Rumbling is not fighting.
Rumbling is normal dominance behaviour and a way of maintaining their relationship for their whole lives but it is more prevalent during the teens. This is when a piggy is between 4 and 14 months of age.
So Simba around 8 months now and Mango is 4 months - is that right?
If so, right now Simba is coming up to another hormone spike and Mango is just starting in his teens and his hormones are rising. There is going to be a lot of testosterone flying around for the next months.
There is nothing you need to do about normal dominance though - you let them get on with it.
However, it is also important to check that you aren’t inadvertently causing it.
Things like disrespecting their hierarchy - handling the submissive piggy first will cause the dominant to feel the need to constantly reassert dominance.
Cleaning the cage too much can also cause it. If you remove all the soiled bedding in one go, then you wipe the cage of all scent and it will then cause them to need to reestablish their bond.
Make sure their cage is big enough - 180x60cm
Make sure all hides have two doors
Make sure there is multiple of all items
Dominance Behaviours In Guinea Pigs
Reacting to group or territorial changes: Dominance and group establishment/re-establishment
If however they aren’t compatible and it slips over into bullying then that is different. That is a sustained behaviour which is so relentless the submissive piggy becomes withdrawn and depressed. They may lose weight at each weekly weight check due to being chased away from hay. Bullying may also result in a full on fight where the submissive piggy finally has enough and is pushed too far.
If there is bullying or actual fight which causes injuries and draws blood, then their bond is over and they would need to be immediately and permanently separated.
Boars: Teenage, Bullying, Fighting, Fall-outs And What Next?
