Introducing a new pig to an older one

Question
We were given a guinea pig about a year ago.  We think that she was about 6 months old then.  My daughter decided a week ago to buy another one to be a companion to the first.  This one is quite a bit smaller than the first and the pet store said that it was a "baby".  We have tried introducing them on neutral territory.  After a few visits they seemed to be okay w/each other.  However every time we put the baby in the cage of the other one the older knashes it's teeth and chases her.(By the way, both are female) This has gone on several times a day for three or four days- are we making progress?  And also, how big should the cage be if two are in it?

Answer
Hi Elizabeth

Two females will normally get along fine regardless of when the 2nd was introduced. The behaviour you describe is part of a process whereby the older pig establishes herself as the dominant one. If the behaviour turns into any sort of fighting, you must separate them, otherwise you should find that things settle down within a week or so. Let me know if you have any further problems.

The cage should be approximately 1 1/2 metres long to enable two pigs to live comfortably.

Andy