aggressive male

Question
Hi, I started off with three guinea pigs last year. All were female. Two of them we discovered to be pregnant. When the babies were born, one was female, the other was a male. We decided to keep them both and have the male castrated.
The male is nearly a year old and has become very aggressive to one of the females (the one that wasn't pregnant). The male chases her and nips her on her hind qaurters drawing blood. Is this normal behaviour and if not is there anything we can do to stop this. He isn't aggressive to the other females only this particular one.
Thanks in advance.

Rebecca

Answer
Hi Rebecca,

I suggest you have a quick check between the hind legs to make sure this one is actually a female! It's very unusual for a male (especially a neutered one) to bully a female - it is highly possible that she's actually a male and they're fighting for dominance. If so, you will not be able to keep them all together.

It could also be that she is the "alpha female" which sometimes happens, and that the male is fighting with her for the same reasons. Either way, once blood has been drawn it is unlikely that the two piggies will ever live together peacefully and you will be best to split your group and keep the male with one of the females he's nice to, and the other three females together.

Hope this helps.

Jenny.