Help missing feathers and skin on her back

[Quilbea]

Hi we have a plymouth rock that has all her back bottom of vent feathers all gone and seems like the skin is gone also. She is 11 months old. I was told that it looks like we are looking at her egg sack because the skin is missing. We cleaned her and sprayed blue kote and have also moved her into a separate area because the other chickens were pecing at the wound. The wound feels dry and crusty. Any help as to what it could be and what to do is appreciated. We checkec for mites and she is clean.

 

[azygous]

The bright red skin is a symptom of raging bacterial infection. In that area, it would likely be from salpingitis, an infection of the oviduct, usually E.coli, which entered through the vent at some point. Antibiotics may be helpful if it's early in the infection.

Have you noticed her "laying" some odd little, waxy bits, maybe half and inch long? That would be pus from the infection. How is her behavior? Is she acting normally or is she lethargic?

 

[Quilbea]

Just went to check and her poop is somewhat runny and light colored but no waxy bits. She is eating and drinking but no egg someone who raised chickens said it looks like we are looking at her insides that the skin is gone and that's the egg sack we are seeing and she will most likely die.

 

[Quilbea]

Where would i I get the antibiotics?