As I was loading my 9 pullets (five 4 week/four 5 week) into their transport box to move them from their brooder (a large dog crate) for some outside time, I found one of my 5 week old Arau's with a badly injured back. This was not there last night, so it must have happened this morning. From the looks of the blood stained beaks on several of the other chicks in the flock, this was not a one bird bully...and everthing I've read is true, that when chickens smell blood they quickly jump on the bandwagon. I'm not sure how to treat this wound because it's so big. Will a antibiotic cream be ok? Or peroxcide be better? Or both? Up till this morning, I've had a very harmonious flock, although I've been anxious to get them moved to their coop because their brooder is becoming a bit too crowded in my opinion. Their coop/run is being finished this weekend, and coming week. I know I should isolate this chick so she stays safe and can heal...but how should I do that? With a crate next to the other chicks? Or maybe with only one or two as companions? Thank you for any medical advice you can give me...as well as thoughts on how to segregate her while she is healing...and how long that might take.