”, and we normally see the number of these hens increasing with the age of the flock. If B-males have the opportunity, they will try to mate with these hens. And the more brutal and brave these B-males are, the more successful they will be in doing so.

Increase fertility
At first sight, the key for a good fertility is a high number of A-males in the flock. What we have to realize is that just taking out the bad males (C-males) will not always solve the problem of bad fertility sufficiently, as by doing this we don’t increase the number of A-males, we just decrease the number of C-males. But the C-males are not the real cause for a bad fertility, because they didn’t mate in the first place. That doesn’t mean we don’t want to select these males out, but we have to realize that these males are not always our biggest problems.

Where we want to focus on is on two different things:
We want to keep the number of active A-males high. Not only should we have enough A-males, but they also should be active, and not only busy with fighting other males.
We want to get the B-males as active as possible, so that as many as possible “loose hens” are mated.
How to manage male behavior in the field?
There are several management tools that we have to take into consideration for achieving these two goals.
First of all we have to look at the male and female behavior, to see how they react towards each other, especially early in production. The best time to look for the behavior is in the last period before the light goes out, as this is the period where the males are most active.
If we look over the flock, we should see the males sticking out over the females as “tulips in a meadow”. This means that the males feel dominant and stand upright, with their backs under an upward angle. If the males don’t stick out 10-15 cm over the females but have their heads on the same height, it means that they don’t feel very dominant, very “macho”, and probably their mating activity will be low.

If we stand in the house for a couple of minutes (especially if we are visitors), males should pay attention to us, and even come up to us. After a couple of minutes, we should see that the females move gradually away, and the males move towards us, so that 1/3 or half of the birds in the direct neighborhood are males. This means that the males see us as intruders in their territory, and they are reacting to that. If males don’t care if anybody comes in their territory, looking for their females, they are probably not that dominant.

The females and males should act “socially” towards each other. If the females try to avoid meeting the males or the males surround and chase the females, they probably don’t like each other that much. If we see this, we should react immediately by reducing the numbers of males, to release the pressure. In early production this often means that we have to get rid of some of the best males, because they are matured too early.
If we rear males in high density (more than 4 birds per m2) they will often run into each other and fight. As a consequence, several males will lose their dominancy and become a C-male already in rearing, because more males will lose fights. If we rear in low density, the males will fight less, and as a result, stay dominant because they never lost a fight.
We have to make sure that the males grow enough early in production, to build up their dominancy. If we don’t allow them to grow or even let them lose weight, they will not be able to keep up their dominancy and will lose mating. Often we see that males become overweight because they are inactive, and not become inactive because they are overweight.
When we select, we should pay attention also on males that act dominant but don’t mate anymore. This can be done by looking at the color and the condition of the cloaca. We should especially examine the males that look dominant, but at the same time are overweight.
When we spike, we have to make sure that the young males have a chance to overcome the A-males. This means that the young males must be mature enough, but that we place enough young males and preferably remove some of the A-males. To select the right males to remove, we have to again look for the dominant A-males that seem to be overweight and have a dry cloaca. Of course we also want to select the non-active C-males, as they are of not much good anymore. If we don’t give the young males a fair chance, they can very quickly be found in the group of C-males.
When we intra-spike, make sure that as much males as possible are moved and mixed between the houses, to break the existing hierarchy.
If we force the males to move a lot through the house, more B-males will mate with “loose hens”, resulting in more mating. This means that we have to centralize the male feeders as much as possible to force the males to move, instead of spreading out the male feeders over the house.
With sex separate feeding we do not only control the male body weight (and with it prevent overweight) but we also make the B-males more courageous and less afraid. This is because we force them to eat together with the A-males every day. It is therefore especially important to not only look at body weight control with sex separate feeding, but also to the location of the feeders. Again, it is important to bring as much males as possible into the same area.
By looking not only at the physical condition of the males but also at the way they act with the females and towards each other, we can learn a lot about their mating activity. After all, if males and females don’t like each other, mating will not happen, no matter how well their physical condition will be.

March 2007

Maximising performance using the broiler breeder’s own agenda
By Ron Meijerhof, Senior Technical Specialist, Hybro B.V. - The technical performance of broiler breeders is influenced significantly by their natural behaviour.

Technical results will be adversely affected, for example, if the birds don’t want to enter the laying nest, mate or they are unable to eat all at the same time – regardless of the genetic potential of the birds. So to manage our breeders for optimum performance, it helps to understand the ‘behaviour basics’ that are incorporated into the daily schedule of a chicken.

Creatures of habit
Broiler breeders don’t perform their activities randomly throughout the day. They have a schedule, the most important aspects of which revolve around egg laying and mating, which we must respect through our management practices.

Egg laying
Laying begins about one hour after the light goes on in the morning, with the majority of eggs being produced in a period of approximately six hours. This means that throughout that six hour period, all birds must have unhindered access to the nests.

A broiler breeder will often occupy the nest for about 45 minutes to lay her egg, with around 20-25 minutes to prepare for laying, and another 20-25 minutes to enjoy the result. In warm conditions, birds may occupy the nest for even longer.

If we consider the fact that not all birds lay every day, and that not all nests are occupied 100 per cent of the time, we can calculate at least one hour of nest occupancy for every egg laid, in a laying period of about six hours. This means that at peak production, we need one individual nest per five or maximum six birds.

In a community nest, each laying bird will occupy around 15cm width in the nest – so approximately six birds per metre of nest space. And if each place is occupied for one hour, we can expect to place 35-40 birds per metre of nest length during the six hour laying period. Placing more birds is likely to be counter-productive, as this will make it difficult for some of the birds to find a free space.

Mating
Mating is, of course, a key feature of the breeder’s daily schedule, occurring mainly during the last four hours of light – and with good reason. If mating happened in the morning, the laying of eggs would obstruct mating behaviour, and the outgoing egg would expel incoming semen.

Males are most active during this part of the day, so we must attract the females to the scratch area during this time, as well as observing the mating behaviour of the males, to ensure that they are neither too aggressive nor too docile.

Feeding and drinking
With the first six-seven hours and the last four hours of a 16 hour light so engaged, we are left with only five-six hours during which to plan eating and drinking.

If we provide feed during egg laying or mating, we are effectively asking the birds to choose between staying hungry to use a nest or mate, or to take feed with the risk of producing a floor egg or avoiding mating. And some of our breeders will choose to eat!

Depending on the flock and the feeding system, birds need approx. two hours to eat and four to drink. This means that we should start giving feed and water seven-eight hours after the light goes on, to avoid any conflict with laying and mating behaviour.

Another advantage of feeding after laying, is that the calcium in the feed becomes available for the bird when shell is formed, mainly during the night.

However, if we feed seven-eight hours after lights on, digestion will occur during the warmest hours of the day. This is not a problem in moderate climates, but the heat production associated with digestion can cause problems for birds in hot climates – where to ensure that feeding doesn’t interfere with laying, we must compensate by feeding as early as possible.

Our breeder flocks have a very straightforward approach to life, and therefore to what they need and expect from us. By understanding their behaviour and meeting their expectations, we can ensure that our birds make choices that are in our best commercial interests.

May 2007

Feeding Broiler Breeders for Chick Quality
By Aviagen - For a chick to fulfil its genetic potential as a broiler chicken, it is imperative that it has the best possible start in life.

Introduction
For successful broiler production a chick requires good bodyweight, with excellent nutritional reserves at day old. It needs to be in excellent health with a fully functioning immune system. From this starting point, providing the broiler with suitable environment and nutrition will enable optimal performance to be achieved.

The developing embryo and the hatched chick are completely dependent for their growth and development on nutrients deposited in the egg. Consequently the physiological status of the chick at hatching is greatly influenced by the nutrition of the breeder hen.

In reviewing breeder nutrition, it should be remembered that nutrient supply to the broiler breeder is a sum of two parts, namely nutrient content of the diet and quantity of feed supplied to the breeder birds. Both parts need to be balanced to ensure correct daily nutrient supply. It is also very important to realise that the cost of feeding the breeder appropriately to ensure good nutritional status of the chick is very low when viewed on a per chick basis and compared with the total feed cost of raising a broiler to slaughter weight. Calini (2006) calculated that the cost of breeder feed contributing to the production of a chick is equivalent to only 7% of the total feed cost for a broiler grown to 2.5Kg. This illustrates the value of ensuring the best possible nutrition of the breeder.

Nutrient Levels in Broiler Breeder Feeds
When considering nutrient levels in breeder feeds, the nutritionist must focus on the daily supply of individual nutrients to the bird. Starting with protein, studies have shown that the protein levels fed to breeders in production can affect chick bodyweight and final broiler performance. The relationship between protein content of breeder feed and chick weight seems well defined.

Using this information, a breeder diet with an energy density of approximately 2750 Kcal/Kg should have a protein content of 15%. This optimum protein level has been supported by other work, and it is important to remember this is an optimum level, not a minimum, as excess protein can be as detrimental as insufficient protein. In particular, it has been shown that excess protein reduces fertility. Furthermore, consideration must be given to protein quality and the nutritionist must ensure a balance of amino acids is supplied from good quality protein sources.

The impact of energy content of the breeder feed is not as well defined as that of protein. Reviewing studies carried out to evaluate optimum energy intake would suggest that 440 - 480 Kcals/bird/day is most appropriate for optimal chick quality. This equates to 160 - 175 g/bird/day at 2750 Kcal/Kg feed. When considering energy, attention must also be given to fat composition and in particular to the requirement for unsaturated fats such as linoleic acid. This essential fatty acid is required for cell membrane integrity, immune competence and embryonic development, therefore directly affecting chick quality. In practical terms, the inclusion of added fats into breeder feeds should be kept low, with preference for unsaturated fats rather than saturated fats.

The major minerals, especially calcium, phosphorous, sodium, potassium, magnesium and chloride are involved in shell formation; improvements in shell quality generally lead to better egg and chick quality. Variations in maternal phosphorous supply have been shown to influence bone ash of young but not older progeny. It is important to supply adequate phosphorus in breeder diets to ensure best possible bone integrity in the early stages of chick growth. In terms of trace minerals, most interest in this field has centred on the use of chelated minerals which have been shown to increase deposition in the egg and transfer to the tissues of the hen and the embryo. Most recent work has focused on the antioxidant status of breeders, embryos, offspring and the role of selenium. Seleno-methionine has been shown to improve both the vitamin E and antioxidative status of eggs, embryos and chicks up to 10 days of age. Supplemental zinc methionine and manganese amino acid complexes have shown improvements in chick immunity and liveability.

Table 1 is a summary of those minerals which when fed to breeders have an effect on progeny performance.

Table 1. Summary of minerals fed to breeders shown to have an effect on progeny performance.

Growth
Liveability
Immune Function
Skeletal

Fluoride

X

Phosphorous

X

Selenium

X

Selenomethionine
X

X

Zinc
X

X
X

Zn-Methionine

X
X

Vitamins are involved in most metabolic processes and are an integral part of foetal development, therefore the consequence of suboptimal levels of these nutrients in commercial diets are known to result in negative responses to both parent and offspring performance. Vitamins account for about 4% of the cost of a breeder feed, so economising on vitamin inclusion rates is rarely a sensible option. Generally there is a shortage of information on vitamin requirements of broiler breeders especially when related to offspring performance. Most of the breeder work is quite dated and since that time breeder performance has changed.

A review of work on fat soluble vitamins, biotin and pantothenic acid has shown that vitamin E has the largest impact on progeny. In general it seems to be justified to supplement practical breeder feeds with 100 mg/kg vitamin E.

The influence of increased vitamin levels fed to young parent stock on progeny performance is an area which has received significant commercial interest. Internal and field trials have shown that increased vitamin levels (mainly B Vitamins and Vitamin E) improved liveability and early growth. A practical basis for making recommendations is to feed vitamin levels that maximise the resulting level in the egg.

The Influence of Feed Allocation on Chick Quality
Underfeeding the hen can have an impact on chick quality and this is particularly noticeable in the early production period. Modern hybrid parent flocks commence production at a faster rate than in the past and consequently egg output increases over a shorter time span during the early laying period. Feed allocations during this period have not necessarily increased in line with this egg production trend. Low feed allocation intake by young commercial breeder flocks have been shown to compromise nutrient transfer to the egg, resulting in increased late embryonic death, poorer chick viability and uniformity (Aviagen Ltd 2002). In a study by Leeson (2004) broiler breeders were fed different levels of feed through peak production varying from 140 to 175 grams. Although the increased feed allocation increased bodyweight there was no influence on egg size up to 175g, however chick weight was influenced by feed allocation. See Table 2 below.

Table 2. The effects of breeder feed levels on chick weight

Peak breeder feed (g/b/d)
30 week breeder chick weight (g)

140
40.3

147
40.0

155
41.5

162
41.7

169
41.8

175
42.0

Summary
Research shows that nutrient supply to the broiler breeder is of consequence to chick quality and production performance. This places greater emphasis on the nutritionist providing the correct nutrient density diet and the flock manager to provide appropriate feed intake to the bird coming into lay and through the production period.

4 Key Points
Breeder Nutrition influences chick quality and broiler performance

Broiler performance can be economically improved by investing in breeder nutrition

Supply diets with adequate and consistent nutrient levels to breeders

Manage feed quantities with reference to breeder physiological requirements, productive status and bodyweight
March 2007

Rearing Parent Stock
By Johnny Harrison, Technical Service Manager, Aviagen Limited - This article follows the life of a flock of Aviagen parent stock birds, focusing on the rearing period, 0 - 6 weeks, (0-42 days).

Aviagen produce a range of genotypes suitable for different sectors of the broiler market and all Aviagen products are selected for a balanced range of parent stock and broiler characteristics. To achieve the best possible outcome, and to meet the needs of your operation, the best possible start must be provided to both the male and the female parent. Fulfilling all of their requirements during the rearing period will prepare them for sexual maturity.

Aviagen parents have the same growth and feed efficiency characteristics as the broiler generation, so growing the Aviagen parent to the target growth curve allows both males and females to achieve optimum lifetime breeder performance. The principles for managing males and females in the rearing period are the same, even though the target body weights are different. Although males constitute a small percentage of the flock in terms of bird numbers, they will form 50% of the breeding value. Males are therefore just as important as females; however throughout the rearing period the management of males will require more effort to achieve success.

Managing the available feed is crucial in ensuring even distribution to all of the birds and this is one of the main management challenges during rear. Managing the birds' growth rate so they achieve the target bodyweight for age is maintained through accurate control by sample weighing at least twice a week until grading and adjusting feed allowances accordingly. As a result accurate grading will aid good uniformity.

HOUSE PREPARATION

FIGURE 1: Bird Distribution under Brooders
As outlined in the Biosecurity article (Zootecnica Russian Edition, Feb/Mar 2006), houses and equipment must be cleaned, disinfected and set up in time for the brooders to be started and temperatures to reach the desired level 24 hours before the chicks arrive. The house should be checked to ensure that it is adequately light proofed. Birds are very sensitive to day length and any accidental seepage of light should be corrected immediately. Match the times when house lights are on to the natural day light as far as possible to limit the impact of poor light proofing. Problems such as early on set of lay, broodiness and prolapses or delayed production may result from poor light proofing of the rearing house.

Temperatures should be checked at chick level. If insufficient time is allowed for floor temperature to reach house temperature, there is a danger that the chicks will become chilled. Chick behaviour is the most important indicator of temperature, farm managers and farm staff must respond quickly to changes in chick behaviour. The photo right demonstrates chick distribution.

Fresh litter, free from dust, should be laid to a depth of 10cm. Where floor feeding is in use litter depth should not exceed 4cm as feed will be lost in the litter. Good quality litter will reduce the risk of the chicks eating the litter.

BROODING AREA PREPARATION
There are two basic systems to supply heat to the birds:

Spot Brooding
Warm air/Whole House Brooding
Brooding down the centre of the pen is most likely to achieve uniform chick distribution. Figure 2 shows a typical spot brooding system for 1000 day old chicks. When planning chick placements, it is advisable to brood chicks from young donor flocks separately for the first 14 to 21 days, this will prevent early competition when birds are unequal in size.

On both systems chicks must be placed in the brooding area immediately after they arrive. Full chick boxes should never be stacked within the brooder house as this can cause heat stress. Empty chick boxes should be removed from the building and destroyed as soon as possible. To avoid undue stress vaccination should take place in the brooding area after the chicks have settled in.

The brooding area should be designed to allow the chicks access to a plentiful supply of fresh feed and water upon arrival. Birds given immediate access to feed and water have been shown to have better early growth and uniformity than birds in which feeding was delayed.

A maximum of one day's supply of feed should be provided daily to avoid problems associated with stale food. Chicks should be treated as broilers for the first 5 to 6 days (i.e. fed ad libitum). Feed should be given frequently (i.e. 5-6 times per day) to stimulate appetite.

A plentiful supply of water must be provided, use supplementary drinkers as well as the drinking systems already fitted in the house. Aviagen does not recommend the addition of glucose to drinking water as it can depress appetite and cause dehydration; the goal we are aiming for is developing healthy appetite and drinking behaviour

For the first 24/48 hours light should be continuous, with a light intensity of 100 lux. To encourage even distribution of chicks, the brooder light should be raised initially, followed 2-3 days later by switching on the adjacent rows of house lights.

The principles for whole house brooding are basically the same, but it is less easy to use chick behaviour as an indicator of satisfactory temperature than with spot brooding, because there are no obvious heat sources. By spending time in both environments you will notice a different noise made by the birds, this may be the only indication of distress. The birds will congregate in the areas where the temperature is closest to their requirements. Some care is needed to interpret chick behaviour.

