My flock is sneezing

[GIFC2020]

So lately I've been noticing a few of my chickens have a slight sneeze/cough and I want to treat my whole flock as a precaution. There is one in particular who sounds kinda raspy and has a lot of mucus around her mouth. My main question is what to treat with, how to use it, and the proper dosage?

 

[Eggcessive]

Viruses will not respond to antibiotics, but secondary bacterial infections may be prevented, and MG or coryza may be helped. Tylan, oxytetracycline, and Gallimycin are common ones to use for treatment of symptom, but won't cure these diseases since most are chronic. The flock usually all become carriers of most respiratory diseases, so testing or a necropsy to find out what disease you are seeing may help. Here is a good link to check about common diseases including the respiratory diseases such as MG, infectious bronchitis, coryza, and ILT. http://edis.ifas.ufl.edu/ps044