Is my Horsefield tortoise ill?

by Flo
(UK)

I'm worried that my Horsefield tortoise may be very ill. We have had him now for two years, he is around 10 years old (male).

Last summer he began to lose weight. After a trip to the vet we increased the heat in his vivarium and he seemed to perk up, however we did not hibernate him as he had lost too much weight. He had been eating and gaining weight but recently he has been totally off his food - he won't eat dandelions, cucumber or even the pellets that often get him eating again. He does hide in corners, try to bury himself etc. quite a bit, but becomes more active when we're there keeping him company, when he seems inquisitive and mostly full of energy - he enjoys trundling around the greenhouse. I haven't looked closely but his mouth seems nice and pink, no cuts or injuries immediately obvious, and we bath him regularly, sometimes with a glucose supplement... However he won't eat, no matter what we do, and is losing weight.

We have taken him to the vet and he has been wormed, but the situation has not improved. I'm wondering whether his behaviour could indicate that he is too cold, has an illness or maybe would cheer up if he had a mate. To my knowledge we feed him the right stuff, he is in a vivarium with compost and sand, with heat and UV lamps...I can't figure out what's wrong. Can anyone help?