As per my opinion don't bother to check the weight of your animal per stage. In the end of the day it is the final weight which is important. The animal should weight at least around 85 kgs above or at least you have an 10% or more profit.
It does not usually follows that if you have a big animal you will earn big also.
Although for scientific purposes i would just post later on the ideal weight per stage of animal. This is according to the feed manufacturer. I do not have the copy of it with me right now, so post it later.
average price (premium feeds):
booster 100-200 pesos per kilo
prestarter 1000-1200 per 25 kgs
starter 950-1100 per 50 kgs
grower 850-1000 per 50 kgs
finisher 800-950 per 50 kgs
Some product maybe much cheaper or expensive. This is just a rough estimate of the leading brands. There are more than 500 feedmillers in the philippines and they have different prices and it is very difficult to give an accurate average.
It would help if everybody could post their current feed price, brand and area.
Do visit this link about the farms in laguna and rizal
Swine Farms in the Philippines