Chicks must have an adequate supply of fresh air and a minimum ventilation program must be established during brooding. It is good practice to establish a system of minimum ventilation during brooding.

Monitor relative humidity (RH) levels in the first 3 days and aim to achieve around 70%. If humidity falls below 50%RH in the first week, chicks will begin to dehydrate, causing negative effects on performance. In such cases, take action to increase humidity. Various methods of humidification are suitable, from spray systems designed to cool birds in hot weather to simple open water surfaces. Keep the system clean, because it can provide a very effective means of transmitting bacteria.

REARING FROM 0 - 4 WEEKS (0-28 DAYS)
The aim in this period is to ensure good early development of skeletal size, immune system, cardiovascular function, feather growth and appetite. It is important to obtain the best possible uniformity to reduce the amount of size grading required later in the flock.

To maximise performance birds should be on or over target bodyweight by 7-14 days. Flocks that fail to achieve target tend to lose uniformity. Bodyweight targets in the early stages of rearing can only be achieved by ad libitum feeding of a good quality feed from day old, Crop fill should be assessed to ensure that chicks are developing a healthy appetite and achieving good early bodyweight and skeletal growth, see figure 4.

A full crop will be a rounded mound and it should feel like pea soup, a mix of water and feed. Aim for more than 95% of birds with full crops by 8 hours after first access to feed and water, and more than 99% at 24 hours.

If there is any evidence that birds are not growing to target bodyweight, then the age at which constant day length will be achieved can be delayed

BODYWEIGHT AND UNIFORMITY
It is essential to monitor growth and development in a flock by weighing an adequate sample of birds and comparing them with the target bodyweights-for-age. The birds must be weighed accurately using conventional mechanical, dial or electronic scales are more labour intensive, but using these systems enables you to handle each bird and check its condition as well as its weight.

Sample weighing should be carried out twice weekly starting at day old; randomly selected samples of birds should be weighed individually. Groups of 50 to 100 birds per colony should be caught using catching frames and individually weighed. All birds rounded up as a sample must be weighed in order to eliminate any bias. Birds should be weighed on the same day each week and at the same time, preferably 6 hours after feeding

CONTROLLING BODYWEIGHT
Bodyweight can be corrected by adjusting feed allowance. This can either be maintained or increased. Feed allowances must never be decreased during the rearing period. Adequate feed space must be available and feed should be distributed in less than 3 minutes per colony. Good feed distribution, which allows all the birds to have access to feed at the same time, is absolutely essential because the birds are fed at less than ad libitum.

Birds must be fed every day until grading has been carried out. After grading an alternative method should be considered to ensure even distribution of the feed, minimising competition and maintaining bodyweights and flock uniformity. 'Skip a Day' can be used. This is achieved by accumulating sufficient feed on the 'feed day' and supplementing with a scratch feed on the intermediate days.

GRADING TO MANAGE UNIFORMITY
Uniform flocks will be much easier to manage than an unequal one, because the majority of the birds will be in a similar physiological state and will respond to changes in levels of feed or light when necessary. A uniform flock will react predictably to increases in feed and will produce good results consistently. Flock uniformity can only be achieved by applying high standards of management in the first 4 weeks.

Grading is best carried out when the flock is aged 28 days (4 weeks), at which time the uniformity of the flock is usually within the range 10-14%. If undertaken later than 35 days (5 weeks) the time available in which flock uniformity can be restored, i.e. up to 63 days (9 weeks) becomes too short. In most cases, grading will be undertaken when the flock CV% is around 12.

The practical requirements of grading must be considered at the planning stage, before the stock is placed. The easiest way to grade is into pens or possibly houses which have been left empty at placement for this purpose. To establish successful grading the flock should be sorted into populations of different average weight at 28 days (4 weeks) of age, so that each group may be given the management during the rearing period, which will result in good whole flock uniformity at point of lay. As an example, separating 10,000 females into 4 groups of 2500, less any mortality, will give one group of small birds, two groups of medium birds and one of large birds. The males should be divided into two colonies as it is easier to manage small colonies.

Within the flock to be graded all colonies must be sample weighed and all the individual weighings should be consolidated into a single distribution. Two-way grading is preferable, provided that the flock CV% is less than 12 at grading. If the CV% is more than 12, then a 3-way grading will be required and management practices from 0-4 weeks should be examined closely, so that improved CV% can be achieved with subsequent flocks.

Flock CV% should be calculated. Cut-off points must be set to achieve consistent stocking densities allowing for differences in pen size. Table 2 indicates the typical percentages in light, medium and heavy populations to achieve populations with CV % less than 8 for 2 or 3-way grading. Bird weight cut off points should be set to achieve the required percentage of the population in each colony

All birds must be handled and allocated to their correct category to achieve accurate grading. It is strongly recommended, for reasons of efficiency and accuracy, that all birds should be weighed.

Birds must be counted accurately in order that the correct quantities of feed are provided. Stocking density per colony, and therefore feed and water space must have been routinely adjusted when the moveable partitions were positioned. In addition feeding space, speed and uniformity of feed distribution must be adequate.

Each category should be reweighed to confirm the average bodyweight and uniformity so that its projected target bodyweight and feeding rate may be determined.

Key Points:
Prepare, clean and disinfect houses and equipment well in advance of chick arrival.
Ensure that the house reaches the correct temperature and Relative Humidity 24 hours before chicks arrive.
Ensure that chicks have immediate access to fresh water and feed.
Monitor crop fill to ensure chicks are feeding.
Use chick behaviour as an indicator of satisfactory brooding temperature.
Achieve early bodyweight targets to facilitate successful rearing.
Start sample weighing at day-old.
Weigh birds at the same time each week, twice weekly.
Use accurate bird weighing equipment.
Never decrease feed allowance during rearing. Feed allowance should either be held or increased.
Give birds the correct feeding and drinking space.
Feed should be distributed in no more than 3 minutes per colony.
Grade into 2 colonies if CV% is less than 12; into 3 colonies if CV% is greater than 12.
After grading, each colony should have a CV% of 8 or less.
This article was first published in Zootecnica Russian Editon, April/May 2006

Defining and measuring quality in day old broilers
By Ron Meijerhof, Senior Technical Specialist, Hybro B.V., Boxmeer, The Netherlands - The quality of the day-old chick is important not only for minimising mortality in the first days of life, but also as an indicator of final performance.

This means that incubation must not only produce as many chicks as possible, but they must be of superior quality to contribute to commercial success.
However the concept of ‘quality’ is often subjective. Every hatchery manager has his or her own definition of what constitutes good chick quality, which can be difficult to describe – and even more difficult to measure.

Visual score
While visual scoring, ie. as ‘good’, ‘average’ or ‘poor’, is highly subjective, it is nonetheless a relatively accurate indicator of chick vitality. Visual scoring measures:

Colour: a deep yellow colour is favoured over pale (light yellow to white).
Development: a large, well developed, long feathered chick is considered ‘better’.
Navel quality: well closed navels reduce the risk of infection and mortality.
Vitality: alert, healthy chicks will find feed and water more quickly.
Although an experienced hatchery manager may be highly accurate in his or her visual scoring, this system is devalued by being prone to personal interpretation and difficult for other personnel to reproduce.

Tona or Pasgar score
The University of Leuven recently developed the Tona score, which was adapted by Pas Reform to create the simpler and more practical Pasgar score. Both methods apply a standardised scoring system across a range of criteria, including chick viability, yolk sac uptake, navel closure, and the ability of the chick to recover after being placed on its back, for example.

Both methods create a consistent, measurable data-set that can easily be repeated. And while the relationship between Tona- or Pasgar score and broiler performance has not yet been proven, it appears likely that there is a valid correlation to first-week survival.

Day old chick weight
Although easily recorded and repeated, day-old chick weight has limited value as an indicator of overall quality, as it is correlated with egg weight rather than chick development. This is because day old chick weight includes both the actual chick weight and the weight of remaining yolk residue. Yolk-fat is fuel for embryonic development, so if a lot of yolk remains, less development has occurred and chick quality is likely to be undermined.

Yolk free body mass
Yolk free body mass (body weight without residual yolk) is a better indicator of chick development, especially when corrected for initial egg weight . However, measuring in this way is a costly and labour intensive process.

Chick length
Measuring length from the tip of the beak to the middle toe is a more practical way to determine chick development. Hybro’s research has shown that measuring the length of a chick is a dependable indicator of development and a better indicator of broiler performance than day-old chick weight, especially when corrected for egg size.

Choosing a scoring method
The Tona- or Pasgar score and chick length have clear advantages in terms of repeatability, practical application and their relationship to chick quality. However, it is important to note that these two methods are taking different measurements.
As hatcheries are often accountable for first week mortality, the Pasgar score is useful in this environment, as hatcher conditions determine navel closure, yolk uptake and vitality – and therefore the condition of the day-old chick and its ability to thrive in the first week.
Chick length deals more with development, which is related to conditions in the setter, and has less influence on first-week survival but more on performance during grow-out. This method is therefore recommended for total integrations whose bottom-line is determined by broiler performance.
A combination of the two methods, with ± 75 per cent of the final score based on broiler growth potential (chick length) and the balance based on survival rate in the first week (Pasgar score), provides optimal measurement of chick quality.

This column was published in International Hatchery Practice Volume 19 Number 7, 2005

Source: Hybro B.V. - June 2006

Guide for Prospective Contract Broiler Producers
By Dan L. Cunningham, Department of Poultry Science, The University of Georgia - Georgia ranks as one of the top poultry growing areas in the United States, producing more than 7 billion pounds of chicken meat annually.

Introduction
Georgia ranks as one of the top poultry growing areas in the United States, producing more than 7 billion pounds of chicken meat annually. The state's broiler industry has experienced impressive rates of growth since the 1950s. During the 1980s and 1990s, it was not unusual for this industry to grow at annual rates of 5 -7 percent, leading to the addition of many new production facilities. In recent years growth has been in the 3-5 percent range because of the economic downturn experienced in the United States and world markets. As the economy improves, growth of the broiler industry should recover as consumers continue to demand this high quality, inexpensive food item. As a major supplier for U.S. and world markets, Georgia will continue to benefit from this important agricultural industry.

Because of the unique structure of contract poultry farming and its long-term investment, new broiler producers should understand its financial and managerial requirements before they commit resources to this endeavor. The information in this bulletin will help those considering poultry production as a new enterprise.
Structure of the Broiler Industry
The broiler industry is rapidly changing and highly technical. It is "vertically" integrated, meaning that all or most production aspects are owned and controlled by an individual company called an "integrator." Integrators usually own the breeder flocks, hatcheries, feed mills and processing plants and contract out the growing and egg production flocks to farmers. The integrator provides a contract producer with the chicks, feed, medication and technical advisors to supervise farm production. Under this system, the company retains ownership of the birds and expects producers to grow their flocks under very specific management programs. Company field representatives normally visit farms weekly to assist with management, but they may do so more often if necessary.

Vertical integration reduces product costs through coordinating and professionally managing each production stage. This approach not only improves cost efficiency, but permits the production of more uniform birds in large volumes necessary to successfully compete in the market. In this system, the integrator is responsible for all processing facilities, processing labor and salaries, and marketing activities crucial to the success of the poultry business. Processing and marketing are very specialized and require considerable expertise and experience for success. For this system to work effectively, integrators and producers make significant contributions to the process and depend on each other.
Broiler Production Contracts
It is virtually impossible to be in the broiler production business today without contracting with a poultry integrator. Production contracts are written legal agreements between integrators and producers defining the terms and conditions affecting producer payments for production of poultry. In the contract system, the producer provides land, labor, housing and equipment, utilities and litter. In return for these production inputs, producers receive a payment based on pounds of live birds produced. Also, contracts usually provide bonus incentives for superior bird performance. Most integrators use a competitive system that ranks growers based on an average production cost per pound for all flocks sold during the same week. Above average producers receive above average payments while below average producers receive less. The contract system has ad-vantages and disadvantages. One of the key advantages for producers, however, is the shift of a significant portion of production and market risk to the integrator. Contract poultry producers are somewhat insulated from price fluctuations in the poultry markets and, since they do not own the birds, have less capital at risk. Prospective producers should understand there are risks as variations in bird placements, size of birds produced, performance and disease problems can cause fluctuations in producer incomes and profit.
Financial Considerations
Costs for broiler production facilities represent substantial investments for producers. Costs for new housing including site preparation, construction, equipment, wiring and plumbing often exceed $170,000 per house. Generally a minimum of two houses is required to make a production unit, but farms consisting of four or more houses are the norm. An average producer can easily have a $600,000 or more invested just in housing and growing equipment.

Prospective producers should understand that poultry houses are long-term investments. Although construction and equipment loans are usually amortized over 15 year periods, the physical life of the broiler house structure can be as much as 30 years or more if it is well maintained. The life of equipment is much less and it is replaced periodically as it becomes worn or obsolete. The history of the poultry business is one of rapidly-changing technology, so producers can expect that significant upgrades will be necessary during the life of the production facility. Staying current with new technology is generally required to maintain competitiveness and the long-term value of the production facility. This is true not only for poultry, but for most any business enterprise that is going to be successful over time.

Broiler production facilities generally range from 20,000 to 25,000 square feet in size. Depending on the weight of the bird produced and the number of flocks per year, gross income for average performance producers for a 20,000 square foot broiler production facility may range from $34,000 to $40,000 annually. Annual fixed and cash costs per broiler house can range from $28,000 to $30,000, depending on type of house, interest rates and mortgage structure. Thus, cash returns to an average producer's land, labor and management per house are generally moderate ($6,000 to $12,000 per year) during the 15 year mortgage payment period. During this debt retirement period, most producers will need additional sources of income for living expenses while equity in the poultry house is being accumulated. It is important to keep in mind that, in addition to the cash returns, producers also receive returns from their houses in the form of accrued equity. The ability of poultry farmers to obtain financing and build assets over time by virtue of the stability of income provided by contracts is one of the benefits of this system. Once the facility is paid for, cash returns per house become much more substantial and may then be in the range of $22,000 to $25,000 annually. Many factors can affect the cash flows and profitability for broiler farms. Some producers will do better at times while others may not do as well. The figures presented above are intended as a guideline to provide an example of what an average producer might expect to achieve. More detailed information on costs and returns for broiler operations is available through other sources (see recommended reading list).
Steps before Building
Meet with poultry company personnel and other producers to discuss the business aspects of contract production. Study contracts carefully and be sure you understand all aspects of contract production. Realize that you cannot depend on being an above average producer every flock. Flock performances vary even with good management, and individuals will sometimes need cash reserves or other sources of income to cover low pay periods. The financial fluctuations associated with poultry production are, however, generally less than for other agricultural commodities and represent one of the key factors in the stability of this enterprise.
An agreement with a poultry company to grow chickens will be necessary before financing or building of production houses can begin. Generally, companies require new production facilities to be in close proximity (25 to 35 miles) of complex operations such feed mills, processing plants, or hatcheries. This reduces expenses of feed delivery, chick delivery and live haul to the processing plant. Experience with growing chickens is not absolutely necessary for obtaining a contract, but certain producer characteristics ( see summary) may be essential.
Meet with lending agencies to determine the availability of financing, interest rates, and payment schedules. Make realistic cash flow projections to determine feasibility of meeting financial obligations. Producers need to consider the consequences of below-average performance as well as average and above average projections.
All new construction must meet state and local laws regarding zoning and environmental impact. Discuss building plans with appropriate authorities before proceeding. Poultry facilities must conform to industry and company standards. House design and equipment recommendations vary by company preference, and their technical representatives will provide detailed information for new buildings. It is recommended that the most current and widely accepted house design and equipment be chosen to allow the producer the option of growing for other integrators in the future.
In some cases, purchasing an existing production farm is a good way to enter the business. This approach also needs careful consideration before making a commitment. Location of the farm, condition and age of the housing and equipment, and purchase price of the farm are very important. Potential buyers should obtain the contracting company's thoughts on the future and productive potential of the farm and what improvements, if any, would be necessary for the company to continue placement of birds in the facilities. Potential buyers should keep in mind that cash flows from the poultry facilities may not be enough to support the purchase of non-production related assets such as dwelling house, barns, trucks, tractors, etc.
Management and Flock Care
Poultry companies have very specific management programs that producers are expected to follow as part of their contractual obligation. To ensure proper management, companies provide field service representatives to work closely with producers on a regular basis. Producers and company field representatives work together to implement best management programs and achieve the highest flock performance levels possible. This benefits the company as well as the producer.
Maintenance for buildings and equipment is a constant job. As houses and equipment age, maintenance requirements for production facilities generally increase. Producers need to handle as much of the maintenance and repair work as possible, since hiring this type of work can be expensive and can substantially increase the cost of farm operation. Preventive maintenance on ventilation, feeding and watering equipment is essential for extending the productive life of these systems and must be done routinely.
House preparation prior to receiving birds is a very important producer management function as the first few days are critical to flock performance. Such preparation includes cleaning and disinfecting the house, spreading litter, setting up brooders, preheating the broiler house to the proper temperature, and being sure feeding, watering and ventilation systems are working properly. Establishing a good brooding environment before chicks arrive is more likely to ensure a successful flock.
Once birds are placed, a considerable amount of time is required for flock management activities such as collecting and disposing of mortality; keeping flock records; monitoring feed, water and environmental control systems; as well as observing for possible health problems. These activities must be done each day throughout the production cycle, but they generally require more time during the critical first two weeks of brooding. Any problems with the flock should be reported immediately to the company representative.
Disease prevention and control are important flock management factors. To protect the flock, access to the poultry house must be limited to authorized personnel. Producers should avoid visiting other poultry farms and eliminate any contact with other poultry, especially hobby, exhibit and backyard flocks. Decisions related to medications of flocks for disease problems or vaccination programs for disease prevention are company responsibilities and are done only as prescribed by company representatives.
Producers are responsible for disposal of all dead birds according to state approved methods. In Georgia, several disposal options are generally available to producers. The more common methods include burial pits, composting, incineration and rendering. Company representatives or local county extension agents can advise producers on the most appropriate methods for their situation.
Producers are responsible for maintenance of grounds and access roads around poultry houses. Keep weeds and grass mowed to reduce rodent and other pest problems. Areas around houses need to be well drained and roads need to be maintained for easy access to feed bins and load-out areas.
Do not use chemicals, pesticides, herbicides, insecticides, vaccinations or medications in or around poultry houses without company approval.
Other Considerations
Consumer demands and market conditions can change company production and marketing strategies. Changes in company strategies in these areas can cause changes in bird placement schedules and sizes of birds grown. These situations can and do cause variations in producer income. Producers should, therefore, be prepared to periodically experience lower than expected incomes from their production units.
Environmental management practices related to litter utilization, dead bird disposal, air and water quality, dust, odor, and pest control are very important aspects of maintaining a viable poultry operation. Current management practices can generally handle these concerns for most farms. Poultry producers should understand, however, that environmental pressures on agriculture are likely to continue and may lead to increased costs of business for both producers and integrators.
Disposal or utilization of poultry litter is a major consideration for poultry farms. Broiler houses generally produce 130-150 tons of litter material annually. In Georgia, most of this material is used as a fertilizer and soil amendment. Producers are, encouraged to develop litter utilization plans before building houses to ensure environmentally sound application or disposal of these products. Company representatives or University of Georgia extension personnel can help with these plans.
Additional equipment such as a tractor with a front loader, a manure spreader, a truck or other specialized equipment may be necessary depending on the size of the operation and the type of management plan employed. Additional expenses for these pieces of equipment may need to be factored into budget projections.
Vacations and time off have to be scheduled around production cycles. Once birds are placed in the houses, they require constant care and management. Achieving good performance levels and above average pay out requires attention to details, and most producers feel they must remain close to their farms during this period.
Develop and maintain friendly relations with your neighbors. Offering to supply manure for a garden plot each year or some other benefit can go a long way when their support is needed.
Summary
Contract poultry production has been a good business for many Georgia farmers. Growing chickens, however, is not for everyone. Before deciding to become a contract producer, determine whether or not you possess the attitudes and capabilities to be a successful producer. A prospective producer needs the following attributes:
A desire to raise chickens.
The financial capability to build housing.
Adequate land for placing the house and disposing of litter.
Adequate and dependable labor.
A willingness to meet contractual responsibilities.
A mind for business.
An open mind to accept technological changes.
A willingness to work within an integrated approach to production.
Once you decide you are interested in contract production, contact companies within your area to determine if they are interested in adding new producers. Get copies of the companies' specifications for buildings, equipment, scheduling and contracts. Discuss broiler production with company representatives. Do not invest in land, buildings or equipment until you have written assurance from a broiler company that you will be provided a contract.

