18 month old guinea pigs

Gp minder

New Born Pup
Sep 1, 2020
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Burton on trent
Just before lock down I had to house two gps and as it was originally only for two weeks and due to other circumstances I had to get a small hutch. They were fine in the shed until it started to get warm. C bit S - I thought due to lack of space - trip to vet etc. I bought a big two storey hutch and thet seemed fine again. C definitely the dominant one. Now S is mounting C all the time and driving him mad. Loud teeth chattering and running around hutch. If I seperate the but they can see each other they are desperately trying to get to each other. Then the mounting starts again with sone lunges. No biting as yet. They are eating grass in a run Together as I type and appear ok for now. My conern is that they are shortly going back home To working parents who wont have tme to let them out in the garden each day How much squabbling before they need permanent separation?


Forum Donator 2020/21
Aug 2, 2018
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Changing location can cause them to re-establish their hierarchy. If the submissive then tries to take over dominance then it can cause problems. Hormones spikes will also cause an increase in dominance, but on its own mounting, chasing, rumbling are all normal dominance behaviours and are not a reason to separate.
You only separate if they have a full on blood drawing fight, the relationship is clearly dysfunctional or if clear signs of bullying occur (the submissive pig is never allowed to eat or rest, loses weight and is generally depressed, or fights back and such a blood drawing fight occurs). Sometimes small defensive nips can occur, often if a piggy is cornered in a hideys (which is why all hideys should have two exits and not be enclosed).
If a serious fight and injuries has occurred then they need separating permanently
If you do separate to give them time to calm down, then any reintroduction need to be done on neutral territory. You can only separate a limited amount of times though before it causes a problem. You will always see dominance upon reintroduction.
Two boars need a cage of 6ft x 2ft (on a single level, upper levels don’t count towards the cage size) so being kept in anything less can cause tensions.

A Comprehensive Guide to Guinea Pig Boars
Dominance Behaviours In Guinea Pigs
Boars: Teenage, Bullying, Fighting, Fall-outs And What Next?
Bonds In Trouble
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