There is one problem with we farmers, I haven't used lasota or any other vaccination drugs against virus. But I practise ethical and I haven't had attack of those virus before neither have I experienced it for many years, some of us belive when we vaccinate against newcastle and gumboro that the would not come again this definitely a lie. To me I don't believe on vaccination of birds would stop a disease except for merek which is only on first day. I treat my birds Newcastle and gumboro even when the are negative to it i treat them and it works for me, because I treat it makes it not to come to existence talk of vaccine failure. Why Newcastle killed all your birds is because you vaccinated and forgot to treat and ignorant to know the vaccine might fail but when you treat its final according to the treating schedule.
How to treat Newcastle disease in poultry today

But I learnt that keeping birds on drugs for a long time affects them adversely.

Oga, i was tempted to click buh naa! I pray u dont witness serious newcastle outbreak, i'm very sure your mindset would change in a flash when they come down

PrincewithGod:
But I learnt that keeping birds on drugs for a long time affects them adversely.

I have been using this method and it works for me plus other farmer whom I thought, it would not affect your birds because you are to do this only for 48days if you are keeping to 10,11,12 and above weeks but if you are selling at 8weeks you have to withdraw at 15fays for customers but remember anidone anti-coccidcisis has no side effect expect dramacine which had 15days withdrawal. If you treat your birds against Newcastle it would be hard for it to affect them but vaccinating might fail.

Example we take malaria drugs each month even when we are not sick to treat malaria. The intake of the drugs would kill the ones mosquito has injected in you but if you leave it to accumulate then there is problem.

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