I think Kitedemon is simply stating that based on the state that your snake is in, and the fact that he just came off a run of Baytril, you probably don't want to wait for a culture. I'm sure Alex would be the first one to agree that cultures are necessary to properly treat an RI.
However, that decision should be up to the vet. More often than not, when your snake is this sick, a vet will culture but will also send you home with antibiotics that he feels will work. See, it takes time to get the results of a culture, so when a snake is as sick as yours, the odds are that the next vet will take note that Baytril did not work and get you started on another med while the culture is processed.
I'm confused as to why the vet prescribed Baytril for giardia. Giardia is a protozoal disease and usually the only antibiotic used to treat it is flagyl (metronidazole) which is effective on many protozoa. Fenbendazole (Panacur) is also used. Panacur is not an antibiotic.
I may be wrong but I thought that some species of giardia are actually native to the intestinal tract of snakes.![]()