chickens killling eachother?

Sadly yes,chickens can kill each other. If your chicken was injured or hurt and had blood that the other chickens so it is likely they did attack her.It also might have something to do with her pecking rank.Has she been bullied by other chickens before?It could have just been a predator though.Do you have a predator proof coop?Do they free range?If so,It could have likely been a snake,hawk,or racoon.So sorry for your loss.

 

Possible but check to see if dead bird had any health problems, besides being dead. Was it thin?

 

True,it could have been health problems but it sounds like a pretty sudden death.

 

Does it look like its been attacked? I would imagine if it had been pecked to death it would be pretty beat up looking.

If it looks like normal with no damage its hard to imagine how they could have killed it without leaving a mark. In that case if probably put it down unexplained death. Could be heart, tumour anything.

 

I have a lot of chickens, and have had them for many years. Sometimes a chicken just drops dead. No symptoms, no warning, just one morning you find a dead bird in the shavings. I see one about every 18 months or so.

If there's no damage to the dead chicken, then she just died, cause unknown. It happens. You'll have mortality in any group of livestock.