Guinea pig suddenly attacking the other.

[Kirbs]

We bought two male 8 month old pigs around two months ago as they were adoption ones in Pets At Home. Up until now they’ve been fine; cuddling and playing. Yesterday morning we woke up to find one (Blueberry) hiding in the hay rack away from the other (Mr Muffin). I took him out to find out his coat had blood on it (he’s white so it’s easy to tell). He’d been bruised on his back along with scratch marks and bites (I think they’re bites), there was also one a bit away from his head. We separated them by blocking the stairs but by this morning they were together in the bottom but Blueberry had jumped in the hay rack. I took him out and put him back in while I made a better barrier thing and they were fine for a few seconds but Mr Muffin was chasing Blueberry until he hid (Blueberry didn’t fight back). I have separated them again now so they can’t get past it and be hurt further. Mr Muffin has previously fought with our other guinea pigs who are in separate cages and is the dominant one. Any idea why he has suddenly attacked Blueberry?

 

[Swissgreys]

Sorry to hear that your boys aren't getting on.
The reason for their sudden fall out is most likely teenage hormones which will be ramping up at this age.

A good place to start to work out what is going on with them is here:
Boars: Teenage, Bullying, Fighting, Fall-outs And What Next?

Sadly once they have had a fight and blood has been drawn it is unlikely they will be able to love together again, so it might be time to consider a set up that at least allows them safe contact through the bars, but without being able to hurt each otehr.

 

[Wiebke]

Hi and welcome!

I am very sorry that your boys are not personality matched. Sadly that key aspect for any successful piggy bond is generally not one that comes up when choosing pet shop babies.

I fully agree with @Swissgreys ' advice.