Help im not sure whats wrong.

[Noobchickenlover]

Ive had chickens for a long time. We recently got some new chickens to add to our flock. We got them all from different places. Two of them had mites. And the rest seemed totally fine. We have had them for about a month now. 1 of the chickens who had mites (we didnt introduce to out flock) passed away from an unknown illness. Now my flock is starting to get sivk and die one by one. We have been putting apple cidar vinegar in the water. To try to prevent them from getting sick. We go out there at least twice a day and quarentine any who are looking sick. But it keeps happening. Our flock rooster is now been sivk for a few days. You can hear the liquid in his longs. And he isnt eating a whole lot ive sat with him to help him drink which he seems fine with. But im not sure what to do. And i have WAY to many chickens to give every single one antibiotics.

 

[coach723]

I would recommend that if you lose another one, send it in for necropsy, so you can find out exactly what is going on. It sounds like it may be respiratory in nature, but necropsy will confirm that. There are some other things that can weaken them and leave them vulnerable. Since you brought new birds in, one of them may have brought it in with them. Some of the virus's are chronic and symptoms will come and go, and they often become symptomatic during times of stress, like moving to a new place. Most of the virus's are very contagious and will spread quickly in a flock. That is why it's recommended that new birds be quarantined, for 30 days, before mixing with a existing flock. Knowing exactly what you are dealing with will tell how to deal with it going forward. If vet care is an option, they may be able to help. If you lose another, then refrigerate (don't freeze) the body and below are some resources, by state, for necropsy in the US.
https://www.metzerfarms.com/PoultryLabs.cfm
https://www.aphis.usda.gov/animal_health/nahln/downloads/all_nahln_lab_list.pdf