About 3 Days ago my dads small yorkie took a bite of feathers out of my buff Orpington’s fluffy butt. I thought it was just feathers... today I can tell it’s worse than I thought and it looks infected... like she got more than feathers. Since her feathers are missing, she can’t get on the roost to stay warm so I put her up there with everyone at night and she jumps down in the morning. I noticed while putting her on the roost, her skin looks infected and there appears to be pus What can I do for her? Our vet doesn’t do chickens. Can you purchase antibiotics somewhere?