Guinea Pig behavior & food

Question
Hi Andy.
We bought our first guinea pig last November when he was 7 weeks old.  He is kept indoors as we live in a flat but he has a decent sized cage.
Firstly - he is jumping around what we think is unnatural like he is having a fit or something. He does this quite a lot. sommersaults and flips etc. is this normal?
Secondly, although we have tried him on virtually all fruit including tomatoes, apple, orangles & carrots he will only eat lettuce and cucumber, the latter being his uttermost favourite and he would eat that constantly if he had the chance.  He adores his Blueberry Guinea food that we buy him but he only eats the grass bits from that and leaves the rest.
A little concerned about him as most of the books we read have conflicting data.
Please advise. thank you

Answer
Hi Mark

Firstly, the having a fit thing is called "popcorning" and is a guinea pigs way of showing he is enjoying himself.

Your pig sounds like a very fussy eater. You need to be careful how much lettuce and cucumber you give him as it has no nutritional content and can cause diorreah in large doses.

Perhaps you need to try a different brand of dry food if he doesnt eat much of it. However, my experience is that if you leave the unwanted bits in the bowl instead of topping up with his favourite bits he will eat them when he becomes hungry.

Hope that helps but feel free to write back if I can assist you any further.

Andy