Visit producers who are currently contracting with the company in which you are most interested. If possible, work with an experienced producer for a few weeks to determine if you are suited for the type of work and hours involved. Before building, design a litter utilization and dead bird disposal plan to meet your production plans and farm situation. Keep in mind possible expansion plans for the future of your farm. Talk to your neighbor about your decision. Do you have their support or will neighbors become a major problem?

Talk to local authorities regarding any zoning restrictions or ordinances that might affect your plans. Discuss your plans with lending agencies to determine potential for financing. Visit and discuss your plans with your county extension agent and extension poultry scientist. Obtain copies of extension publications on broiler production and management from your local county extension office or the Department of Poultry Science, The University of Georgia (see recommended reading list).

Making a good decision on broiler farming depends on obtaining as much information as possible. The more people you talk to, the more knowledgeable you will become. Broiler production today requires a substantial investment of funds as well as a major commitment to a life style. It can be an enjoyable and rewarding lifestyle if the decision is made with the appropriate knowledge.

Source: University of Georgia - Cooperative Extension - April 2006

The Management of Male Breeders
By Lindsay Broadbent, UK Customer Account Co-ordinator, Aviagen - The objective in managing male breeders is to rear sufficient good quality males to mate with females at 19 weeks and thereafter maximise fertility through the lay period. Good quality means that males have the potential to maintain high levels of fertility through the production period. Sufficient will mean anywhere between 8 and 10 percent of the female number at 23 weeks.

From evidence we have collected in the UK and other information available, the emphasis on managing the male breeder has changed from a blinkered view of absolute weight profile to a combination of weight profile, skeletal size, uniformity, body condition and mating ratio.

The key message is that weight and feed profile increase from day old to depletion. The weight profile in lay has been modified to ensure that the correct growth rate is more easily achieved and to ensure that body condition is not compromised with age.

Early Growth
It is important that the chicks start well, a good quality starter crumb to 14 days then a starter pellet through to 6 weeks. Weight targets must be met through 7, 14, 21 and 28 days if the birds are to develop good early frame size, feather cover, cardio vascular and immune systems (Fig. 1). A sound skeleton set here will be the building block for the mature male in the breeding house. If weight profiles are met by 28 days, the uniformity will be maximised and the requirement for grading in the following weeks will be minimal.

It is good practice to select the candidates for mating up at 5 weeks. Selection here for a tight population of 100% evenness (CV of 5-7%) to carry forward to the breeding house, plus a few spares for unforeseen losses. Any birds with leg or skeletal defects should be removed here along with undersized and poorly feathered birds. Maintaining uniformity from this point requires the correct stocking density, feed space and feed allowance. If required a second grading at 10 weeks may prove useful. But after this time there is no benefit in grading as the skeleton is 85% grown and leaves no opportunity for the manager to influence skeleton size further.

Stocking density in the range of 3-5.5 birds per m2 is optimal. Feed space from here on must increase up to 10cm per bird if fixed systems are used, then to 15 cm by 10 weeks and 18 cm at 15 weeks.

From 10 weeks, it is critical that you do not lose impetus in growth rate. Development of the sertoli cells begins around this time and testes development continues through to sexual maturity at 23 weeks. From 15 weeks there is rapid development of the testes and growth profiles must be followed or fertility will be delayed or lost. (Fig. 1)

Because of the continuing selection for feed efficiency in male lines, you may need to use a more dilute, bulky diet to increase feed volume in mid rear to ensure adequate intakes of nutrients needed for correct growth and development.

Before transfer to the laying house, the final selection of males must be made. The selected males will be uniform with an upright posture and have grown to the correct profile. Males with leg or skeletal defects, sharp, hooked, short or uneven beaks must also be rejected as either mating will be unsuccessful or injury to the females will occur. The stage of development should be matched as closely to the females as possible using comb, wattle and feather maturity as indicators.

It is best practice to move the males to the laying house 24 hours before the females. This helps the males find feed and water more easily, critical if the growth profile is to continue on track. The males must be fed to follow the growth profile through to 30 weeks to ensure sexual and physical maturity. (See Fig. 2)

Loss of growth rate here will delay early fertility and adversely affect late fertility. By 24 weeks I would expect males to be on 135 g of feed per day, increasing by 1 g per week through to depletion. But maintaining the weight profile is paramount, feed levels will depend on nutritional values and efficacy of the separate feeding system

It is important here to remind you that male feed space should remain constant, with feeder space removed as male numbers go down. This will prevent an uneven population of males developing.

The management principles and procedures used to manage males in the post-peak period are similar to those used in the pre-peak period. Male weight and body condition are controlled by adjusting feed quantity so that a slow constant increase in weight (30g/week) is achieved as the male grows older. The revised weight profile in lay for UK Flocks is shown below. (See Table 1)

Sample males should be weighed frequently to ensure that this is achieved. Each sample male should be evaluated to determine if it is maintaining the ideal body condition in order to breed. Changes in flock feed quantities will be made based on the sample evaluated. A sample size that is too small can mislead the manager.

After 30 weeks of age, male weekly body weight gain should be approximately 30 grams when averaged over a three week period. Body weight data should be used with other husbandry information to make feed allowance decisions. The amount of feed the males can vary greatly depending on the ability of the feeding system to keep males and females from eating each others feed. With excellent control, male feed allowance is normally in the range of 130-160 grams per male/day and should be always increasing through the male's life. As a rough guide, an increase of 1g per week, from 30 weeks of age, should maintain growth and condition. Feed amounts needed depend on the security of the separate feeding systems and the energy level of the feed.

Both underfeeding and overfeeding of males are possible, and can cause problems. Underfeeding is more common after 40 weeks of age. Males require food for maintenance, growth and condition and to maintain mating activity. If nutrition is marginal, the first thing to go will be mating activity.

The males will begin to appear dull and listless, showing excess feather loss, reduced fleshing, reduced mating activity and reduced less crowing. In addition, vent colour will become paler and the variability of vent colour between males will widen. When this occurs, the more active males will work for a short period, using their body reserves, but other males will cease to function. If the condition reaches the final stages, a significant number of birds will not recover. Overall, this will result in reduced fertility.

Vent Colour

Red = Working well
Pale = Performance falling off,
less mating

On observing any of these symptoms, a number of corrective steps must be taken:

Check the male feeder is not available to females.
Check that male feed space is constant (18 cm or 7-9 males per pan)
Feed allowance should be increased 5-10 g /day).
The accuracy of weekly average weight gain data should be checked and a sample of the birds reweighed if in doubt.
Overfeeding of males will lead to males that have excessive breast development and excessive weight which can lead to damage to females, more stress on the male's joints and foot pads.

Routinely cull individual males according to their physical condition.

Males with poor feet, poor legs, poor fleshing, poor comb and vent colour should be culled as seen on a daily basis. As males are removed feed space must be adjusted to remain constant.

The technique of managing male breeders is not 'rocket science'. Attention to detail, monitoring and maintaining the correct weight gain and profile will reduce the possibilities of reduced fertility levels. Observing behaviour and reacting to it will help in maintaining a flock of quality males which will maximise fertility to the end of lay.

The profile discussed here is based on UK results and is intended for producers in the UK. Outside the UK discuss the subject with your local Aviagen Technical Manager with a view to tailoring the profile for local environmental conditions, nutritional inputs and management practices.

Source: Aviagen, Courtesy of Poultry World, October 2005

Making Every Egg Count
By Dave Watts, UK Regional Accounts Manager, Aviagen - Genetic improvement over the last few decades has seen major improvements in breeder egg production and chick output, but are you getting as much of this from the bird as you could? Two areas where output can often be gained are in better control of eggs laid on the floor and in effective management of late egg size. This article looks at management advice for these areas to maximise hatching egg output from the flock.

Controlling Floor Eggs
With improved rearing management giving better control of uniformity and body weights in rear, combined with improvements in genetics, Ross 308 breeder flocks now come into production very quickly and regularly peak at 85 - 88% by 28/29 weeks of age. These high peaks can put a great deal of pressure on the available nest box space and unless steps are taken to minimise the opportunity for birds to lay their eggs on the floor, they will start to and continue to do so through the life of the flock.

It is good practice to install perches during the rearing period to train and stimulate females in their nesting behaviour. Sufficient numbers of perches to provide 3cm/bird, or sufficient for 20% of the birds to roost, should be placed in the females’ rearing pens at around 4 to 6 weeks of age.

When the birds are transferred to the laying house, they should be placed onto the slatted, rather than onto the litter area and very soon after transfer the egg collection belts should be run at least once a day. This will allow the birds to get used to the noise. If the belts are not run before the start of production, the noise will frighten the birds from the nests and onto the litter area where they will then lay their eggs.

Auto nests require a sloping, slatted area extending to approximately 40 to 50 inches (100-125cm) from the front of the nest and which should be 16 to 18 inches (40-45cm) above litter height. Avoid putting any feeders on the slats as these will act as a barrier to birds getting to the nests as they come into lay.

Begin to open the boxes for one or two hours a day from 19 to 20 weeks of age as by this age the birds are looking for somewhere to lay. If left any later – until first egg, for example - many birds will already have been put off using the nests and the damage will have been done.

Light intensity must be a minimum of 60lux during the laying period; when increasing light intensity at the start of lay, increase that above the nest system first, as this will encourage activity around the nests. In rear and move systems, avoid excessive litter depth at first, as deep floor litter can offer a very attractive alternative to the nest.

Finally, when not in use, always seal off the front of the egg collector belt in the egg collection area, as this can act like a wind tunnel, causing drafts. Quite often birds will not use the first few boxes as they will feel cold. This is usually why floor eggs are found around the front end of the shed. A piece of wood, polystyrene or sponge is adequate to block the end, not thin, hanging plastic strips as these are ineffective.

It is important to manage the introduction of the males to the females well and to manage mating ratios during the early period of lay. Mating behaviour should be closely monitored to ensure that over mating or overly aggressive male behaviour is not forcing females to hide in corners or under feeders on the floor area to lay their eggs.

Set feeding times to avoid the peak of egg laying activity. Feeding times should be either within 30 minutes of lights on or 5 to 6 hours after lights on to prevent the majority of hens coming off the nest to feed. It is also good practice at the onset of production, to walk around the house 10 to 15 times per day, encouraging females out of corners and up into the nests. A bit of extra work when the flock is coming into lay will pay dividends later.

Management of Late Egg Size
Once the flock comes into lay and the birds have been trained and encouraged to lay their eggs in the nests, then a second opportunity to maximise hatching egg yield comes from effective management of the interaction of egg production, bodyweight and egg weight.

As the flock ages, the hens gain bodyweight while the rate of lay gets less; this is accompanied by an increase in egg size. Excessive egg size during late production will make egg handling more difficult and egg shell and albumen quality tend to be worse, at the extreme leading to poorer chick quality.

Close control of female bodyweight will help maintain good persistency of lay. Generally, a higher producing flock will produce eggs of a lower weight than one where persistency is poor. Good bodyweight control is therefore a vital part of managing egg size.

Trials have shown that if birds are allowed to become overweight, in this case 12% above target, then late egg size will be approximately 1.5g heavier than that of flocks held to the Ross target weight throughout.

Nutritional changes are sometimes made in an effort to manage egg size directly, but the benefits are usually limited. Any changes to the ration should be made with care so as to ensure there is no negative effect on egg production. Lower levels of linoleic acid, protein or specific amino acids such as methionine, after 40 to 45 weeks of age can help.

Under performing flocks are often offered increased feed levels to try to stimulate better performance. If an improvement is not achieved then the extra feed must be withdrawn immediately. In a poorly- performing flock, if peak feed levels are left too high, the pullets are likely to gain excessive bodyweight, egg production will drop further and late egg weight will increase. The situation will be made worse if feed is then withdrawn very aggressively after 35 weeks, as the heavier pullets will by then have a higher requirement for energy to support body maintenance, and in this situation, rates of lay can drop very fast.

The modern broiler breeder is continually changing, due to continuous genetic improvement and our management of the bird must therefore also change. The key to maximising hatching egg output is in responding to the needs of the bird and ensuring that they are trained in roosting and nesting behaviour from an early age. They should have free and easy access to adequate nest space and should be provided with the right nutrition at the right time to balance the needs of maintaining growth and producing eggs.

As always, the answer lies in attention to detail, especially in the early stages, if the benefits are to be maximised.

Source: Aviagen and Courtesy of Poultry World, April 2005

Golden Rules For the management of Hybro females
By Hybro B.V., Boxmeer, The Netherlands - This article by Hybro B.V. explains the golden rules for the management of Hybro females.

Check your housing and equipment!
Overstocking and competition result in stress on the birds. Avoid high stocking density, both in rearing and production (see management guide for recommendations.) Allow at least 15cm feeder space per bird, and one bell drinker per 65 birds. Make sure the feed is distributed within 4-5 minutes. Have your heating and ventilation in good order. Dark-out rearing is highly recommended: rearing houses should be completely light-tight, even at full ventilation.

Give them a good start!
Pay attention to the details: well organised housing, evenly spread litter (not too deep!), sufficient brooder temperature and adequate pre-heating, clean fresh water and feed, adequate lighting and so on.

Make the grade for 5 week body weight!
Start feed restriction early enough to ensure controlled growth from the beginning – as soon as ad lib feed exceeds 35g/day.

Make an early start on uniformity!
Start grading as early as possible, but not later than 4 weeks of age. Grade several times during rearing. Place the birds in groups and feed them to achieve highest possible uniformity at 10-11 weeks. After 12-14 weeks, focus on keeping bodyweight parallel to the standard rather than bringing them back to it.

Use grower feed with low nutrient concentration!
During rearing, use feed with an energy content of 2600-2650 kcal/kg, as it allows more feed increments, resulting in better uniformity and less stress.

Increase the feed every week!
Refer to the growth rates of the previous 2 weeks to determine weekly feed increments. These should increase smoothly and gradually, avoiding big jumps.

Don’t correct growth curve after 14-15 weeks!
If bodyweight deviates from the standard at this age, aim to keep the curve parallel to the standard. In this period, focus on an accurate weekly growth rate rather than a 20-week bodyweight target. A reduction in growth rate will result in an underdeveloped bird.

Start light stimulation according to the body weight!
Don’t start light stimulation before the average body weight of the flock is 2200g (dark-out rearing) or 2350g (daylight rearing). If uniformity is poor, delay the lighting for a further week. Make the first increase big enough (2 hours in blackout rearing, 3 hours in daylight or brown-out rearing) and increase the light intensity at the same time. Try to be on 14-15 hours of light at 5% production. Increase the day length again at 60% production, to stimulate the later maturing birds.

