Yes, I also suspect she has gapeworm but the other chickens don't show the same symptoms so I'm not sure. The symptoms of the chicken that recently died were lethargy, loss of balance, twisted neck, and loss of weight.
Thanks! She has been coughing for about 2 months but only about a few times a day. However, the weird movements with her head have only been going on for a few days. I think her crop is clearing overnight since it was smaller than yesterday's.
I have a black australorp that is around 6 months old and just started laying eggs about 2 weeks ago. Recently, she constantly makes coughing sounds and keeps on moving her head side to side and swinging her head around. She also has some grumbling sounds that are not coming from her mouth but...