Help!?

Question
I've had my two guinea pigs together for quite sometime now. I thought that they were both male. I've recently been noticing a change in behavior in one, named Sherman, what i thought to be a he. Sherman is not as friendly and seems to be more anti-social, when normally he just wanted to be with you all the time. I also noticed that he has gotten to be a little "wider" and has grown, I guess you would say, nipples on his underbelly. Now that i actually look I noticed that the "privates" are different between Sherman and Steve and I'm starting to think the Sherman is a pregnant female. How can I tell if it is pregnant? And how do I know if it's a female? What do I do if she is pregnant? Please help me!! Thank you so much!

Kailin

Answer
Here are some sexing guides: http://www.cavyspirit.com/sexing.htm
http://www.guinealynx.info/sexing.html

Male guinea pigs have nipples too.

Please read over: http://www.guinealynx.info/reproduction.html too

You need to separate them asap if they are a breeding pair. If she is pregnant and gives birth when she is still with the male, she will be backbred.

You should be able to feel the babies moving in the 6th week. A good exotics/cavy savy vet will be able to tell you for sure. You'll just have to wait and see unless you want to get an ultrasound.

Give her some alfalfa hay and alfalfa based pellets, and fresh veggies.