Keep control over the point of lay!
Avoid over-fleshing by limiting the use of a rich pre-lay feed to 2-3 weeks prior to the start of production. Decide on the use of pre-lay feed at around 20 weeks, and only use it when the bodyweight, fleshing or feathering of the birds is below standard. After 20 weeks, focus on growth rate rather than bodyweight. Avoid over-feeding before onset of lay. The objective is to be at approximately 115- 125g feed at 5% production. Be aware that the males usually steal from the female feeders up to 26-28 weeks of age.

Once production starts, gradually build up the rate of feed Increase!
Between 5% and 35% of lay, give an extra 0.5-0.7g feed for each 1% increase in production. After 35% production, give 1g feed for each 1% increase. Adjust the feed amount every 3-4 days. Don’t give peak feed before 60-65% daily production, and avoid over-feeding at peak, as it will quickly result in overweight. 165-170g of peak feed should be sufficient.

Control growth from peak of lay to end production!
Start reducing the feed quickly when peak production is reached. Reduce by 2- 3g per bird per week in the first 3 weeks, starting from the first week of peak production. Start to reduce even if the flock under-performs. Continue to reduce the ration slowly and gradually, to keep weekly growth at 10-15g. Limit feed reductions after 45-50 weeks of age.

Source: Hybro B.V. - Taken from website September 2005

The Impact of Genetics on Breeder Management
By Ron Meijerhof, senior technical specialist, Hybro B.V., Boxmeer, The Netherlands - In the world of broiler meat production, rapid developments are being made. The increase in broiler performance for all commercial breeds has been tremendous over recent years, measured not only by improvements in growth per day, but also in terms of feed conversion, carcass yield, breast meat yield, mortality and leg quality, for example.

Trends in breeder performance are not so clearly pronounced and regular, however. Today we find that modern breeders can produce peaks of up to 85 per cent, which is certainly more than we could achieve seven or eight years ago. On the other hand, it has become more difficult to obtain these maximum performances, because the birds require much stricter control without room for errors. This is particularly evident in the management of modern males. The reason for this is simple.

Important improvements
When we look at the cost price of a kg live broiler, even without processing, the cost of producing a day old chick is only about 15 per cent of the total cost price, with 85 per cent the cost of growing that day old chick into a broiler. If we calculate the cost price of a kg of meat, including the processing costs, the cost of the day old chick is less than 10 per cent of the total cost price.

This means that the cost of rearing breeders, including feeding, housing, incubation and chick processing, only adds up to 10-15 per cent of the total cost, and therefore that an improvement in breeder performance has a relatively small influence on the total cost price of the bird.

For this reason, improvements in broiler performance are typically much more important than improvements in breeder performance, which in any case are only acceptable if they have zero or negligible effect on the broiler traits. This is why in the long term most breeder companies try to keep breeder performance equal or constant to slightly positive, instead of delivering enormous improvements in breeder productivity that will consequently have a negative impact on broiler performance.

Although all breeding companies are aware of this - and effective in achieving further improvements in performance - not all companies regard the key points for improvement in the same way. Between companies and breeds, we see differences in performance, based on the importance that the individual companies give to certain aspects of broiler production.

Breeding is a long term business. It takes at least four or five years to see a change in pure lines being reflected in product performance in the field. Therefore it is vitally important to assess the direction in which markets will develop in the future accurately – and to anticipate this early enough within the breeding programme to take full advantage of market trends when they occur.

Multiple crosses
Broilers are the final product of crossing several lines. Consequently at breeder level, the genetic background of males and females can be (and almost always will be) completely different. This means that to some extent it is possible to realise broiler trends in the parent line of choice. For example, growth in a broiler can be realised by crossing a very fast growing male line with a normally growing female line, or vice versa. The selection of lines and their specific characteristics has an enormous impact on the reproduction traits, and on the management strategies that have to be applied to a certain breed.

Let’s assume that broiler growth is obtained by crossing an extreme growing, genetically heavy male with a slow growing, genetically light female. As a result, it can be expected that this breed will easily produce eggs but fertility, especially at a later age in the flock, will be more difficult to obtain. When the reverse option is used, so a heavy female with a light male, fertility will be relatively easy to achieve but getting the optimum number of eggs will be more challenging. Given these scenarios, it is clear that the management strategies and practices for these two resulting breeds will be different.

Selection goals and their influence on breeders
The breeding programme for each individual line in a breeding company is defined by breeding goals. In other words, for every line, a selection programme must be defined that describes on which selection parameters the focus must lie for that specific line. Of course breeding companies do not only select for growth, but also for other broiler traits such as yield, meat quality, feed conversion and mortality, as well as on breeder traits like egg production, shell quality and hatchability, for example. The challenge with selection is that it not only changes the parameters that the birds are selected on, but also parameters that at first sight appear to have little to do with the breeding goals.

A good, example of this is in the relationship between growth and reproduction. It is well known that a strong selection on growth has a negative influence on reproductive performance. This means that relatively more pressure has to be put on selection for reproduction if at the same time more pressure is given to selection for growth, in order to maintain constant or even slightly increased reproduction.

However, selection on yield and feed conversion also has an influence on reproduction. If high yielding, feed-efficient birds are stimulated too early and too much with feed without being able to produce the expected eggs, the birds will process that extra feed in their own body and grow excessive meat very rapidly. This meat influences the production of sexual hormones in the birds, and as a result the birds become over-stimulated. This results in poor production and high mortality, because the birds cannot handle the high stimulation of the reproductive tract.

If we take reproduction and growth as an example, we can question what causes the often discussed negative correlation between these two traits. There are two main reasons, either related to the individual hen or to the performance of the flock.

Individual birds
Egg production by an individual hen is maximal if a follicle (yolk) is produced every 24 hours, turned into a first grade quality egg and laid. This egg per day equates to 100 per cent production. When we do select on growth, it becomes more difficult for a bird to produce each follicle in good time. Often it will take the hen longer than 24 hours, and often a pause day (day without an egg) will be introduced. This is because the hormonal or developmental sequences in the bird will not be as optimal as they should be. It is not so much that the optimal sequence can no longer be achieved, but that the circumstances to get the birds into that condition are becoming much more critical. The same holds for the consistency of that bird: how long can it maintain that high level of follicle production without causing more pause days.

Flocks of birds
Of course a flock of birds is a mix of thousands of individuals, each with their own individual capacity to lay eggs, but also with their own demands on the environment to get into that optimal stage of development for producing an egg every 24 hours.

Due to selection on broiler traits, establishing the correct stage of development and the fine tuning to get to that stage is increasingly critical. The bird is becoming less forgiving in non-optimal situations, and therefore less deviation from that optimal stage is acceptable to obtain good results. As large flocks of birds will show a natural variation in development, the risk of non-optimal treatment for groups of birds increases. Every bird in the group is still able to produce, but as we manage the flock based on the average demand of all the birds, an increasing number of the birds will suffer from non-optimal conditions. Factors that increase that natural variation in development (poor rearing, high stress, poor equipment, high disease pressure etc.) will make it even more difficult to obtain good results.

Consequences for management
Selection for fast growing, high yielding broilers influences the reproductive capacity of the parent stock. To obtain good results in reproduction, we have to focus on delivering adequate management to address the needs of this specific type of bird.

Start of the flock
As individual birds accept less and less deviation from the optimal, it is crucial to have a very uniform flock at the onset of lay, to get as many birds as possible to that point simultaneously. This is more than just uniformity in bodyweight at a certain age, as it also includes uniformity in development. Achieving maximum uniformity is also about more than grading. It starts with good chick quality and start up of chick development, uniformity in frame size and the avoidance of stress and diseases, among other factors. The start up period is especially important.

High-yielding broilers (and therefore their parents) are normally selected to have a high development of organs before the real growth starts, to be able to support the rapid growth of protein later in life. This increased development in the first days normally means that the birds tend to start rather slowly and are more sensitive, especially to temperature. It is therefore very important to ensure that the house is sufficiently preheated before the birds arrive, to prevent them from becoming cold. If the birds become cold shortly after arrival, some of them will not find the feed and water for several days, and uniformity will already be adversely affected after just one week.

Quality of rearing
Even more than with classical breeds, the rearing period of high-yield breeders is crucial for obtaining maximum reproduction results. Focusing on the quality of rearing, uniformity of the flock and adequate development at the start of production pays off very rapidly. The key word in rearing is ‘gradual’. It is important to avoid changing the feed amounts too rapidly, but rather try to gradually increase the feed week by week. In the first 6-7 weeks of rearing, the weekly increase is 2 to 3 grams, then it changes to 3-4 grams until 15-16 weeks of age. In the final weeks of the rearing period, the increases will be 4 to 5 grams each week. It is very important that these weekly increases are steady and constant, to avoid any sudden changes. That sometimes means that even if the flock is a bit over- or under -weight, we should not try to correct it too quickly, but rather try to anticipate development for the coming weeks.

Start of production
A crucial period in the development of high-yielding breeders is the onset of lay. Genetically, these birds are capable of producing high amounts of (breast) meat. Managing the amount of meat growth is very important for obtaining good results. A minimum amount of fleshing is needed, to get the birds ready for egg production. However, over-stimulating with feed in this period to push the birds into egg production has a very negative impact, as the birds will grow meat very rapidly. This rapid meat growth will over-stimulate the sexual hormones and the reproductive system, resulting in poor production and high mortality. This means that the amount of fleshing must be limited by restricting feed stimulation. In this respect, high-yielding breeds in particular differ from more traditional breeds, as they are not able to handle such high feed stimulation.

The best tool for controlling this is to check the formation of the breast muscle on a regular basis. The aim is to have a U shaped breast for optimal production. If a bird is underdeveloped, the breast will feel like a V, which means that there is not a lot of meat around the keel bone. If we over-stimulate the birds either in feed quantity or in protein, we see that the breast muscle quickly develops in a W shape, which indicates over-fleshing. This over-fleshing will result in reduced production, more double yolks and increased mortality. When the birds are well developed, it is important not to over-stimulate them with a high amount of protein. To prevent this, increase the feed amount in a steady line from end of rearing to start of production, aiming at approximately 120 grams of feed at 5 per cent, regardless of the age of the flock.

Peak feed
Genetic selection for growth also influences the choice of management during the peak production phase. A strong selection on growth will mean the birds grow very fast if feed intake is not well-controlled. This means that for fast growing breeds, the amount of feed has to be reduced after peak more rapidly and aggressively, to control growth and maintain persistency and hatchability. Start feed reduction as soon after peak as possible, or the birds will gain weight on the excessive feed that is given - and then require extra feed to maintain that extra body weight.

It is good practice to reduce feed amounts one week after peak production is reached. Reduce the feed for three weeks by approximately 2 to 4 grams a week, divided into two feed reductions per week. After each feed reduction, monitor egg weight, body weight and production. While both egg weight and body weight should continue to increase, production should not decrease by more than one per cent each week. Only if that is achieved, introduce the next feed reduction.

After these three weeks of feed reduction, continue to reduce the feed by one gram per week until about 45-50 weeks. From this point onwards, it is often advisable to maintain constant feed. The aim of this whole feed reduction process is to keep increasing the bodyweight after peak at a level of about 10g per week. This is not because the birds need to grow 10 grams a week, but if the flock grows on average 10 grams, the poorest birds will at least not lose weight.

Conclusions
Changing the characteristics of birds by genetic selection has an influence on the capacity of the birds to reproduce. Not only selection on growth, but also on meat yield and feed conversion has, among others, a negative impact on reproduction. This can be partly recovered by putting more selection pressure on reproductive performance, and partly by adjusting the management programme to the specific birds. Applying classical flock management conditions to fast growing, high yielding breeds will not automatically give the highest production results. Continuous adjustment and fine-tuning of the management programme to deal with the continuous genetic changes in the birds is necessary.

Source: Hybro B.V. - May 2005

Breeder Nutrition and Chick Quality
By Marcus Kenny and Carolyne Kemp, Aviagen - This article by Aviagen discusses how the nutrition of the breeder hen affects the chicks physiology at hatching.

The developing embryo and the hatched chick are completely dependent for their growth and development on nutrients deposited in the egg. Consequently the physiological status of the chick at hatching is greatly influenced by the nutrition of the breeder hen which will influence chick size, vigour and the immune status of the chick.

Table 1. The necessary change in hatchery or broiler performance to equalise profitability when breeder feed cost is changed by 1% per tonne (for example from £UK 140.00/tonne to £UK141.40/tonne or £UK138.60/tonne).
Hatch of total eggs (%) 0.24
42 day liveweight (g) 7.4
42 day FCR 0.0015
42 day mortality (%) 0.07-0.45*
*depending on age of mortality. Calculated using input-output values for UK industry 2003 (Kemp and Kenny 2003).

The financial effects
Nutritional decisions for breeders need to take account of the overall economics of the whole production cycle. Table 1 shows the changes in hatchery and broiler performance that are required to equalise the effect of a 1% increase in breeder feed cost on the profitability of the whole production cycle. Only one of these changes is required to have the necessary economic effect; in practice all are likely to move positively making the measurements of any one change difficult.

The calculations are done under typical UK 2003 conditions and they show quite clearly that small improvements in bird performance are required to ‘pay’ for more expensive breeder feed. Conversely, apparent savings in breeder feed cost can readily lead to an overall loss if small changes in broiler performances are ignored.

Similar economic analyses have been conducted by Mississippi State University which, based on US integration 2002 costs, demonstrates that a measurable improvement in progeny liveability as a result of hen diet change can be profitable. The key point is that trying to cut the cost of a breeder feed may easily reduce the profitability of the overall enterprise.

Influence of feed allocation
Underfeeding the hen can have an impact on chick quality and this is particularly noticeable in the early production period. Modern hybrid parent flocks commence production at a faster rate than in the past and consequently egg output increases over a shorter time span during the early laying period. Feed allocations during this period have not necessarily increased in line with this egg production trend. Low feed allocation intake by young commercial breeder flocks has been shown to compromise nutrient transfer to the egg, resulting in increased late embryonic death, poorer chick viability and uniformity.

In a recent study by Leeson (2004) broiler breeders were fed different levels of feed through peak production varying from 140 to 175 grams. Although the increased feed allocation increased bodyweight there was no influence on egg size, however chick weight was influenced by feed allocation (Table 2). Of equal importance is the effect of overfeeding on ovarian development. In experimental studies ad libitum feeding has been the most widely used model for overfeeding which can result in excessive follicular development or Erratic Oviposition and Defective Egg Syndrome (EODES).

Flocks with EODES generally have poor shell quality, a reduced duration of fertility and poor hatchability. It is also known that fewer sperm will survive but it is not clear how the surviving sperm are affected and if they generate a weaker embryo. The same authors also warn that the effect of aggressive feeding two to four weeks after photostimulation reduces productive performance throughout the life of the flock.

In this period the bird switches from primarily growth to a reproductive state. The young birds’ reproductive hormone system is not mature enough to deal with high nutrient intakes; nutrients are instead metabolised to egg yolk lipid which contributes to excess follicle development.

Research shows that nutrient supply to the broiler breeder is of consequence to chick quality and production performance. This places greater emphasis on the nutritionist providing the correct nutrient density diet and the flock manager to provide appropriate feed intake to the bird coming into lay.

Table 2. The effects of breeder feed levels on chick weight.
Peak breeder feed (g/b/d) 30 week breeder chick weight (g)
140 40.3
147 40.0
155 41.5
162 41.7
169 41.8
175 42.0

Diluted breeder diets
The use of diluted breeder diets is receiving a lot of attention in Western Europe on the basis of improvements in bird welfare. Experimental work feeding low energy density diets to young parent stock gave a delayed onset of oviduct development, increased early egg size, faster development of the embryo and a higher live weight of day old chicks. When broiler mortality was above average, low density broiler breeder feeds gave a significant reduction in mortality of offspring. Other experimental work showed improvements in breeder productive performance when diluted diets were fed in the rearing period.

Vitamins
Vitamins are involved in most metabolic processes and are an integral part of foetal development, therefore the consequence of suboptimal levels of these nutrients in commercial diets are known to result in negative responses to both parent and offspring performance. Vitamins account for about 4% of the cost of a breeder feed, so economising on vitamin inclusion rates is rarely an option

Table 3. Some practical recommendations for vitamin
supplementation of breeder feeds (Fisher and Kemp 2001).
Vitamin Leeson & Summers (1997) DSM Ross
A (iu/g) 7 10-14 13
D3 (iu/g) 3 2.5-3.0 3
E (mg/kg) 25 40-80 100
K (mg/kg) 3 2-4 5
Thiamine (mg/kg) 2.2 2-3 3
Riboflavin (mg/kg) 10 8-12 12
Pyridoxine (mg/kg) 2.5 4-6 6
B12 (mg/kg) 0.013 0.02-0.04 0.03
Nicotinic acid (mg/kg) 40 30-60 50
D-pantothenic acid (mg/kg) 14 12-15 12
Biotin (mg/kg) 0.2 0.2-0.4 0.3
Folic acid (mg/kg) 1 1.5-2.5 2

The levels of vitamin supplementation recommended by different sources have been summarised in Table 3. Generally there is a shortage of information on vitamin requirements of broiler breeders especially when related to offspring performance. Most of the breeder work is quite dated and since that time breeder performance has changed. It would be impossible to review all the literature in this article, however a review of work on fat soluble vitamins, biotin and pantothenic acid have shown that vitamin E has the largest impact on progeny.

