I have a batch of 33 hatchery 2 week old chicks (16 Speckleds, 6 Ameracunas, 11 silkies). Initially I kept them together in a large horse trough thinking this was enough space. Two days ago I walked in to the chick room and found several bleeding chicks. One who had a tail that was pulped from multiple peckings, another had bloody shoulders, another with tail feathers gone, and it went on and on. At last count, 6 of the birds were injured enough to bleed. The "nursery" is a trough with one red 250W heat lamp on one side, large long chick feeder and several waterers up on bricks to keep them as clean as possible. They can definitely reach them without issue. I separated out the chicks that were injured, they were treated with blue colored antiseptic that I got from the nice people at tractor supply. Stuff stains like crazy, my hands are still purple! Stopped the bleeding and kept the chicks from being red and thus being picked on by the other chicks. The one that was pulped was put into recovery for a couple days and is now eating, drinking and behaving like a chick again. I then separated out the chicks, 10 silkies in a 54 gallon rubbermaid container, 6 in another 54 gallon and the rest back in the trough. Added chick bricks, a couple boxes to play in, a pan that had some dust to bathe in and other chick diversions. After a few days my sickly chicks were active and reintroduced into their flocks with the exception of the pulped one, that one was placed with the 6 Ameracunas making that one contain 7. All was going great until I started hearing loud peeps. Sounded like pain coming from the trough. I watched a while and realized that one chick, just one chick, was behaving a lot more aggressive than the others. Yanking out blood feathers, ripping out tufts of fluff and generally being nasty. I put this one in a clear box and kept it aside a few days. Today I tried to reintroduce the chick. I marked it first with purple on the leg to make sure I knew which one it was. Within minutes it became evident that it was back to being nasty all over again. This bird ran around like crazy at first, pushed the others away at the drinking spot, and started pecking. This was hard pecking, nothing like the other chicks do. Fur was flying and you could see the skin being pulled away. It is again alone, I can't have more injured chicks. The bird in question is a Speckled Sussex which is not known to be particularly aggressive and I own three beautiful ladies that have been great birds since I raised them from chicks. It seems so out of character for this breed. After reading my story, what would you do with the chick in question? Our current thoughts are to cull the bird, wait until it feathers and put it out with the big hens to learn it's place, or just raise it alone. If anyone has any more suggestions or recommendations I would love to hear what you have to say. Thanks for reading my story!