What illness are you planning on treating with sulfa antibiotics? There are some available for fish or pigeons over the counter, but in chickens they treat the respiratory disease coryza, coccidiosis, fowl cholera, and some gram negative bacteria in other illnesses.Isn't an RX required for Sulfa? No vets in my area take chickens at all. 2½ hour trip 1 way to the ONLY vet I'm aware of (and believe me...I've searched alot!)