Today I went down to the coop and found one of my 5 remaining Cornish x's sluggish. The other birds have picked on it so it's baldish. Right now its sluggish and gasping for breath. I've had this happen a week ago with another and I've assumed was CHF. Today I'll be butchering this one too. Thoughts? All my other birds are healthy and eating well. I have 28 birds total. The cornish Xs are 6 or so weeks old.