Hi Emma, I have never had to care for a baby kitten like yours, but quite a few others here at TDK have done. I would suspect that most vets know a lot about illness and injury in animals but, like me, have never been involved in the day to day care of normal, healthy but orphaned or abandoned kittens. In which case, I would be happier following the advice of those who have actually done the job many times over.
Since I’ve been a member here I have lost count of the times I’ve seen worried foster parents of kittens asking advice about feeding because the baby has constipation or diarrhoea. Each time they are told that goat’s milk is better for them than the formula kind, which often produces those worrying symptoms in the kittens. Sometimes the advice is taken – and the kittens thrive on it. Their tummies become more settled, they become happier, they’re not always crying because they’re hungry.
If it’s at all possible for you to get hold of some goat’s milk, even just some to try for a couple of days, that would be my advice. As I said, I have never been in your position – I’m not recommending from my own experience. But it seems to work for so many others, so I honestly think it’s worth a try.
These links are often suggested as a help to people rearing kittens – you could take a look at them too, for hints and tips with all sorts of things you’ll come up against.
– http://messybeast.com/handrear.htm
– http://www.safehavenforcats.com/newborn.htm
– http://dailykitten.com/chat/topic/helping-a-kitten-to-eliminate/
Best of luck with your baby – you say he’s happy, which is a good start!