I wasn't sure if I should post this here or in the "predators" section, but I'm sure someone will be able to help. My wife and I were on vacation this past week. Her parents were watching over our 6 hens while we were gone. Her father was over this morning before we got home around 1:30 and everything was fine. One of this morning's eggs did have a small spot of blood on one end of it. When we got home and settled we went out to the coop to let the girls out. My wife found a few more eggs with one having a lot more blood on it. We noticed only 5 come out so we went inside the coop to find one of them dead. We didn't find any blood, or holes anywhere in the coop (it's pretty tight). She was laying on her back and it almost looked like her neck was broken, it was off to the side. It may not have been, maybe she just landed like that. I brought her outside to have a better look and noticed that her vent was wide open but no markings on her body. The opening was about the size of an egg. The one egg that had the most blood on it was rather large. I've read they can strain sometimes while laying but that it's usually messy, which it wasn't inside the coop. Could it be one popped a blood vessel while trying to push it out? They've been laying for at least a few months now, so it's not like this is anything new to them. I've also read that rats can harm chickens, does this sound like anything like that? I'm really stumped. This is our fist year raising chickens and couldn't find anything in any books that we have that comes close to something like this. She died sometime between this morning and early afternoon. She was starting to become a little stiff when I picked her up. It's almost like she laid an egg and the vent stayed open. The first bloody egg was found by her dad in one of the nesting boxes, while the second bloodier egg was found in a corner they like to lay in sometimes. We found her near the roost which is a few feet away from the boxes and that corner. Any ideas as to what may have caused this? Any suggestions are greatly appreciated. If anyone needs more explanation or has any questions please ask, I'll try to answer them as best as possible. Thanks a lot!