Hello. So today I found in coop one of my 9 months old hen dead. Im curious about that, if it could probably be of my cockerels incorrect mating, + hen had virus in here, coughing, n heavy breathing. + in in the back off the comb bit biten off skin. I had seen my cockerels bite in hens comb and try to mate, hens head bending backwards, so. Anyone else had experience of this? P.S, search no predator signs. P.S.S, that hen had a rough life, when i bought it 2 months old, this one was the biten bird in the side, but we heal great and even was a heaviest hen of those sisters. P.S.S, after that one terrable night, they had coming those viruses on outside. She was only showing these signs, 'yesterday'.
If the hen showed signs of having been attacked then I'd think maybe she was bullied to death, maybe after showing signs of illness. If she showed no signs of any damage that's normal for your hens post-mating, then it's probably the illness. Biting the comb is a bit unusual but some males mate that way, but taking pieces off is not a good sign. Some males have confused mating and fighting instincts and do a bit of both at the same time, making life a misery for the hens if they don't outright kill them. As a matter of ethical husbandry I get rid of those males and their abnormal mentalities. But of course if your hen was bullied to death it's possible it was the other hens doing it, not the males, or not just the males. However I think it's far, far more likely she died of illness, going by the description you've given. Sorry for your loss. Might be a good idea to try to match those symptoms with a disease and begin treating if necessary. If it's viral chances are your other chooks all have it too. Best wishes.