Hello again everyone. That's interesting about the moderate vs heavy growth. My vet did switch to a different lab so maybe that was just the opinion of the technicians, or different practices at the new lab. I'm not sure.
Anyway I will answer a few things that have been brought up...
First, I do have a probiotic and did give it to the babies throughout their course of antibiotics and I still stir it into their chop. I will keep in mind that I should give it to them an hour or two after their dose of antibiotics. That's good to know.
Also, I do have F10 and have been using it pretty religiously. Throughout their course of antibiotics I did clean every day. I replaced all their perches with plastic ones because I did not trust that the wood perches could be disinfected enough. All their toys are also plastic for that reason. Every day I would do my best to scrub the poop off the bottom grate, wipe down the bottom tray, then spray everything until very wet, including perches and toys, taking out bowls and cleaning and then spraying with F10... Before they finished the antibiotic I also took the cages and put them in the bath tub, scrubbed them down and then sprayed liberally with F10 because I wanted to get every nook and cranny.
Should I remove every perch and toy and soak them in F10 rather than just spraying? Maybe they weren't getting wet enough, even though I sprayed heavily.
I also have used a steam cleaner and F10 to clean every surface of my home. All surfaces in my bedroom where the birds are, all hard floors, all counter tops... And all carpets and rugs with the steam cleaner, after being sprayed with F10 as well. I always feel like I'm not doing enough but I'm not sure what more I could do. I'll have to buy some more F10 soon but I still have a fair amount left and will continue the cleaning regimen. I don't really have money to throw at testing swabs around the house, though. I just took the "better safe than sorry" approach and cleaned absolutely everything with F10. In areas where birds are not located, and nowhere near, we also used a few other products that said they killed MRSA -- Lysol, for one. Also washed all clothes, sheets, blankets, towels, in hot water and bleach! We also have hand sanitizer located throughout the house and I have been wearing vinyl gloves while cleaning or touching the cages or the birds.
I am actually currently looking into locating some small cages to use as hospital cages so that I can separate them all. Kind of sad to think of doing so -- they get a lot of companionship from each other. But we have decided to test them all individually anyway after further antibiotic treatment, so it makes sense.
I still wonder whether the dose of SMP-TMZ was adequate but the vets seem to think that isn't the issue. I'm just really trying to rack my brain to see if there's anything I'm missing or not doing well enough...