Continious vibrating noise

Question
Hi,

I had my first guinea pig (male) 7 - 8 months now and I just got another one three days ago because he seemed lonely. My new guinea pig is just 8 weeks old. I'm not sure what sex it is because I know you have to wait until they get older. At first, I kept them in seperate cages but close enough so they could get to know each other through their bars. On the second day, they kept crying and biting the cage bars like they wanted to be with each other.

I was super paranoid because I didn't want my older one to attack the younger one! But I just couldn't handle the high pitch squeaking anymore. So I decided to put the younger one inside with my older one.

They are getting along just fine with no biting involved. I sat there for almost an hour just watching to see if any type of fighting was going to happen. They play, chase, share food with no problem. But my older one keeps making this continious vibrating noise, it sort of sounds like the "mating" noise. He also smells the younger one's butt a lot.

What does that mean? Is it normal? Or do I have to be concerned?

Answer
Hi Chanel

Firstly, you can determine the sex of your younger pig straight away, there no is no to wait. Take a look at the link below and also, if you gently press its tummy, a little penis will pop out if its a boy.

Presuming the younget pig is a boy, the behaviour is normal, the older one is "checking him out" and establishing dominance over the younger one.

Andy

http://www.diddly-di.fsnet.co.uk/Sexing-Guinea-Pig.htm