Be careful with that hydrogen peroxide. It will NOT kill the maggots and actually can contribute to killing the flesh if you use a lot of it over time. My vet said it is nearly impossible to kill the maggots because anything you could use on them to kill them is not good for putting in an open...
Here's my thread.
https://www.backyardchickens.com/forum/viewtopic.php?id=11007
It's a long one, so I'll try to give you the Reader's Digest condensed version.
Something grabbed one of my chicks through the fence and injured her wing. I took her to the vet (non-avian specialist) and she...