A after a very bad few hours, this evening we took brandy to another vet, who did not think an x-ray/scan was necessary. He ran another blood test and once again it came out pretty normal.
This vet is also baffled.
He thinks that whatever brandy has is likely to be degenerative, but wants to eliminate possibilities. He therefore gave him a steroid injection and I have another appointment tomorrow evening.
Brandy had a great appetite this evening, he is moving around a bit and is also alert. So the steroids have made some sort of effect.
Fingers crossed he'll also be fine tomorrow, perhaps that will indicate possible causes and some hope for Brandy.