Table 4. Impact of dietary breeder vitamin status on bodyweight, enzyme activities, tissue characteristics and immunity of progeny.
Vitamin Progeny response
Vitamin A Increased liver vitamin A in embryonic and chick liver but decreased vitamin E, carotenoids and ascorbic acid. Surai et al. (1998).
Carotenoids No positive impact on chick growth, organ development or humoral immunity in chicks five weeks post hatching. Haq et al. (1995).
Carotenoids Transferred from the hen to the yolk but not absorbed well by the embryo and subsequent chick. Haq and Bailey (1996).
Carotenoids and Vitamin E Carotene, vitamin E, and their combination improved and vitamin E lymphocyte proliferation, but only vitamin E improved humoral immunity. Haq et al. (1996).
Vitamin E Vitamin E levels of 150 and 450mg/kg increased passively transferred antibody levels in chicks to Brucella abortus up to seven days of age. Jackson et al. (1978).
Vitamin E Increased vitamin E in chicks’ yolk sac membrane, liver, brain and lung all of which had reduced susceptibility to peroxidation. Surai et al. (1999).
Vitamin E Increased progeny antibody titers to sheep red blood cells at hatch. Boa-Amponsem et al. (2001).
Vitamin E and Selenium Increased liver glutathione activity in chicks. Increasing selenium increased selenium dependant glutathione peroxidase in chick liver. Surai (2000).
Vitamin D Tibial calcium was increased at two weeks post hatching and tibial ash increased at four weeks of age by increased vitamin D3. Ameenudin et al. (1986).
Vitamin K Chicks from hens fed vitamin K deficient diet had reduced tibial glutamic acid levels at day one and 28 post hatching but tibial glutamic acid was restored by supplementing the chick diet with vitamin K. Lavelle et al. (1994).
Biotin Foot pad dermatitis and incidence of breast blisters were decreased in some trials in chicks from hens fed biotin fortified diet. Harms et al. (1976).
Biotin As biotin increased in the hens’ diet, yolk and chick plasma also increased. Biotin concentration in chick plasma was poorest from young hens. Whitehead (1984).
Pantothenic acid Liveability of chicks was best when hens were fed 20mg/kg diet of pantothenic acid. Utno and Klieste (1971).
Adapted from M. Kidd 2002

The production and economic effects of vitamin E supplementation are best shown by Hossain et al (1998) where a basal corn soya feed was supplemented with 25, 50, 75 and 100mg/kg vitamin E. The effects on hatchability were not significant; however the best hatchability was obtained at 50mg/kg at 52 weeks. Offspring immune response continued to increase up to 100mg/kg. In the same studies higher final bodyweights at 42 days, improved FCR and reduced mortality were observed in chicks from eggs which had been injected with vitamin E in ovo.

Haq et al., (1996) working with very high levels of vitamin E (134mg/kg versus 412mg/kg) found no growth response to 21 days and an improvement in FCR for the offspring of hens receiving the supplemental feed. In other studies the combination of selenium and vitamin E to broiler breeders has been shown to increase liver glutathione activity of progeny. In general it seems to be justified to supplement practical breeder feeds with 100mg/kg vitamin E.

There appear to be mixed reports on the efficacy of vitamin C; some experiments suggest a positive response, but a more recent study failed to detect any benefit on any production parameter. This lengthy study used corn soya diets supplemented with 75mg/kg stabilised vitamin C which when analysed recovered 49mg/kg which might explain the variability of response.

The influence of increased vitamin levels fed to young parent stock on progeny performance is an area which has received significant commercial interest. Work conducted at Aviagen Ltd has shown chicks derived from 31 week old parent stock fed elevated levels of vitamins showed improved growth to 11 days and reduced mortality compared to chicks derived from 42 and 45 week old parents. Similar responses have been found in the field where chicks derived from young parents fed increased levels of vitamins have benefited in terms of viability and liveability. Perhaps this supports the need for further work exploring the vitamin requirements of the breeder in the early production period.

Whitehead (1991) proposes that a basis for making recommendations is to feed vitamin levels that maximise the resulting level in the egg. For vitamins with active transport mechanisms (thiamine, riboflavin, biotin, cobalamin, retinol and cholecalciferol) these levels reflect the saturation of binding proteins.

Levels derived in this way include 10mg/kg for riboflavin and 250 microgram/ kg for biotin. Whitehead (1991) contrasts this level of riboflavin with the conventional requirement (4mg/kg in this case) but the higher figure – the upper limit to nutritionally useful range – may be a better guide to good commercial practice.

Table 5. Blood cell count of the broiler derived from parents fed high or low vitamin and mineral levels (Rebel et al 2004).
Breeder low vitamins/minerals Breeder high vitamins/minerals
Heterophil 5.3 3.8
Lymphocyte 4.6a 21.4b
Monocyte 1.1 5.3
Basophil 0.0a 5.4b

Table 6. Summary of minerals fed to breeders shown to have an effect on progeny performance.
Growth Liveability Immune function Skeletal
Fluoride X
Phosphorus X
Selenium X
Selenomethionine X X
Zinc X X X
Zinc and methionine X
Adapted from M. Kidd 2002

Vitamins and chick immunity
Reference has already been made to the effect of vitamin E on chick health and immune function, while other vitamins have been researched none show the same degree of effect as vitamin E. Table 4 summarises work investigating the effect of different vitamins fed to breeders and consequent impact on progeny health. Recent work by Rebel et al (2004) investigated the effects of several elevated levels of vitamins and trace elements fed to breeders and broilers on the immune system of birds infected with malabsorption syndrome.

Broilers derived from breeders fed elevated vitamins and mineral levels had increased numbers of leukocytes at day old which indicated stimulation of the immune system (see Table 5).

Fig. 1. The effect of protein-to-energy ratio in the breeder feed on chick weight at hatch (Spratt and Leeson 1987).

Major minerals
Calcium, phosphorus, sodium, potassium, magnesium and chloride are involved in shell formation hence general improvements in shell quality lead to better egg and chick quality. Variations in maternal phosphorus supply have been shown to influence bone ash of young but not older progeny. Broiler performance was not affected by these treatments so the practical significance of this work is not clear but the use of relatively low phosphorus levels in breeder diets, while benefiting egg shell quality, may not lead to the best possible bone integrity in the early stages of growth.

Trace minerals
Most interest in this field has centred on the use of chelated minerals which have been shown to increase deposition in the egg and transfer to the tissues of the hen and the embryo. Most recent work has focused on the antioxidant status of breeders, embryos, offspring and the role of selenium. Surai (2000) has shown the role of Selenomethionine on both vitamin E and glutathione peroxidase levels in eggs, embryos and chicks up to 10 days of age.

The economic benefits of using Selenomethionine compared with sodium selenite have been examined in a number of unpublished field trials in the UK. Hatchability improvements ranged between 0.5-2.0 chicks per 100 eggs and in another trial 0.3-0.7 chicks per 100 fertile eggs. Few of these tests involve a proper assessment of subsequent broiler performance although comments about chick quality are generally positive.

In one of the commercial trials mentioned an improvement of 0.5% in mortality and cull rate at 10 days was observed when organic selenium replaced sodium selenite. Research has indicated that the improvements in chick immunity as a result of mineral fortification of hen diets may result in improved liveability. Flinchum et al. (1989) demonstrated that leghorn breeders fed supplemental zinc methionine to a zinc adequate diet had progeny with improved survival to an E. coli challenge. Similar improvements to progeny liveability were seen with breeders fed supplemental zinc and manganese amino acid complexes. Table 6 is a summary of those minerals which, when fed to breeders, have an effect on progeny performance.

Nutrient levels in the breeder diet
There is clear evidence that a high protein to energy ratio depresses hatchability, and probably chick performance. The experiment by Whitehead et al. (1985) shows the effect of excess protein where the higher protein level reduced reproductive performance, producing 3.1 fewer chicks per 100 fertile eggs.

Chick quality was also reduced so that the difference in saleable chicks was 4.0 per 100 fertile eggs. The effect of energy protein ratio in the breeder feed is shown in Fig. 1. This emphasises both the effects of excess and inadequate protein, and also indicates that the optimum level is quite steeply defined.

According to this trial the optimum protein level is at 5.52g protein per 100kcal which converts to an optimum of 15.18% protein for a diet containing 2,750cal/kg of feed. The protein level of the diet and its ratio to energy is important not only for parent performance but also for chick quality.

Table 7. Commercial comparison of breeder feeds based on wheat or maize (400g/kg).
Advantage of maize over wheat based feed
Mortality during lay (%) -1.7
Total eggs (per hen housed) +3.8
Hatching eggs (per hen housed) +4.8
Hatching/total eggs (%) +0.9
Hatch of set eggs (%) +0.6
Hatch of fertile eggs (%) +1.1
Second quality chicks -0.1
Based on a comparison of two commercial houses each containing 6500 female grandparent breeders. Data to 58 weeks (Ross Breeders, unpublished data, 1998).

The effect of feed ingredients
There is evidence of improved breeder performance when maize is compared to wheat as the main cereal in breeder feeds. From a survey of many depleted commercial flocks overall hatch of fertile eggs in the UK based on wheat diets and Brazil based on maize diets is 83.3 and 86.2 per 100 eggs respectively. Other management factors may contribute to this difference in hatchability other than cereal source; male management is very good in Brazil and the resulting high fertility may also contribute something to this difference. Unpublished commercial development trials from the Netherlands and Aviagen Ltd grandparent flocks (see Table 7) support this observation.

The most likely benefit of maize is probably in shell quality and thickness. From the same data average poorer shells with specific gravity of <1.08 accounted for 26.1% of eggs from wheat fed hens and 17.1% from maize fed. Studies of hatching losses showed less late dead embryos (>18 days) and less bacterial contamination. These two responses are expected with eggs of better shell quality. Evidence about fat levels and sources is conflicting but there is no question that this is an important consideration. Added fat levels should be kept low in breeder feed (1-3%) and preference given to unsaturated vegetable oils rather than saturated animal fats. Work from Mississippi State University compared maize oil and poultry fat and generally supported the use of more unsaturated fat (see Table 8).

Maize oil increased 21 day bodyweight over that of poultry fat and improved slaughter weight of broilers in comparison to equal levels of poultry fat and lard.

Table 8. Experiments comparing fat sources and/or levels for broiler breeders.
Reference Fats compared
Brake (1990) PF
Brake et al. (1989) PF
Denbow & Hulet (1995) SBO, PF, FO
Peebles et al. (1999a, b) CO, PF, LA
Peebles et al. (2000a) PF, CO, LA
Peebles et al. (2000b) PF, CO, LA
Fats: PF – poultry fat; SBO – soybean oil; FO – fish oil; CO – corn oil; LA – lard

Summary
Over and undersupply of nutrients into and through lay can have a very significant impact on breeder production and quality of progeny. This places greater emphasis on the nutritionist providing the correct nutrient density diet and the flock manager to provide appropriate feed allocation in lay.

Addition of micronutrients to the breeder has been shown to be beneficial to progeny quality especially in the early production period. Use of specific dietary ingredients such as maize can affect breeder performance and progeny quality. Both on economic grounds and on biological grounds, high quality nutrition of breeders is well justified.

Source: Aviagen - June 2007

A Health Program for Small and Specialty Poultry Flocks
By The University of Maryland - This article looks at setting up and managing small flocks.

Practice Confinement Management. Always keep your poultry housed or in a fenced area. Never let poultry or other fowl run loose. Try to eliminate all contact between domestic poultry and free-flying waterfowl or other wild birds. Dead birds should be burned or buried at least one foot deep or properly composted.*

Avoid Mixing Types. Keep wild or tame waterfowl, cage or pet birds, ratites, and any other exotic birds on separate premises from chickens, turkeys and game birds. If this is not possible, maintain in separated, nonconnecting pens. It is important to raise all species separately, if possible, to minimize the spread of disease.

Wild waterfowl are reservoirs of avian influenza and other diseases; mixed-species poultry operations can serve as a catalyst for virus mutation and increase the risk for disease outbreaks. Just as chickens and turkeys should not be kept together, so should web-footed birds (ducks, geese and other waterfowl) be kept away from non-web-footed birds such as chickens, turkeys, game birds, etc.

Control Human Traffic. Lock doors. Allow visitors only after they have put on properly sanitized footwear, clothing and hats. Change clothes and footwear before leaving home and upon returning to your premises. Do not transfer fecal material and dust to or from your flock.

No Unsanitary Crates, Equipment or Vehicles. Insist that all buyers of poultry bring only clean, disinfected crates, equipment and vehicles onto your farm, with no visible fecal material or feathers.

Better yet, take your birds to a predetermined location. Clean your hauling equipment before returning home. Remember, one speck of fecal material or a feather can carry billions of infectious germs.

All In, All Out. Process the entire flock at least every 12 to 15 months when possible. Freeze the meat for later consumption.

Wash and disinfect the poultry house. Then leave it empty for two weeks. Replace flock with healthy chicks from a single source. Do not add any new stock until the next cleanup. Limit the number of different age groups on your farm.

When all-in, all-out is not possible, bring new stock onto your farm only by hatching fertile eggs that you have purchased, or by buying Pullorum-Typhoid Clean chicks. Adult birds can be disease carriers, even if they appear healthy.

Nutrition. Fresh, clean feed and water should be available at all times. Keep feeders and waterers clean. Use feeds that are balanced for the species being raised. For example, do not feed turkey feed to laying hens, chicken feed to game birds, or cattle feed to poultry.

Generally, day-old to 21-day-old birds, and birds under stress-- such as from moving and severe weather changes-- can benefit from vitamins and electrolytes added to their drinking water.

Health Specifications. Insist that (1) replacement chicks have been vaccinated against Marek’s disease; (2) all chickens, turkeys, game fowl or waterfowl purchased are officially classified as U.S. Pullorum-Typhoid Clean. Participate in avian influenza testing programs where available.

Medication. Feeds used for day-old to eight-week-old turkeys and day-old to 16-week-old floor- or range-reared chickens should include a coccidiostat. After turkeys are eight weeks old, a blackhead preventative should be added to their feed. Nitarsone with bacitracin at low levels is the only medication cleared for prevention of blackhead.

According to law, a number of medications, including anticoccidial drugs, have a withdrawal time before meat or eggs can be consumed. Read and follow all label directions. For additional help, consult with your local veterinarian, county Extension educator or feed dealer.

* Burial and incineration subject to local environmental regulations. Check with your state Department of Agriculture representative.

Source: University of Maryland College of Agriculture and Natural Resources - August 2004

Managing Today’s Broiler Breeder Female
By G.T. Tabler and R.K. Bramwell, University of Arkansas - Managing the modern broiler breeder female so that she will produce a large number of high quality hatching eggs is a delicate combination of both art and science. This article delves deeper.

More on the Authors
G.T. Tabler
Applied Broiler Research Manager
R.K. Bramwell
Extension Reproductive Physiologist
Introduction
Over the past few decades, broiler breeders have undergone intensive selection for faster growth rate, increased yield and improved feed conversion.

Although these traits are measured at the broiler level, they impact the breeder hen in ways we often do not consider. The objective with broiler breeders is to have them consume an “ideal” amount of nutrients within a given time period to produce a bird whose weight, body condition and frame allow the reproductive organs to mature and function at their best. How do we combine art and science to manage the sexual maturation of today’s broiler breeder female?

Photostimulation
One of the most critical time periods in broiler breeder hen management is the time from photostimulation (lighting) to peak production (Robinson, 1995). This period is characterized by relatively fast weight gains, in addition to changes brought about by the development of a functioning, hormone-producing ovary. Lighting the breeder pullet flock is generally considered the cue to initiate puberty, although the response to lighting can be modified by the feeding program.

At photostimulation, light energy passes through the skull of the breeder pullet into the brain and “illuminates” the hypothalamus. The hypothalamus in the brain is much like the main circuit breaker in a house; it controls a variety of body processes including reproduction. The brain acts in concert with the liver, skeletal system, ovary and oviduct to make up the reproductive system in the breeder hen. After the hypothalamus receives a photostimulatory signal (long day length above a certain threshold of intensity), the hypothalamus secretes specific hormones that travel to the anterior pituitary portion of the brain (Robinson, 1999). The anterior pituitary produces hormones known as Luteinizing hormone and Follicle Stimulating hormone that travel to specific tissues in the ovary to stimulate ovarian function.

One of the first responses seen when looking at the ovary of the pullet after lighting, is that the tiny ovarian follicles begin to increase in size. These small follicles produce large quantities of estrogens. Estrogen causes most of the reproductive transformation associated with puberty.

Firstly, estrogen increases the production of yolk precursors in the liver of the bird. Visibly, the liver can be seen to enlarge and become paler as it increases in fat content for production of egg yolk lipids. Secondly, the oviduct increases in size, as it must be ready to receive ovulated follicles by the time the ovary has mature follicles ready to ovulate. Thirdly, estrogen results in changes to bone composition, so that calcium can be mobilized daily to facilitate egg shell formation. Finally, estrogen, together with male sex hormones, results in changes to plumage, comb size and sexual receptivity to males (Robinson, 1995). Traditionally, flocks receive photo stimulation when they are 20-22 weeks of age resulting in onset of egg production at approximately 24-25 weeks of age. This program tends to maximize egg numbers, but may result in eggs that are smaller than standard early in the laying cycle. It also often results in egg production before hens are capable of producing a quality germ cell. Lighting birds later than 20-22 weeks allows females to become larger and more mature at the onset of production. Unfortunately, lighting birds later will likely also delay egg production until 25-26 weeks. However, this may or may not affect the total number of hatching eggs produced.

