Dominance

[s.s]

I have had my 2 male pigs for about 4 or 5 months and they were a bonded pair at the shelter. Ever since I brought them home one of them, Rusty, has been mounting my other one, Hugo, and chases him. Rusty was also mounting him at the shelter. Hugo rumblesruts and chatters at Rusty.

This always happens, at least while I'm in the room, and I've been separating them at night, but there's only one proper cage. I'm not sure what to do about this so I would appreciate any advice, thanks!

 

[fluffysal]

Every morning is a new bonding session to them because you keep separating them at night. You need to keep them together so they can establish the hierarchy then they will settle. This takes about two weeks.
If you look through the guinea pig info section there are fantastic guides to all of their behaviours. Unfortunately I am too much of a dinosaur to link them for you.
How big is their cage? Boars need more space than sows. There are also guides to recommend cage sizes.
Hopefully you can get them settled, a pair of bonded boars are delightful to live with especially when they get older.

 

[Piggies&buns]

Welcome to the forum.

How old are they?

Mounting and chasing is a mild dominance behaviour. It is something they will always do to reinforce their bond and relationship throughout life.
You don’t need to do anything about it because it’s a natural way that piggies communicate with each other about hierarchy. You should never separate them because of it.

You are likely to actually be making things worse between them by separating them as they will then show more dominance to try to reaffirm then relationship every morning when you put them back together. At worst, constant separation and reintroduction could actually ruin their bond.
Also, it is very stressful for them to be separated from their partner.
Equally, if you only have one cage the chances are that by separating them that they are then going into a space which doesn’t give them enough room so will cause further stress.

The only time you ever separate boars is if there is a full on blood drawing fight. Otherwise they need to remain together at all times.

Ensure their cage is ideally 180x60cm (or a 5x2 c&c grid cage) but an absolute minimum of 150x60cm (or a 2x4 c&c cage) but do note that the minimum is often too small for boars particularly if they are teenagers (between 4 and 14 months of age).
You also need to ensure that there is two of everything on the cage and that all the hides have two exits. Any dead ends can be a flash point for issues.

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

 

[s.s]

Welcome to the forum.

How old are they?

Mounting and chasing is a mild dominance behaviour. It is something they will always do to reinforce their bond and relationship throughout life.
You don’t need to do anything about it because it’s a natural way that piggies communicate with each other about hierarchy. You should never separate them because of it.

You are likely to actually be making things worse between them by separating them as they will then show more dominance to try to reaffirm then relationship every morning when you put them back together. At worst, constant separation and reintroduction could actually ruin their bond.
Also, it is very stressful for them to be separated from their partner.
Equally, if you only have one cage the chances are that by separating them that they are then going into a space which doesn’t give them enough room so will cause further stress.

The only time you ever separate boars is if there is a full on blood drawing fight. Otherwise they need to remain together at all times.

Ensure their cage is ideally 180x60cm (or a 5x2 c&c grid cage) but an absolute minimum of 150x60cm (or a 2x4 c&c cage) but do note that the minimum is often too small for boars particularly if they are teenagers (between 4 and 14 months of age).
You also need to ensure that there is two of everything on the cage and that all the hides have two exits. Any dead ends can be a flash point for issues.

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

Thank you so much, they are around 1 1/2 and right now they have a 3x2 cage because I just moved, but when I set up their old cage again it will be 5x5.
Thank you again for the information!

 

[Piggies&buns]

Ok. They are only just out of their teens then.

So I can see that there are two issues which will likely be causing this behaviour.

1. The move. Changing environment and territory will cause them to reestablish their relationship. That takes around two weeks. It happens every time there is a territory change - for some boars simply cleaning out the cage can set them off.
2. combining the need to reestablish with the fact their cage doesn’t meet minimum requirements will leave them feeling lacking in territory, and not enough room to get away from each other while restablishing their relationship. A bit of a double whammy there.

When you move them back to their 5x5 cage it will cause another round of two weeks of increased dominance as it is another change of territory.
You can try to mitigate the effects of it by making sure you use soiled bedding in the new cage so to transfer scents and help them recognise it.

Another guide below will also help you

Reacting to group or territorial changes: Dominance and group establishment/re-establishment

 

[fluffysal]

I can only agree with all of the above. I moved house recently with a pair of well bonded boars and it did affect their behaviour. I made sure I kept some slightly soiled fleeces so it wasn't too bad.