Lavender Orpington breathing heavily

[NMfarmgirl]

Hi there, I have a dear 5 year old lavender orpington who started having breathing problems several weeks ago. The vet initially prescribed enrofloxacin and prednisolone, which I gave her for two weeks, but there was no change. I took her to the vet for an urgent care visit and he changed her medication to SMZ (which she’s had for 6 days), and I also started putting TiaGard in the water (5 days), but she only seems to be getting worse. Her behavior is otherwise completely normal— she’s eating and drinking, not lethargic, maybe just seems a little weak when I hold her. Sometimes I can’t hear the breathing problem at all, but at other times it’s loud and occasionally accompanied by slight snoring/wheezing/honking sounds. This morning was the worst— it seemed like she was panting (beak only slightly open) even though it wasn’t hot out, and her tail was bobbing. Then it stopped later and just went back to loud breathing. I don’t know what to do, I’m desperate to help her, but the cultures haven’t come back from the vet yet and probably won’t for several more days. Any help would be greatly appreciated.