Last evening I went to close up the coop and found 2 of my 4 mo old cockerels almost dead. they were lying on their side and barely breathing. I could not find a mark on them. I ended up having to kill them because the were suffering. I can not figure out if a dog would have done this??? I thought I would at least fing a tooth mark. I also have an older Buff Roo, but he has been with them for quite some time and has not shown any aggression towards them at all. Does anyone have any ideas for me?