Ovulatory Cycle
Yolk is deposited into follicles as they proceed through the hierarchy to become mature. Two requirements must be met for the follicle to ovulate. First, the follicle must send a hormonal signal to the hypothalamus through the release of progesterone that signals that it is mature. Second, the hypothalamus must receive the signal from the mature follicle during a 6 to 8 hour period of the day in which the hypothalamus is responsive to the progesterone signal (Robinson, 1999). Follicular maturation typically takes longer than 24 hours, which means, consequently, that the ovulatory cycle is set back slightly each day as eggs are laid progressively later in each day similar to the sequence shown in Table 1. Hens that have slow rates of follicular maturation (26-28 hours or more) lay short (2-3 day) sequences. On the other hand, hens that lay very long sequences typically have maturation rates of 24 hours, or perhaps less. Sequence length changes throughout the egg production year with the longest sequences seen at the time of peak production at about 30-35 weeks of age. All hens lay one characteristically long sequence of eggs known as the “prime sequence” which in broiler breeders is usually about 20 eggs in length (Robinson, 1999).

Feed Requirements
While feeding programs differ across the country due to differences in integrators, complexes, weather conditions, seasons and genetic strains of birds, it is important to be continually adjusting the feeding program to provide the nutrients needed for optimum performance. Breeders require these nutrients for body maintenance, growth and egg production.

Body maintenance requirements, which include maintaining body temperature and systems within the bird that allow for digestion, respiration, excretion and immune response, range from 50 to 75% of a hen’s daily needs. As with most animals, body maintenance needs have priority, since the breeder hen must maintain her own body to survive. While the growth needs of hens during the post-peak production period do not contribute greatly to the hen’s daily nutrient requirements, pre-peak growth can be substantial. Nutrient needs for reproduction are a function of the number and size of eggs produced. In general, egg production exerts more influence on nutrient requirements than does egg size. This is part of the reason a service technician always has his/her calculator in hand and adjusts the feed allocation on each visit to the farm. This is an attempt to maximize egg numbers and keep hen body weight on target, since overwieght hens produce fewer eggs than trimmer hens.

Table 1. Times of oviposition for individual hens laying 2- to 7-egg sequences¹.
Sequence Length Time of Oviposition
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7
2 eggs 09:28 AM 01:30 PM
3 eggs 08:08 AM 11:26 AM 02:40 PM
4 eggs 08:20 AM 09:45 AM 01:45 PM 03:37 PM
5 eggs 07:56 AM 09:03 AM 10:45 AM 01:11 PM 03:05 PM
6 eggs 07:20 AM 07:59 AM 09:04 AM 10:11 AM 12:56 PM 03:40 PM
7 eggs 07:47 AM 08:15 AM 09:20 AM 09:40 AM 11:36 AM 01:09 PM 03:24 PM
¹ Adapted from Robinson, 1999.

Flock Uniformity
Flock uniformity is critical to proper feed allotments. If there is a great deal of variability in body weight, and all birds have equal opportunity to eat, the small birds will over-consume and larger birds will under-consume in relation to their nutrient requirements (Robinson, 1999). Uniformity issues are most critical at the time of photo stimulation and will usually result in poor peak performance as well as significant problems in post peak periods. In non-uniform flocks, birds receive the same feed allotment, but feeds are formulated for birds in lay. Since birds in lay have higher nutrient requirements than non-laying birds, nonlaying birds will over consume relative to their requirements and get fat, which will hinder future performance. Clearly, uniformity is necessary to obtain peak performance in breeder females.

Summary
Properly managing the sexual maturation of the modern broiler breeder female is critical to obtaining a high peak and large overall number of quality hatching eggs. The most critical management period for broiler breeders is from photo stimulation (lighting) to peak production. Management deficiencies during this period are always costly and often cannot be compensated for at a later date. Broiler breeders require nutrients for maintenance, growth and egg production. Maintenance needs are met first and until that happens, growth and egg production are reduced. Adjusting the feed allotment throughout the lay cycle controls bird nutrient intake. Intake must be strictly controlled to prevent hens from becoming overweight resulting in decreased egg production. Flocks must be uniform in weight and body condition in order to properly allocate feed allotments. Uniformity is especially critical at the time of lighting. Flocks that vary excessively in uniformity are nearly impossible to properly manage from a feed allotment standpoint. This will have a negative impact on performance and may lead to a low, flat peak and decreased overall production. Remember that the key to managing the modern broiler breeder female is a combination of 1) correct body weight and uniformity, 2) light stimulation, and 3) feed stimulation. A sound, consistent management program must be in place that will address each of these areas in order to be successful.

References
Robinson, F.E. 1995. Broiler breeder research update: Limiting ovarian development to maximize chick production in broiler breeders. University of Alberta, Edmonton, Alberta, Canada. Available at: {Accessed 11/26/02}.
Robinson, F.E. 1999. Management for control of ovarian development in broiler breeders. Ross Technical Bulletin. April 1999. Ross Breeders, Inc.

Turkey Coronavirus and Astrovirus in Britain
A study into the prevalence of turkey coronavirus and astrovirus in Britain found that the disease was most common in young birds aged between three and 18 weeks, writes Chris Harris, Senior Editor for ThePoultrySite.

Turkey coronavirus, an acute and highly contagious enteric disease that results in economic losses on turkey farms was seen initially in the USA in the 1990's. Studies in the US showed that the condition led to poor fed conversion, poor weight gain and an increase in the use of medication.

The studies in the US also showed that the condition caused poultry enteritis mortality syndrome (PEMS) in the young birds with the most deaths spiking at about 19 days of age.

Speaking at the British Poultry Council Turkey Research Conference, Dr Francesca Day, who now works with the Department of the Environment Food and Rural Affairs, said that the economic consequences for the outbreaks in the US were that mortality could be very high, dependent on factors such as the viral load or the presence of bacteria. Turkey coronavirus (TCoV) brought the survival in the flocks down from 93 per cent to 86 per cent.

Dr Day said that it had been proved in the US that Turkey coronavirus and astrovirus, which is an immunosuppressive, was often associated with other disease and a UK study was established to discover the prevalence in Britain and the effects the conditions were having on turkey flocks.

The disease, TCoV was first confirmed in Britain in 2001. The incidence found it in 13 day old poults with 20 per cent showing symptoms of stunting, unevenness and lameness and a mortality rate of four per cent.

The UK experiment looked at the frequency of TCoV and TAstV in flocks across England and Wales. It looked to find out whether the conditions were associated with other disease, a what age the birds were infected and what percentage of one-off scouring cases are associated with the condition. The study also looked at how many genotypes of TCoV and TAstV are circulating in Britain.

The studies took samples on a weekly basis from poults aged from one day to 20 days at a specific site and random samples were also taken from birds at any age when they showed signs of scouring. Sera was also taken from 10 birds at one day, 10 weeks and 20 weeks.

"Between 300 and 500 samples were taken and processed through extracts from the faeces," Dr Day said. "We took all the steps to avoid cross contamination in the labs."

The lab tests were able to detect the amount of infectious virus in each sample.

In the tests on the randomly selected birds that were scouring, 11 of the 34 flocks tested were TCoV positive. In the longitudinal tests where the birds were tested from one to 20 days, 24 out of 145 samples - six out of 17 flocks - were TCoV positive.

Positive samples of TCoV were from birds aged between three and 18 weeks old and for TAstV from birds one week to 12 weeks old.

All the positive samples were from birds aged between three and 18 weeks old and 76 per cent of the positive samples came from birds aged over six weeks. However, the tests also revealed that TCoV was not only found in scouring flocks - 22 per cent of the longitudinal tests were found to have TCoV, while 33 per cent of the one off samples from the scouring flocks had the condition. The tests also showed that 13 out of 36 flocks (36 per cent) that were scouring were positive for TAstV, while 10 out of the general studied 17 flocks (59 per cent) tested positive for TAstV. All these positive samples were from birds aged between one week and 12 weeks. Dr Day said that while TAstV had not been discovered only in diseased flocks, the study found that usually they were unwell when they contracted the condition.

From the sera tests, 59 flocks were analysed and a 49 per cent prevalence of TCoV was found.

Dr Day said that in the US the preventative measures that were taken included removal of any dead birds and good management of the litter as well as controlling contact with vermin and wild birds. Prevention was also aided by monitoring for the conditions and switching from multi-age to single age sites.

Note
The survey was a PhD study conducted by Dr Francesca Day and Dr Dave Cavanagh and Dr Paul Britton at the Institute of Animal Health and sponsored by Merial.
March 2008

Health Issues Facing the US Turkey Industry
Published in Poultry Health Report, August/Winter 2007, a National Institute for Animal Agriculture Publication. The lack of approved efficacious drugs continues to be a top challenge facing the U.S. turkey industry.

That was a key point delivered by Dr. Charles Corsiglia, Foster Farms, Fresno, Calif., when he spoke at the annual meeting of the United States Animal Health Association (USAHA) in October.

Dr. Corsiglia’s presentation centered on information gleaned from a poll of turkey industry veterinarians regarding the health status and issues facing the industry between August 2006 and August 2007. The poll was conducted by Dr. Steven Corsiglia, Alpharma Animal Health, West Jefferson, N.C.; Dr. Mark Blakley, Carroll’s Turkeys, Warsaw, N.C.; and Dr. Dave Mills, Jennie-O Turkey Store Company, Willmar, Minn.

“The survey shows that the turkey industry supports the scientific examination of the evidence in the cases against the use of antibiotics in agriculture, and supports the continued judicious use of antibiotics in animal agriculture,” Dr. Corsiglia stated.

That said, the turkey veterinarians participating in the poll listed the lack of approved, efficacious drugs as their No. 1 issue facing the industy.

“For example, the withdrawal of the new application for drug approval (NADA) for enrofloxacin use in poultry in 2005 leaves the industry with only tetracycline and penicillin as available therapeutics, and neither of these are adequate against colibacillosis or fowl cholera, the second-rated and ninth-rated disease concerns, respectively, in the poll,” Dr. Corsiglia explained.

Survey participants ranked blackhead, also known as histomoniasis, No. 22. This disease, Dr. Corsiglia noted, has no efficacious drug approved for use in turkeys. A total of 68 reported cases of blackhead were reported between August 2006 and August 2007. Losses to blackhead have been severe and can be devastating in affected individual flocks. Sporadic cases are occurring in North America.

“Dimetridazole was extremely efficacious and previously approved for use in turkeys for the prevention and treatment of blackhead, but it was banned in 1987,” Dr. Corsiglia told the group. “The lack of any legal treatment for histomoniasis is of concern, especially in the case of valuable turkey breeder candidate flocks. It seems unconscionable that the industry is unable to prevent the suffering and death in flocks affected by histomoniasis when effective, yet unapproved, treatments exist.”

Dr. Corsiglia said the authors of the report urge the FDA consider allowing limited use of such products in valuable breeder stock.

The poll ranked late mortality as No. 3 and leg problems as No. 4 among the turkey industry’s top concerns. Late mortality is defined as mortality in excess of 1.5 percent per week in toms 17 weeks and older. Mortality was not diagnosed to a specific disease or cause.

Excess cumulative mortality of 5 to 10 percent in toms prior to slaughter has been reported. Dr. Corsiglia said late mortality may be associated with physiologic or biomechanical deficiencies following early rapid growth in heavy toms achieving genetic potential, aggressive behavior noted in mature toms, cannibalism, leg problems and/or hypertension.

The survey revealed that leg problems, such as spiral fractures of the tibia or femur, are a common complaint.

Although the survey average decreased from 3.5 to 3.1 and moved from No. 3 to No. 5, survey results show that cellulitis remains a major disease issue across all geographic regions. Dr. Corsiglia shared that cellulitis is most commonly seen in, but not limited to, commercial male turkeys nearing market age, and the prevalence and severity of cellulitis continues to increase.

According to the poll, veterinarians indicate that the occurrence of cellulitis is now confirmed at younger ages and in both toms and hens.

Individuals participating in the poll ranked heat stress at No. 6 and poultry enteritis of unknown etiologies at No. 7.

Dr. Corsiglia shared that highly pathogenic Avian Influenza (H5N1) continues to infect poultry in Southeast Asia with sporadic introductions in Europe and Africa. He said that poultry in the U.S. have continued to remain negative for H5N1. The concern does exist, however, that the virus could spread to the U.S. through the illegal transport of infected birds or migration of infected wild birds.

The National Poultry Improvement Plan (NPIP) Commercial Poultry H5/H7 LPAI surveillance program, Dr. Corsiglia noted, provides for 100 percent indemnity for commercial plan participants. In many geographic areas where flock isolation is practical, he said controlled marketing may be the preferred method of eradication since consumption of meat from LPAI flocks does not pose a risk to the public health. If flock destruction is necessary in the eradication of H5/H7 LPAI, then 100 percent indemnity is appropriate, as it is already provided for in the eradication of HPAI.

Dr. Corsiglia called federal regulations governing the use of autogenous veterinary biologicals “antiquated” and inhibitory toward effective preventive applications in the poultry industry. He said main issues include the narrow time limits on the use of a microbiological isolate and the restrictions requiring use only in the herd of origin. As such, the turkey industry urges the Veterinary Services-Center for Veterinary Biologics to revise these regulations in favor of a more effective and user-friendly approach.

The Top 10 Disease Issues in Turkey health survey (September 2007) according to U.S. veterinarians:

Issue Score Average (1-5)
Lack of approved, efficacious drugs 4.7
Colibacillosis 3.4
Late Mortality 3.4
Leg Problems 3.3
Cellulitis 3.1
Heat stress 3.1
Poult Enteritis of unknown etiologies 3.0
Bordetella avium 2.7
Cholera 2.7
Breast Blisters and Breast Buttons 2.7

February 2008

Factors Influencing Shell Quality
This is a three-part series of articles analysing egg shell quality. It was written by Dr Lokesh Gupta, Regional Technical Manager, Avitech

NEW BOOK
A comprehensive practical guide to improving egg quality.
BUY NOW Part 1: Maintaining Egg Shell Quality
Part 2: Factors Influencing Shell Quality
Part 3: How to Improve Shell Quality

Numerous factors affect the functional quality of the egg shell mostly prior to the egg is laid. The thickness of the shell is determined by the amount of time it spends in the shell gland (uterus) and the rate of calcium deposition during shell formation. If the egg spends a short period in the shell gland, the thickness will be less. Also, the time of the day when the egg is laid determines the thickness of the shell. In general, the earlier in the day or light portion of the photoperiod, the thicker the shell will be.

Strain: Some strains of the birds may be able to deposit calcium for the egg shell at a faster rate than others, resulting in better deposition. It is observed that darker brown eggs have a higher shell quality than lighter brown eggs.

Diseases: Diseases like infectious bronchitis (IB), Newcastle disease (ND), avian influenza (AI) and egg drop syndrome (EDS) affect the shell quality. IB virus causes soft/rough shelled eggs, discolouration and wrinkling of the shell. EDS virus affects only the shell gland but with ND or IB, every portion of the reproductive tract can be affected.

Management: Poor housing, high ambient temperature, rough handling of the eggs will affect the eggshell quality. Since large eggs are more prone to cracks, the egg size must be managed through proper nutritional and lighting management. Management: Poor housing, high ambient temperature, rough handling of the eggs will affect the eggshell quality. Since large eggs are more prone to cracks, the egg size must be managed through proper nutritional and lighting management.

Eggs from hens in the 3L:1D (3 days light : 1 day dark) regimen had a significantly greater shell breaking strength than eggs from hens in the 16L: 8D (16 hours light : 8 hours dark) regimen.

Moulting: The management practice of "forced" or "induced" moulting has shown to improve shell quality in all ageing flock. Following the moult, egg specific gravity, shell weight, shell thickness and percentage shell were either the same as they had been prior to the moult, or had improved, for all strains. Egg shell breaking strength improved in all strains as the result of the induced moulting.

Age of Bird: As the hen ages, the thickness of the shell usually declines. Older flocks lay larger eggs, which break easily. The hen is genetically capable of placing only a finite amount of calcium in the shell. Secondly, hen looses some of her ability to mobilize calcium from the bone, and is less able to produce the needed calcium carbonate. The absorption and mobilization of calcium decreases to less than 50% of normal after 40 weeks of age.

Drugs: For example, sulfa drugs affect the eggshell quality whereas tetracyclines have some beneficial effects.

Water Quality: Many studies showed that saline drinking water, including tap water containing sodium chloride supplied to mature laying hens at concentrations similar to those found in underground bore water, has an adverse effect on eggshell quality while having little effect on feed intake, egg production or egg weight. In contrast some reports indicate that there were no visible shell defects and specific gravity was also not adversely affected.

Stress: While a genetic predisposition for egg and eggshell quality exists, good genes can be upset by environmental stresses. The shell is formed by the activity of cells lying the oviduct and uterus. Under stress the secretions of these cells become acidic and the cells can be damaged or destroyed. In extreme cases, stress induced effects can result in eggshells that have excess deposits of calcium - a sort of powdery "bloom" on the surface and result in misshapen eggs. Relocation stress is known to have effects on the visual appearance of eggs produced; increasing the incidence of calcium coated and checked (misshapen) eggs.

Major types of relocations, such as movement from one type of housing to a completely new housing environment, can produce severe visual defects of the egg.

Environmental Temperature: One of the factors contributing to poorer eggshell quality in hot weather is inadequate feed intake. Eggshell quality is somewhat compromised during summer months. During exposure to warm environmental temperature, the hen reacts by increasing its rate of breathing (panting) in order to cool itself. This causes the lowering of CO2 in the blood and produces a condition termed "respiratory alkalosis". The pH of the blood becomes alkaline and the availability of calcium for the eggshell is reduced. This disturbance in acid-base balance causes an increase in soft-shelled eggs during summer.

