Sow In Heat..?

[Beans&Toast]

So I've had Beans and Toast for about a year now. Beans seems to be the domanent one, although most of the time they get on absolutely fine. When it comes to being in heat, Toast can get a bit agressive and relentless with her chasing Beans around, but no violence or anything. However, lately when Toast is in heat, she seems to be getting more agressive with Beans, nibbling her ear, being very forceful trying to mount her, and making a very loud vibrating sound whilst strutting around Beans.
Does anyone have any ideas as to why Toast's behaviour has got more forceful lately?
Apart from while in heat, they get along just fine, even licking each others eyes and grooming each other

 

[Wiebke]

So I've had Beans and Toast for about a year now. Beans seems to be the domanent one, although most of the time they get on absolutely fine. When it comes to being in heat, Toast can get a bit agressive and relentless with her chasing Beans around, but no violence or anything. However, lately when Toast is in heat, she seems to be getting more agressive with Beans, nibbling her ear, being very forceful trying to mount her, and making a very loud vibrating sound whilst strutting around Beans.
Does anyone have any ideas as to why Toast's behaviour has got more forceful lately?
Apart from while in heat, they get along just fine, even licking each others eyes and grooming each other

Adult sows can experience hormonal issues. Ovarian cysts can start developing from about 18 months onwards at the very earliest. it is usually when the very small ones grow a bit that you experience aggressive behaviour, which is usually worst when sows are in season. the really large cysts are often not causing any visible or behavioural problems. They are pretty common in older sows and most don;t need treatment.

Yours are still in the very mildest range. As long as it is not really disruptive for the bond, I would not fret and just leave be - your girls are still reaffirming their bond with exchanging affectionate behaviours afterwards. It is likley to abate again when the cyst stops growing.
If things get really bad, you may want to look into hormone injections, but as they can come with side effects, you do not want to jump in too early.

 

[Beans&Toast]

I had them at the vets a couple weeks ago for a check up and they were checked for lumps and bumps and the vet said all was fine. But is it possible they could have lumps that were missed?
As for their bond, they get along well most of the time. They don't bite or act aggressively to each other apart from the times when in season, and even then it's never been a full on fight, just nibbling and strutting around each other. Sometimes it seems as if they are both trying to be the domanent one, and from watching them it seems like it's Beans, but Toast keeps trying..

I rescued them from an adoption centre, they were not originally together from birth, I introduced them at around 2 years old and they've been together for around a year now- can it take this long to sort out who's in charge?

 

[Wiebke]

I had them at the vets a couple weeks ago for a check up and they were checked for lumps and bumps and the vet said all was fine. But is it possible they could have lumps that were missed?
As for their bond, they get along well most of the time. They don't bite or act aggressively to each other apart from the times when in season, and even then it's never been a full on fight, just nibbling and strutting around each other. Sometimes it seems as if they are both trying to be the domanent one, and from watching them it seems like it's Beans, but Toast keeps trying..

I rescued them from an adoption centre, they were not originally together from birth, I introduced them at around 2 years old and they've been together for around a year now- can it take this long to sort out who's in charge?

The ovarian cysts that cause the problems are usually too small to be noticeable, as I have tried to explain to you.

At that age, the change is usually due to a cyst; dominance gets established right at the start and is later only relinquished due to illness etc. I have a whole raft of mildly hormonal sows here, right now! Most settle down again after a few weeks, none the worse. Unless things get a lot worse and you see some really aggressive chasing/mounting on a daily basis with other sow coming to the end of tether, I would not yet worry.

 

[Beans&Toast]

Thanks for the advice much appreciated