not recovering from URI

Question
Scamper stopped eating on Thursday and Friday night we noticed he was wheezing and had gummy eyes. He was obviously very sick so we rushed him to the vet as soon as they opened. They gave him antibiotics for a URI, injected a water pouch to rehydrate him and cleaned about 3 days of poop from where he hadn't pushed it out.
It's now Tues. night and he's  still not eating. He's so weak he can barely lift his head. I bought Oxbow Critical Care but he can't seem to swallow it unless it's really watery and because he can only take a few sips every few hours I don't think it's helping. He gets so exhausted if I put the syringe behind his teeth and squirt a little into his mouth it just runs out the other side. I called the vet but they just want to do X-rays and expensive tests when it's obvious he needs food! Please, please help. We love our little scamp and he's only 2 1/2. Thank you.

Answer
Hi Merrilie

Sorry for the delay in my reply, my phone line was down.

I think all that may be needed is a different antibiotic. Baytrill is often used for piggies, was this the one the vet used?

Also, did the vet not suggest syringe feeding mashed up food?

andy