Well, the Nutribac probiotics arrived today (ordered 18 January) - I'd almost given up on them, but 6 weeks isn't unheard of (it is a long way, I presume the UPS man was rowing....). Tonight he gets tube fed a beaten egg with Nutribac, and my fingers are crossed he might start eating again.
He's been refusing solid food again (and I've tried a variety), so I tube fed him a home made shake of blended chicken gizzards and egg last week and he spent a very jolly half hour vomiting it up all over me. Lovely. Won't be doing that again.
He did pass a HUGE and very smelly stool, (maybe lubricated by the beaten egg...) so that's hopeful, and that has gone off to the vet for a faecal parasite smear. Still no word from the lab about the sputum culture (only been 6 weeks, not like it's life and death or anything), so I'm not trying any more meds until we have something resembling a firm diagnosis.
I feel so bad for him, he's just weak and lethargic, and my hopes are fading again - but he hasn't seemed to be in respiratory distress now since mid January, and he hasn't lost a great deal more weight, so m-a-y-b-e the RI is gone and now it's just the loss of appetite due to the antibiotics.
Come on Nutribac, do your stuff!