have not been able to get my chickens well

[pinker]

For the past month my rooster mainly keeps getting a respritory infections i thought he was better. Then he started coughing and mouth breathing weezing. I have taken all of the chickens to the vet. he gives them shots of antibotics. helps for a while then the illness is back. I have disinfected the pen several times change the water every day. The three hens only get clear discharge out of nose cant think of proper name. by my roo gets hit hard trouble breathing .sounds like he is snoring. Help please

 

[speckledhen]

Antibiotics won't help a virus, which is probably what he has. And most of those make the bird a carrier for life, so they are never truly well. Honestly, it's best to cull him because he'll make others ill, too.