Temporary thinning of the egg shell may occur during periods of high ambient temperature (above 25ºC) since feed intake is reduced. The shells quickly regain normal thickness when temperatures are reduced and feed intake increases.

Respiratory alkalosis also causes increased carbonate loss through the kidney resulting in competition between kidney and uterus for carbonate ion, consequently resulting in poor eggshell thickness. During heat stress calcium intake is reduced as a direct consequence of reduced feed intake and this stimulate bone resorption resulting in hyperphosphatemia. This inhibits the formation of calcium carbonate in the shell gland. Also heat stress reduces carbonic anhydrase (Zinc dependent enzyme) activity in the uterus. Under heat stress more blood is shunted to the peripheral tissues with concomitant reduction in flow of blood to the oviduct resulting in poor shell quality. Lastly the ability of layers to convert vitamin D3 to its active form is reduced during heat stress.

Nutrition: There is a complex relationship between calcium, phosphorus, vitamin D3 and the hormonal system of the layer in calcium metabolism during lay. Calcium and phosphorus balance is critical for proper egg production and eggshell quality. Layer ration should be formulated with correct amount of calcium and phosphorus (usually 3.5 - 4.0% calcium, 0.35-0.40% phosphorus)
Calcium: Both excess and deficiency of calcium will negatively affect the shell quality. An egg contains almost 2 grams calcium; hence an average of 4 grams of calcium intake per day is required by a layer to maintain good shell quality since only 50 - 60% of dietary calcium is actually used in shell formation.

Calcium requirement of a laying hen is 4 - 6 times that of a non-laying hen. The egg enters the shell-gland region of the oviduct - the uterus - 19 hours prior to oviposition, and the shell does not store calcium ions to attach on protein matrix.

During the last 15 hours of shell formation, calcium movement across the shell gland reaches a rate of 100-150 mg/hr. This process draws calcium from two sources: diet and bone. Normal blood calcium level is about 20 - 30 mg/dl with a normal layer ration of 3.56% calcium or higher, while layers on a 2% calcium diet, 30- 40% of the calcium is derived from bone. It is therefore important to have pullets, prior to lay, on a high level of calcium to store it on body.

Intestinal absorption of calcium in the diet is about 40% when the shell gland is inactive, but reaches 72% when active. This time closely coincides with late afternoon or the dark hours for the layer. Having higher calcium levels in the gut during this time is important to ensure calcium is being taken from the diet and not bone. Large particle sizes of calcium sources allow calcium to be metered throughout this time.

In growers, most importantly, high calcium levels during the growth period will interfere with the proper development of the parathyroid gland by increasing gut pH, which will decrease absorption. The damage to the parathyroid would be permanent and would affect the bird's laying cycle afterwards.

Phosphorus: The phosphorus content of the eggshell is small i.e. 20mg, compared with 120mg in the egg contents. There is also uneven distribution of the phosphorus in the inner and outer layers of the shell. Phosphate ions have an inhibitory effect on the CaCO3 and bring the shell formation to an end.

High levels of phosphorus in the blood will inhibit the mobilization of calcium from bone. The absorption of calcium and phosphorus are interrelated and can be influenced by:

Source and form of calcium and phosphorus: Calcium source and particle size plays a role in calcium level in the gut when needed. Phosphorus must be in a form that is available and usable by the layer.

Intestinal pH: Phosphorus absorption is optimal at pH 5.5-6.0. When the pH is higher than 6.5, absorption of phosphorus markedly decreases. Excess free fatty acids in the diet can cause the pH to decrease and therefore, interfere with calcium and phosphorus absorption.

Calcium and phosphorus ratio: High calcium or phosphorus levels in the intestine reduce the absorption of both. High calcium increase the pH in the gut and phosphorus absorption is decreased along with zinc and manganese absorption. High plasma phosphorus decreases calcium absorption from the gut and calcium mobilization from the bone. Phosphorus is an integral part of the acid-base balance in the body. The proper ratio of calcium to phosphorus (Ca: P ratio) for growing birds is 1.5-2.0 Ca: 1.0P.

Vitamin D3 : Vitamin D3 metabolite is essential in absorption of the Calcium.

Vitamin D3 is vital for absorption and mobilization of calcium during shell synthesis. The importance of adequate vitamin D3 intake by the hen is obvious and it is essential for proper calcium and phosphorus utilization. However, excess vitamin D3 and its metabolites have not shown to benefit eggshell quality when normal hens are already consuming adequate vitamin D3 .Vitamin D3 is the major control element in stimulating calcium absorption from the intestine. This effect is facilitated by the synthesis of calcium-binding protein (CBP). Vitamin D3 intake must be adequate. The function of vitamin D3 is related to its metabolite 1,25 dihydroxy D3 that is formed in the bird's liver and kidneys. Any problem that affects the integrity of these organs or the parathyroid gland will have an adverse effect on the action of vitamin D3 and thereby calcium absorption and metabolism.

Diet formulation: Shell breaking strength was greater for the sorghum diet than wheat or barley based diet and less for maize-soya diet. High levels of calcium and phytate in the diet of laying hen reduce the availability of trace minerals, especially manganese and zinc. Addition of non starch polysaccharides breaking and phytase enzymes to the feed tends to improve eggshell quality.

No deleterious effects on egg and eggshell quality were observed when levels of chloride and magnesium were upto three times higher than recommended levels. Excess dietary chlorine, however, decreases blood bicarbonate concentration, which plays a pivotal role in eggshell calcification. Low dietary cationic-anionic balance, presence of non starch polysaccharides, mycotoxins and contaminants results in poor shell quality.
Part 1: Maintaining Egg Shell Quality
Part 2: Factors Influencing Shell Quality
Part 3: How to Improve Shell Quality

March 2008

How to Improve Shell Quality
This is a three-part series of articles analysing egg shell quality. It was written by Dr Lokesh Gupta, Regional Technical Manager, Avitech.

NEW BOOK
A comprehensive practical guide to improving egg quality.
BUY NOW Part 1: Maintaining Egg Shell Quality
Part 2: Factors Influencing Shell Quality
Part 3: How to Improve Shell Quality

Vitamnin C (Ascorbic Acid): Ascorbic acid is essential for synthesis of organic matrix (tropocollagen) of eggshell. Ascorbic acid alleviates the ill affects of heat stress by reducing the plasma cortisone level in the bird. Ascorbic acxid is a factor in the absorption of Vitamin D to the active hormonal metabolite 'Calcitriol' (OH)2D3), which stimulates intestinal absorption of calcium and thus elevates plasma calscium to a level that supports normal mineralisation of bones.

A dietary level of 250 mg ascorbic acid/kg diet of moulted hen improves the egg production and eggshell quality by enhancing intestinal calcium absorption or by resorption of bone Ca mediated through 1,25 (OH)2D3) production.

Sodium bicarbonate (NaHCO3):Hens aged 30 weeks fed with 1% dietary NaHCO3 and housed at 32ºC either in conventional or intermittent lighting programme had improved eggshell breaking strength. The improvement in eggshell quality was more in the group with intermittent lighting programme. Supplementation of NaHCO3 to laying hens at high temperatures is a means of improving eggshell quality as hens consume the additional bicarbonate during the period of active shell formation.

The addition of sodium bicarbonate or purified sodium sesquicarbonate, has shown to elevate the dietary electrolyte balance, improved acid-base balance and has a positive effect on eggshell quality.

Aluminosilicates: Results indicate as much as 40% improvement in egg specific gravity and 2.2% improvement in feed conversion by the addition of 0.75% sodium aluminosilicate to layer diets. Shell quality increased in summer but not in winter. However, care must be undertaken while selecting composition and ion exchange capacity of silicates.

Minerals: Zinc, Manganese and copper are compounds involved in the metabolic process of eggshell formation. These trace minerals work as co-factors of enzymes involved with shell matrix formation. Carbonic anhydrase, which is zinc dependant, stimulates calcium carbonate deposition for eggshell formation. Polymerase enzyme, which is dependent on manganese, forms the shell glycoprotein matrix or foundation.

Supplementing the diet with highly bioavailable minerals like mineral-amino acid complexes increases the eggshell weight and eggshell thickness. Copper affects the synthesis of shell membrane by activity of copper containing enzyme lysyl oxidase.

Dietary supplementation of zinc methionine improved the shell breaking strength. There was no improvement in shell quality where zinc sulphate was supplemented to approximate zinc concentration of zinc methionine.

Calcium: Provide extra calcium to the older hens @1g/bird in the form of oyster shell over and above normal requirement in summer months. Maintain the desired particle size of calcium source at the time of shell formation. The minimum size of calcium source to improve gizzard retention is about 1 mm. Solubility and absorption of calcium source must be major criteria. Magnesium content of calcium source must be as low as possible. Organic calcium is also a good option.

Chemicals: Injection of Indomethacin 4hr or 16hr post-entrance of egg into uterus delays oviposition and prevents premature expulsion of some soft shelled and shell less eggs. Chemotherapeutic agents like salicylic acid, aspirin reduce body temperature of laying hens during heat stress thereby alleviates its ill effects.

Management: Reducing egg breakage at farms requires constant attention to management details and proper equipment maintenance. Some methods to reduce the percentage of broken eggs are:

Provide cushioning of some type at the front of egg collection area of the cages. This will soften the impact of eggs rolling on to the collection wires and reduce the incidences of hairline cracks. Be sure that cushioning is positioned correctly to receive the eggs from the cages.

Collect the eggs at least twice a day and more often if possible. Eggs rolling down the cage floor have an increased chance of being broken if there are several eggs already in the collection area.

Maintain egg collection wires/trays in good condition. Examine them regularly for sharp edges, any foreign objects and for excessive wear and tear of the wire mesh/trays.

Ensure that eggs do not pile up; dead birds protruding from the cage often block the egg flow to the collection area and causes spilling of the egg on the floor.

Routinely check the quality and condition of the egg trays in which the eggs are collected from the cages.

Train egg collection workers for carefully picking the eggs from the cage area and gently placing them in the collection trays without slowing down the collection process.

Be sure that ventilation is well maintained and fans, if any are working properly during hot weathers. Try to provide constant ambient temperature as far as possible.

Reduce sound, activity and movement of workers inside the layer houses as much as possible to reduce disturbances to the birds.

Procure good quality feed ingredients devoid of contaminants, adulterants and mycotoxins and provide wholesome water at all times to the birds.

Reduce flies, and rats causing annoyance to the birds.

Check size, specific gravity, shell thickness routinely and if any change is observed, try to correct it by various means.
Conclusion :
Though precise statistics are not available, the economic loss due to poor eggshell quality is estimated to be Rs. 6 billion being at very conservative (assuming 150 million commercial layers and each bird losing @ Rs. 40/bird/ year due to cracked eggs). The above amount excludes the hatching eggs by breeding birds. These eggs have already been paid for the cost of production, so any successful effort to market a higher percentage means more net returns for the egg producer. The future of egg industry will go together with producer to innovate and supply quality eggs at reasonable cost.

Maintaining eggshell quality is a complex activity. it is impossible, even with current knowledge, to correct all eggshell quality problems. We can, however, make significant reductions in the number of eggs lost due to poor shell quality. This can be accomplished if one realises that no single factor is usually responsible for egg breakage. Many factors are known to be related with eggshell quality including, flock health problems, management practices, environmental conditions, breeding and adequacy of nutrition.

Part 1: Maintaining Egg Shell Quality
Part 2: Factors Influencing Shell Quality
Part 3: How to Improve Shell Quality

January 2008

Layers Production and Business Guide(Part 1)
Learn the easy way of jumpstarting your own layering business.

Chicken egg production in the Philippines is a minor industry compared to the broiler production sector that takes center stage in the Philippine chicken trade. But the chicken layer sector had the most growth between 2001 and 2002 because of the increase of chicken layers in the country.

In 2002 alone, chicken egg production contributed 3% of the total value of agriculture in the Philippines.

With the current socio-economic problems in the country, the chicken egg is one of the cheapest food products that are vastly available in the market. The chicken egg is also considered as one of the most complete food sources with high nutritional value.

Chicken egg production in the Philippines mainly serves the domestic market.

MANAGEMENT OF THE LAYER FARM

The success of the egg-production business greatly depends on successful management of the layer farm. Each factor discussed below contributes to the success of your egg production business.

Housing and bedding
Poultry housing and equipment can be as simple as a shed roof with chicken wire fencing, nests, water fountains and hand-filled feeders to an environmentally controlled fully automated cage layer house. Make sure that the birds are given adequate floor space. A maximum of three birds per square meter is recommended. Provide birds with up to 100% (depending on severity of conditions) more floor space than is recommended for temperate climates.

In the laying house, supply at least 1 nest per 4 females or at least provide one 10″ x 10″ nest for every 5 hens in your flock. Place nests 24″ above the floor and away from the roosts. Keep the nesting material clean and dry.

Lighting, heating and ventilation
Heat stress is one of the major risk factors that one must consider in layer farm management. The ideal temperature for laying hens is between 18 degrees and 29 degrees Celsius.

Air movement around birds at floor level has a beneficial cooling effect. In shade houses, take full advantage of natural breezes using paddles or circulating fans in periods of still weather and particularly during the heat of the day. In controlled environment houses, use inlets with moveable louvers which can direct moving air directly on to the birds at floor level.

In shade houses, natural daylight must be supplemented with artificial lighting in order to obtain desirable lighting patterns which are necessary to adequately control sexual maturity. A constant or decreasing lighting pattern during rearing is essential to prevent too early sexual maturity. An increasing or constant light pattern is necessary after 22-24 weeks of age.

Brooding equipment
Poultry housing should provide clean, dry, comfortable quarters for birds throughout the year.

To brood chicks, you need adequate heat and space. The house and equipment should be clean and in good repair.

Set up and warm the brooding area before the chicks arrive. Chicks will need a warm, draft-free location with proper ventilation and access to clean water, appropriate feed and protection.

The normal brooding period, when heat is required, is from the time chicks hatch until they are about six weeks old. Chicks may be brooded many places on the farm. The main requirements are adequate space, a reliable source of heat and proper ventilation.

A brooder house measuring 10 by 12 feet will take care of 120 chicks to eight weeks of age. The chick guard ring is 12 inches high arranged in a circle 6 feet in diameter around the brooder stove. The feeders are placed in a spoke like arrangement radiating outward from underneath the outer portion of the brooder canopy. This provides chicks access to feed and allows them to move freely in and out from the heat source.

Feeding equipment
The mechanics of feeding are nearly as important as the feed itself. Supply enough feeder space so that all the birds can eat at the same time. When space is limited, some birds don’t get enough to eat. Keep feed available for the birds constantly. Meal feeding (giving a limited amount of feed several times each day) can reduce productivity if not managed carefully.

Place feeders so the trough is at the level of the birds’ backs. This practice reduces feed spillage, which encourages rodents, wastes feed, and costs money.

Watering equipment
The distribution of waterers should be such as to minimize the distance any bird has to move in order to drink; ideally, both feed and water should be distributed so that no bird has to move more than 1 1/2 meters to get its requirements.
Whenever possible, use a water supply such as well which provides cool water. Bury or insulate water pipes to maintain the original coolness. Additionally, supply troughs in which breeders may dip their combs and wattles so that evaporation of water cools the blood supply in the combs and wattles. In extremely hot weather, do not place drugs or other substances in the water which might decrease its palatability.

Miscellaneous equipment
For large scale farms, a feed mill is usually used to automate the distribution of feeds. Feeds are distributed using an auger system. Egg transporting mechanisms are also used to minimize the occurrence of human egg handling. These automatic egg collectors are also used to place the eggs into plastic trays that will carry the eggs into the processing and sorting facility via a large overhead belt.

Dead bird disposal
Disposal of dead birds on the farm continues to be a challenge from the standpoints of cost, environmental safety, biosecurity and practicality. While we, hopefully, have to deal with only a relatively small amount each day, disposal or preservation must also occur daily in order to meet the above challenges.

Burial has been the method of choice for years because of its low cost and convenience. A deep pit with inside framing and a tight-fitting cover can be constructed, or an open trench prepared by a backhoe can be progressively filled.
Incineration is probably the most biologically safe method of disposal. It creates only a small amount of benign waste that can be easily disposed of and does not attract pests. It is also a serviceable option where a high water table or soil type precludes excavation.

Biosecurity
As a bird owner, keeping your birds healthy is a top priority. Your birds can become sick or die from exposure to just a few unseen bacteria, viruses, or parasites. In a single day, these germs can multiply and infect all your birds. However, by practicing biosecurity, you can keep your birds healthy.

Restrict access to your property and your birds. Consider fencing off the area where your birds are to form a barrier between “clean” and “dirty” areas. The clean area is the immediate area surrounding your birds, and the dirty or buffer area must be considered to be infected with germs, even if the birds appear healthy and disease free. Allow only people who take care of your birds to come into contact with them.

Scrubbing your shoes with a long handled scrub brush and disinfectant will remove droppings, mud, or debris. Clothes should be washed in a washing machine with laundry detergent. Wash your hands thoroughly with soap, water, and a disinfectant before entering your bird area.

Keep cages, food, and water clean on a daily basis. Clean and disinfect equipment that comes in contact with your birds or their droppings. That includes tools such as feed scoops, shovels, rakes, and brooms. All manure must be removed before disinfectant can work, so clean surfaces with soap and water first. Properly dispose of dead birds by burial or incineration or take them to a landfill.

