
Hi Colin. There are several causes of fits, some of which are curable and some of which aren't, I'm afraid. The blood tests will help to narrow down the possible causes, but it may be that he as what's called 'idiopathic epilepsy' - ie there is no known cause. He's slightly on the old side to develop this (18 months to 4 years is the most common) but it's not impossible. Please let his breeder know because if he does have epilepsy he shouldn't be bred from, and the breeder shouldn't repeat the mating that produced the litter he was in.
Try not to worry too much. He may not need much if any medication to control the fits and is likely to still have a long happy life.