So can someone clarify please. Just being around the flies would attack? or do they have to be injured first or what? I see flies around mine fairly often, especially if I have them caged up for the day and they drop a nasty deuce or two in close quarters. Wow, this is shocking.
Aaron
The flies normally lay eggs on feces or rotting meat, which the maggots will then feed on. They're like nature's garbage disposals and are still used in hospitals today for cleaning necrotic wounds of dead tissue.
However, when a chicken has feces stuck to their vent, or if they sit in feces that flies have laid eggs in, they will eat through the feces until they have nothing left to eat, in which case they will turn to the chicken out of desperation.
I've personally never seen something like this in an animal that didn't have a prior injury/condition. I've seen it twice in chickens and a few more times in ducks. Once in a goose.
In the first chicken case, she had an injury to the right of her vent. It became infected due to the feces clinging to the feathers, and the maggots went to work. In the other, it was a case of pasty butt that led to maggots.
In the first case, however, the maggots actually managed to save the hen's life. Her infection likely would have gone septic and killed her if the maggots hadn't been eating away at the rotting tissue and preventing the infection from spreading.
Both hens lived. The only one we lost was one of the ducks, who simply was too weak and was eaten away at too much. He was euthanized.
Chickens are shockingly hardy, so I wouldn't be surprised if she pulls through and heals up. I had one hen, a Jersey Giant, that was attacked by a bobcat on our security camera. We thought the bob took her until she showed up two weeks later, sans one leg that was missing from the hock down. It was infected, so I kept her inside the house and simply let the maggots do their work for about two days. Once they ate away all the rotting/dead flesh, I washed them out and removed the rest with tweezers, then soaked the leg in iodine and wrapped it. It healed up just fine and looked more like a surgical amputation than a traumatic one. She was two years old at the time and lived seven more years. We called her Pegleg.