FLOCK CARE AND MANAGEMENT

Chick quality
Healthy flocks start from healthy stocks. So from the start, choose only healthy chicks for the farm. Do not acquire chicks that have wet vents and dull eyes. Characteristics of healthy chicks are dry, fluffy feathers, bright eyes and alert and active appearance.

Brooding
Sufficient heat should be provided to keep day-old chicks warm during the day or night. Abrupt changes in brooder temperature should be avoided during the first two weeks.

Provide adequate space for chicks as they grow. Overcrowding is one of the factors affecting poor growth. Also provide a good light source, as a well-lighted brooder encourages chicks to start feeding. Also prove good ventilation for chicks to avoid future respiratory diseases. Egg-type chicks should be transferred from the brooding house to the grower pens at six to eight weeks old. They are then transferred to the laying house when they reach the age 16 to 18 weeks old or three weeks before they lay eggs.

Make sure to provide anti-stress drugs, vitamins and minerals to the birds two to five days before and after their transfer. Also make sure the bird houses are thoroughly cleaned before the birds are transferred.

Commercial layer strains in use today yield high numbers of productive pullets when reared under recommended breeder guidelines to be at target body weights at the desired time of reaching sexual maturity. The only selection in most instances is to remove deformed, unhealthy, and grossly underdeveloped birds when the move is made from the growing to the laying house. In the FFA (Future Farmers of America) judging contest there is a class of pullets evaluated on their production potential using the following guidelines.

The head should be moderately long and well-filled in forward to the eyes to avoid a crow-headed appearance. The face should be clean-cut, smooth and free from wrinkles. The comb should be large and bright red in color. The eyes should be large, bright, and prominent.

The pullet should be fully feathered with plumage of good quality. Shanks should show a good healthy color, but place no emphasis on color intensity with birds of this age. Feet and toes should be completely normal and the bird should be well balanced on her legs.

The body should be deep, broad, and well developed, with a heart girth of ample circumference. The keel should be of good length and the back should be relatively long, broad, and flat.

Sexual maturity should be expressed by size and development of the comb and wattles. Early sexual maturity should not be encouraged and size of development should be preferable to sexual maturity.

Layer hens may start laying eggs at age 20 to 22 weeks. They will reach maximum egg production at age 30 weeks to 36 weeks. Egg production of pullets older than 36 weeks may decline then level off. It is also during the first year that layer hens undergo the process of molting. Poor layers will molt early, and late molters are generally the good layers. Layer may produce 10% to 20% less eggs during the second year of production. However, they will also produce larger eggs.

Nutrition and formulating feed for the layer flock
Nutrition and feed are very important factors in ensuring the good performance of hens. Make sure you provide the flock with proper feeds and nutrients to get quality eggs during harvest.

Feed requirement
Feed newly hatched chicks a starter diet until they are about six weeks old. Starter diets are formulated to give proper nutrition to fast growing baby chickens. These feeds usually contain between 18% and 20% protein.

It is not necessary to feed “meat bird starter” to young layer chickens. Diets formulated for starting meat chickens are higher in protein (22% to maximize growth, which is not necessary or desirable for egg laying chickens and is higher in cost. Once the birds reach about six weeks of age, substitute a grower feed for the starter. Grower feeds are about 15% or 16% protein and are formulated to sustain good growth to maturity.

After about 14 weeks of age, you can substitute the grower feed with developer feeds if they are available. These feeds are lower in protein than grower feeds (14% to 15%) and are formulated to prepare young chickens for egg production. Remember, these two feed types are virtually interchangeable; either one can be fed to chickens between six weeks of age and the beginning of egg production.

Once your chickens begin laying eggs, you can choose between layer and breeder feeds. Your choice of feed at this stage depends on how the eggs will be used.

Layer feeds are formulated for chickens that are laying table eggs (those used for food). Layer feeds contain about 16% protein and extra calcium so the chickens will lay eggs with strong shells. Start feeding layer feeds at about 20 weeks of age or when the first egg is laid, whichever occurs first.

Breeder feeds are formulated for chickens that are producing eggs for hatching. These feeds basically are layer feeds containing slightly more protein and fortified with extra vitamins for proper chick development and hatching. However, use of breeder feeds is somewhat questionable for the small flock producer, since the increased cost may not be justified by the potentially slight increase in hatchability.

Nutrient requirements
What we feed our chickens is very important. Chickens use feed for two main purposes: as an energy source to maintain body temperature and to carry on activities such as breathing, walking, eating and digesting the feed and as building material for the development of bone, flesh, feathers and eggs. The feed that chickens eat is made up of water, carbohydrates, fats, proteins, minerals and vitamins. Each nutrient serves a special need.

Carbohydrates make up the biggest share of the poultry diet. In the form of starches or simple sugars, that are needed for body maintenance and energy. Important sources of carbohydrates in poultry feeds are corn, milo and various other grains.

Proteins are complex compounds made up of amino acids. Feed proteins are broken down into amino acids by digestion and converted into boy proteins. Body proteins are used in the construction of body tissue. Tissues that mainly consist of protein are muscles, nerves, cartilage, skin, feathers and beak. The albumin (white) of the egg is also high in protein.

The mineral portion of the feed is inorganic matter. Minerals, especially calcium and phosphorus, help build bones and make them strong and rigid. Laying hens also require minerals for eggshell formation.

Grains are low in minerals, so supplements are necessary. Calcium, phosphorus and salt are needed in the greatest amounts. Bone meal and defluorinated and dicalcium phosphates supply additional calcium and phosphorus. Ground limestone and oyster shell are good calcium sources. Trace levels of iodine, iron, manganese and zinc are also included in mineral supplements.

Vitamins occur in feeds in small amounts, but they are absolutely necessary for growth, reproduction and the maintenance of health. They occur in feedstuffs in varying quantities and in different combinations Vitamin A is necessary for the health and proper functioning of the skin and lining of the digestive, reproductive and respiratory tracts. Vitamin D plays an important role in bone formation and the metabolism of calcium and phosphorus. The B vitamins are involved in energy metabolism and in many other metabolic functions.

to be continued…

Part 2 –> Layers Production and Business Guide (Part 2)

Layers Production and Business Guide (Part 2)
Chicken egg production in the Philippines is a minor industry compared to the broiler production sector that takes center stage in the Philippine chicken trade. But the chicken layer sector had the most growth between 2001 and 2002 because of the increase of chicken layers in the country.

In 2002 alone, chicken egg production contributed 3% of the total value of agriculture in the Philippines.

With the current socio-economic problems in the country, the chicken egg is one of the cheapest food products that are vastly available in the market. The chicken egg is also considered as one of the most complete food sources with high nutritional value. Chicken egg production in the Philippines mainly serves the domestic market.

Feed compositions
The correct formulation of feed depends upon local conditions. It requires knowledge of the relationship between energy content of the feed and the amount of feed consumed daily. With correct formulation the latter will contain the correct daily allowance of protein, vitamins and minerals. Some vitamin supplementation can be done via the water and a continuous level of vitamin supplementation is virtually essential during all period of heat stress.

Water is the single most important nutrient that chickens consume. Therefore, it is necessary to provide adequate amounts of clean, fresh water daily during growth and egg production. Birds will drink between two and three times as much water by weight as they eat in feed. Their consumption of water increases in warm weather.

Sanitation and waste management
Maintain only a very shallow layer of litter on concrete floors. This will maximize any cooling effect which the concrete floor may have on the birds through absorption of body heat. Dry, dusty litter can cause severe irritation and damage to the eyes of chickens. Avoid dustiness by sprinkling water generously on litter at regular intervals. This spraying can, during extremely hot, dry spells, be advantageously extended to the birds themselves and the feed.

Vaccinations and control of common pests and diseases Many bird diseases can be difficult to diagnose. The list below includes some of the things to look for that signal something might be wrong with your birds. Early detection of signs is very important to prevent the spread of disease.

Watch out for the following signs of disease:
• Sudden increase in bird deaths in your flock
• Sneezing, gasping for air, coughing, and nasal discharge
• Watery and green diarrhea
• Lack of energy and poor appetite
• Drop in egg production or soft- or thin-shelled misshapen eggs
• Swelling around the eyes, neck, and head
• Purple discoloration of the wattles, combs, and legs (Al)
• Tremors, drooping wings, circling, twisting of the head and neck, or lack of movement.

Proper handling of vaccines should be practiced. The quality of a vaccine cannot be guaranteed if the product is mishandled or improperly used after it leaves the manufacturing plant. All vaccines are labeled with instructions for use and dates of expiration.

Suggestions are listed below for an effective vaccination plan for your flock:
1. Rotate vaccine stock. An outdated product may have deteriorated.
2. Each vaccine is designed for a specific route of administration. Use only the recommended route.
3. Do not vaccinate sick birds (except in outbreaks of laryngotracheitis or fowl pox).
4. Protect vaccines from heat and direct sunlight.
5. When using the drinking-water method of vaccination, be sure the water is free of sanitizers and chlorine. Live-virus vaccines are readily destroyed by these chemicals.
6. After vaccinating, burn or disinfect all opened containers to other poultry.
7. Hatcheries and poultry suppliers are usually the best sources for vaccines. Be sure to carefully follow label directions when vaccinating.

Layers Production and Business Guide (Conclusion)
Learn the easy way of harvesting, grading, handling, storing, transporting and marketing for your layering business.

Harvesting poultry is one of the crucial steps in the egg production process. Make sure you have the facilities to ensure proper harvesting of eggs. Eggs should be collected regularly, more so during hot weather. You may collect the eggs often (2-3 times daily). Eggs should then be transferred immediately to the egg cooling room which can be located on the farm site.

If eggs are to be hatched, insulated vans should be used to transport eggs to the hatchery. Daily fumigation of eggs is also recommended.

Hen-day production computation
You can compute your daily production percentage using the following equation:

Hen-Day daily production = Number of Eggs Produced on Daily Basis DIVIDED BY Number of Birds Available on the Flock that day

To compute your produce over a production period, you can use the following computation:

Hen-Housed Egg production = Total Number of Eggs Produced by the Flock DIVIDED BY Total Number of Hens Housed

Egg quality should be maintained throughout the handling and storage of the eggs. The people involved with these processes should be informed about the physical structure and chemical composition of eggs and the factors that affect their quality.

Grading
Grading is one of the important steps in marketing eggs. In this process, eggs go through identification, classification and separation. Grading allows you to set different prices for different sizes and quality levels of eggs. High quality eggs may be priced higher, while eggs with small blood spots may be sold to customers such as bakeries.

Factors to be considered in grading eggs are appearance, internal quality, size, color, and the soundness of the shell.
Eggs are also classified by size (in grams) and the US has the following standard:
• Jumbo = 70 g and above o Extra large = 65-70 g
• Large = 56-65 g
• Medium = 49-56 g
• Small = 42-49 g
• Peewee = 35-42 g

Candling
Quality testing of eggs can be done by candling method. This is the process in which eggs can be tested internally and externally without breaking the egg or causing it damage.

This process can be done by using a candle in a dark room and examining the egg’s interior quality in front of the flame. Another way of Candling is by use of an electric light bulb that has been placed inside a box. Place a hole with three centimeters on the box. This hole is sufficient for eggs 40 to 70 grams in size. A light beam will glow from the hole and allow for egg inspection.

Packaging
Packaging shell eggs is an important part of marketing and eventually, the business. Breakage, shell damage and spoilage can cause severe losses to the farm. These losses can be prevented by proper packaging.

Packaging of shell eggs must allow the eggs to have access to oxygen. Contamination and tainting can be prevented by using odorless and clean packaging. Remember to use packaging materials that can endure your handling, storage and transport methods to protect the eggs from damage and deterioration. Also remember to use packaging materials that allow the consumers to see the eggs they are buying as customers often want to see the product they buy.

Clean odorless rice husks, wheat chaff or chopped straw may be used in packing eggs in a firm walled basket or crate. This packing method is appropriate for short distance transport.

Filler trays are another form of packaging for eggs. These are especially favorable because they allow eggs to be inspected without having to touch them. Filler trays may be made of molded wood pulp, sawn wood, cardboard or plastic. Plastic is commonly preferred as they can be washed and reused. Each tray usually carries three dozens (36 pieces) of eggs.

The third kind of egg packaging is the retail pack. This type contains two to a dozen eggs. This can be made of cardboard or plastic, and is often the packaging consumers see at the supermarket. This packaging type allows easy handling and inspection of eggs by the retailers and consumers.

Packaging should also contain labels which include information such as the grade, weight, size and expiration date of the eggs.

Storage
Egg storage for future consumption has been practiced for hundreds of years. There are simple steps in storing eggs to prevent deterioration, which includes simple storage in proper temperature and proper sanitation.

Eggs for storage must not be washed or wet and should be clean. Dirt and bacteria that enter the porous shell can cause it to decay. Use dry abrasives for scraping and brushing but take care not to weaken the shell and do not increase evaporation.

Shell oiling is a process that can greatly reduce losses by evaporation when eggs are in cold storage. Special odorless, colorless, low-viscosity mineral oils should be used. If eggs should withstand high temperatures, they should be oiled from four to six hours after lay. Eggs that are to be stored at a temperature of 0°C should be oiled 18 to 24 hours after lay. Eggs may be oiled by hand dipping wire baskets or by machine. Make sure that the temperature of the oil is at least ii° C above that of the eggs. Before the oil is reused it should be heated to a temperature of 116°C to prevent bacteria survival. The oil should then be filtered. The oil reservoirs should be cleaned properly. In terms of appearance oiled eggs differ from other eggs only in the slight shine left on the eggshells by the more viscous oils. Make sure that the packaging material, as well as the storage room should be clean and odorless. Also make sure that there is air circulation in the room.

In hot weather, eggs should be stored at low temperatures. Temperature should be maintained at 13°C or lower (usually between 10° and 13°C). The relative humidity should be between 80 and 85% at a cold storage temperature of -1° C. At cold storage temperatures of about 100 C the relative humidity should be between 75 and 8o percent. Where eggs have been oiled, less attention can be paid to the humidity level. The average storage life for eggs is between six and seven months.

Transport
Transport of eggs should not be delayed to minimize spoilage. This is one of the most important aspects of marketing arrangements. Generally, long distance transport should be made by using refrigerated trucks. Aside from monitoring temperature, eggs should also be protected from contamination during handling. Use packaging materials and transport containers that protect the eggs well from breakage. Egg trays and containers should also be stacked well and secured to protect them from excessive shaking in transit.

The business
Just as in any business, the layer farm should keep records to monitor its production costs and profits. Here are the costs to consider before starting an egg production enterprise:
1. Rearing - rearing brooders until they become layers
2. Housing - building or maintaining laying house and brooder house
3. Equipment - cost of miscellaneous items such as feeders, buckets, fans, etc.
4. Feed - total feed used during the year
5. Labor - labor costs for managing the farm
6. Vaccinations - medicines and veterinary expenses
7. Mortality - loss of birds due to disease, etc.
8. Various expenses - lighting, water, and other unexpected expenses

Marketing for eggs
There are two ways to market table eggs: using direct marketing, or marketing through middlemen or intermediaries. Marketing through middlemen is the more popular method and the more advisable one because this gives the farmers the opportunity to concentrate on the farm and production as compared to spending time on marketing and sales. Just remember, the most crucial part of marketing is meeting the demands and requirements of customers, and these usually rely on production, handling, storage, and transport of goods.

The four ways to conduct direct marketing are: sales from the farm, door-to-door sales, producers’ markets, and sales to local retail stores.

When a farmer directly sells from the farm, he gets the advantage of zero marketing costs, and consumers are assured of fresh eggs with almost no quality loss from transport. However, the farmer is not assured that the consumer will be willing to travel to his farm to avail of the eggs at regular market price as compared to farm-gate price.

Door-to-door selling affords the farmer to command a higher price for the eggs for the added service of bringing the eggs to the consumer’s doorstep. However, this does not assure sales until the farmer gets regular customers who order the eggs.

It is not advisable for the farmer to use producers’ markets alone to sell eggs because the main advantage of this market is that the farmer would have reduced the price of eggs greatly toward the end of the day, and the eggs would have already been exposed to the environment and temperature of the market.

Selling directly to local shops, institutions and businesses like restaurants, hotels, schools and hospitals would require a prior agreement and contract. The farmer should be able to meet the quantity and quality demand of the customer organization.

Marketing with middlemen
Marketing with the use of middlemen or intermediaries is most beneficial for the farmer because he will only need to make the deal with the middleman and will not need to spend time and money for the marketing of eggs. These middleman would have been experienced in marketing eggs and already have contacts to whom they can sell the eggs as well as knowledge of the egg market. Middlemen also pay for the eggs immediately and will take care of transporting the eggs from the farm.

Marketing costs and pricing
Costs to be considered during marketing are: packaging and storage, handling, transport, product losses, fees and taxes, and unexpected costs from unforeseen incidents such as derailment in delivery and such.

Pricing for eggs fluctuates during the year, depending on factors that affect production and eventually supply and demand. But farmers should always keep in mind to maintain a steady supply of eggs to maintain stable prices.

Profit can be calculated at the end of the year, when farmers can calculate total sales minus production and marketing costs.

Trade associations
Trade associations are helpful to producers because they are able to conduct dissemination of information and technology to its members. Trade associations also come up with the standard of quality farmers should produce. Overall, trade associations are beneficial to producers because they look out for the producers’ interest.

In the Philippines, there is the National Federation of Egg Producers of the Philippines or Egg Board which has organized two egg shows to date.

Part 1 –> Layers Production and Business Guide(Part 1)

Part 2 –> Layers Production and Business Guide (Part 2)

Pinoyagribusiness

LIVESTOCKS => POULTRY => Topic started by: mikey on June 27, 2008, 11:39:18 AM