How to tell age of a abby from a petshop?

Question
My wife and me loved our first two cavies, we got them at a superstore pet store but don't know they're age. Is there any way to tell, the people there didn't know and didn't even know the sexes. For males and females? Thankyou from chip,skip,cocoa,Abby and us.  

Answer
Trevor,

Pet stores are notorious for sending home two "same sex" Guinea Pigs that are anything but, so check yourself or have a vet check your pigs for you. Here is a link to a site http://www.guinealynx.com/sexing.html this site will show you how to easily tell the sex of the Guinea Pigs.

As for age, there really isn't any sure fire way to tell it unfortunately. But most pet stores sell Guinea Pigs between the ages of 4 weeks to a year old. Size is a good way to tell, Guinea Pigs 4 weeks to about 4 months old are small to medium in length. Guinea Pig a year old or more are already fully grown. Which is anywhere from 10 inches to 15 inches in length. Unfortunately there really isn't a sure way to tell the age of a Guinea Pig. Though you may try asking a specialized small animals vet how to tell the age, they may know something that I don't. :)

Hope this helped a little bit at least. Take care now,
                            Jules