That was fly strike. The maggots were eating her flesh and would have continued to until and after they killed her. In the future if this happens you can spray the wound with an insecticide to kill the maggots. We had to treat a duck once that was on a nest too long and had her eggs break under her. The maggots were everywhere in her breast and neck. There were so many! Our neighbor is a vet and told us to use an aerosol insecticide. The worst that could happen is it would killer her. She lived to sit on another nest!
