Awww poor baby, so sorry she isn't well. I've had very few occasions with a messy poopy butt & it was usually a Homing Pigeon, never any of my chickens, yet anyway. So I didn't even know what vent gleet was, I just looked it up, very interesting, because when my pigeon had poopy butt it was coccidiosis, and the treatment was enrofloxicin. But vent gleet would get worse with antibiotics, since it is a yeast infection. I guess the 1st issue is proper diagnosis, so we'd know how to proceed & treat. Can you take a fecal sample to a vet for diagnosis? Unless you happen to have a microscope handy? Do you smell just a stinky odor or can you also detect that fermentation smell?
This is interesting info on gleet I found.
https://www.birdhealth.com.au/vent-gleet
This is info on coccidiosis
https://www.acreagelife.com/hobby-f...chickens-transmission-diagnosis-and-treatment
Both result in a "stinky poopy butt" but I wonder, does the gleet have really strong or faint fermented sauerkraut odor? I don't like trying to diagnose my birds simply by appearance and smell, but if the nearest veterinarian is 3 hours away sometimes ya gotta do what you gotta do, & I've been darn lucky. I used to have a wonderful, knowledgeable man to call, he was known as Dr. Pigeon, they still sell Dr. Pigeon products at Foy's, but he passed on a few yrs ago, he took phone calls from all over the world & would help anyone with any animals, he talked me through successfully stitching up my 1st hawk attack victim decades ago, really miss that kind, humble soul! Sorry, off topic I know, but I learned so much from him, he was the sweet grandpop with a lifetime of knowledge & old home remedies that really worked.
I sure hope your hen will be OK!
Good luck to you & your little sweetie, hopefully she will be strutting around with a fluffy butt instead of a crusty butt very soon!
