Why is one of my guinea pigs so fat and the other so thin?

[HerMajestiesSecretCervix]

They are supposed to be brothers, they are kept in an identical fashion but they are so different. One is a big dope and the other a skinny little live wire. Should I try and reduce the ad lib food and give skinny pig separate access to food? Any advice appreciated.

The fat one will be the dominant one. Two bowls of food usually works.

I thought that too but fattypig is the humpee and skinnypig the humper.

I will try 2 bowls - thanks for the tip!

My rats are like that too. One skinny and the other a big fatso!

They seem happy together though so I don't really worry.

....they're definitely both boys right?

the skinny live wire calmed down and got just as fat and lazy I'm afraid in our case.

we have two girls. One was calm prettym uch from the beginning, would settle on your lap peacefully and the other was a nut-job, charging about frantically all the time ad drinking a lot but not eating so much.

The live wire changed. He he at folk, have you checked OP?

FAt one is the calm sub-dominant one in the pair I look after. Skinny one is horrid bossy boots.
Are you sure they are both boys?

Well, it did cross my mind that they might not both be boys but we've checked and they both have the same looking bits so they are the same sex. If we get a surprise delivery of baby guinea pigs I will not be impressed but DD will be ecstatic.

They are such different characters too - I'd forgotten how charming guinea pigs are.

Hummm... you might want to get a friend to sex them; you press on the tummy & out pops the willy. No willy = girl. There is no other reliable method, imho. With mature males you can often feel the testicles, but not consistently.

If it is a pg female you'd probably be able to feel the babies inside; they get HUGE before giving birth.