You need first to check the enviromental factors that might contribute sa sakit ng animal mo.
Check the airflow, stocking density, masyado bang mahangin sa gabi, malamig, or sobrang init ba dahil siksikan sila etc.
Then in terms of vaccination you can give mycoplasma vaccine, APP, etc... better ask your local vet about these. They are in the position to recommend what vaccine to give dahil sila mas nakakakilala sa area nyo.
Vitamins would help