My 18 week old barred rock pullet had a poo encrusted behind yesterday. Almost completely covered up but not quite. I peeled all of this off, which also took off the skin, washed it off with water, dried off with clean paper towel and applied the purple dye with the blotter. Today, her behind stinks like crazy, as it did yesterday, she acts a little droopy and I am unable to tell you whether she is eating or drinking. Is there an antibiotic at Tractor Supply that I can purchase to give orally, or intramuscularly or add to water to help her. My flock is 28 strong plus 3 pekins and she is at the absolute bottom of the pecking order. I am afraid to separate her again (previous injury) for fear she will be even more abused when re-introduced to the flock. Advice welcomed!