I have a peacock that is stretching his mouth open and acting like he is having trouble taking a breath. I looked it up and it sounds like gapeworms, however he is also losing his blue neck feathers and I don't know what that is from. I gave him .5cc of ivermectin on dog food and he ate it up, how long until it takes effect? Also, does anyone know what could be causing the feather loss on the neck?