Is it possible to bond two guinea pigs that have lived separately in neighboring cages for a year?

[charbo]

This is genuinely a question born out of curiosity rather than intention.

I have two boars who have lived next to each other in separate C&Cs since last February. At four months old, we moved them from their shared WAY TOO SMALL cage into a 2x6 and they immediately had a fight. We separated them immediately because we couldn’t tell if there had been biting or if one of them had gotten scraped on a grid. They’ve lived side by side in 2x4s ever since.

I was thinking today as I was sweeping kicked up hay and poop: could they ever be friends? They mirror each other’s behavior all the time, they definitely have some cross-contamination of smells and debris (sometimes cage accessories too, if I’m honest), and they literally spend all of their time together. I’m probably never going to attempt to re-cohabitate them, but it got me wondering if having that barrier between them for so long had any effect on their bonding potential; if they were to be suddenly reintroduced into each other’s physical space would they be more or less likely to fight than if, say, they’d never met? Or were separated after failing to bond?

 

[Piggies&buns]

Living side by side does not mean a bonding is any more or less likely to be successful.
The success of a bond still comes down to character compatibility - they either have it or they don’t. Two piggies can just meet, live side by side for a day or for a year but the bonding still fail upon introduction due to character incompatibilities.
Living side by side for a few days prior to attempting a bonding can be beneficial in that they can get used to each other first and is a recommended step to take prior to bonding two unknown piggies. As I say though, it won’t make the chances of success any greater.

If two piggies were brought into a home separately, put straight into side by side cages but an introduction had never attempted for no matter the length of them they’ve lived side by side , then a future bonding may be possible.
It might work, it might not. it’s always a case of you have to try it to know.

Where two piggies had a failed attempt at bonding first time or who used to be together but had a fight, the situation is different.
They cant be reintroduced. No amount of living side by side will fix it - they won’t change their minds about each other and if reintroduction was attempted, further fights would occur due to the character incompatibilities that will still be there.

Behaviours you see between the bars in this scenario while it is an interaction, it is also territorial behaviour. Laying against a divider etc is not a sign they want to be together and is simply a territory patrolling exercise.