Plain neosporin, or plain triple antibiotic ointment (no pain killer) are fine. Reapply it several times a day, to keep the wound covered with the ointment and moist, that will help healing. As long as it doesn't get infected the chick can heal up and be fine. I had a hen scalped and I separated her and treated that way, and she healed up fine. It will take some time though and the scab that forms may be very thick. It will slowly flake off on it's own as the wound heals. The chick can't go back with the others until it's healed up enough that the others won't peck at the wound. I've attached a picture of my hen, about 5 weeks after scalping, feathers are just coming in. Once the feathers all grew back, you couldn't tell it happened.
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