Horse suddenly bullying field mate at the gate

[AAHorse]

Hi,

Just wondering if anyone has any ideas why my horse has suddenly become aggressive with another horse at the gate at bring in time?

There’s never really been an obvious herd ranking up until now and she’s always been a really sociable, friendly horse with others, and in particular has been inseparable from this one mare. Over the last couple of weeks though, she’s been getting aggressive with this horse at the gate (biting, threatening to kick her) and I have no idea what’s causing it - seems to have come out of the blue. They’ve been getting brought in together through winter but it’s only become a problem the last couple of weeks, but not every day.

Grass has started to grow so she’s never waiting to come in when I go to get them (so isn’t desperate to come in because she’s hungry), and she’s getting plenty of turnout/exercise. The whole herd happily grazes together during the day, it’s just every few days at bring in.

Any ideas on what could be causing this, and any advice on how to deal with it until they can all stay out 24/7 and come in separately? Thanks

 

[ycbm]

If you copy this to Tack Room you'll get more replies. I would guess this is hormonal, how long have you owned her?
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[AAHorse]

If you copy this to Tack Room you'll get more replies. I would guess this is hormonal, how long have you owned her?
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Thank you, reposted there now! Had her about 9 months, she was pretty bad with her hormones last summer but never took it out on other horses so it’s a bit out of character, hormones do make sense though

 

[ycbm]

First one of the year is often worst, and this is the first one you've owned her with. Hopefully she'll be back to normal soon.
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