I've used Tea Tree Oil on all the animals and kids for various minor injuries, dermatitis and to make sure new birds don't get picked on when they're introduced but Wow, does that stuff work! The other day I came home to find one of my black sex links with a HUGE gash down her backside. I could literally see the bones in this deep hole and flesh and meat were hanging. But she was still walking around and even pecking at herself a little so I figured I'd give it a day. I poured Tea Tree oil full strength into the four inch long gash and then sort of smoothed her feathers down with a light coating of tea tree oil to keep the other chickens away from her. Three days, just three days later that huge gash is closed, no infection, no blood, not even a scab and my girl is just fine and apparently laid an egg this morning. I'm amazed.