Sorry to hear it. Sometimes that's just the way it goes.
If you are not too squeamish, you could consider doing your own autopsy. Then you can look for things like tumors, worms, infected organs and other stuff. It might give you a clue and perhaps give you a chance to treat the flock if you find anything.
If you are not too squeamish, you could consider doing your own autopsy. Then you can look for things like tumors, worms, infected organs and other stuff. It might give you a clue and perhaps give you a chance to treat the flock if you find anything.