My gelding suffers from PMS.
I rode today with two friends and two family members... the two friends came over wanting to ride because they're younger (9 and 12) and didn't have anything to do. My cousins (10 and 13) got permission to ride from their mum and dad... so we set off.
I rode my gelding.
My eldest cousin rode her mothers mare.
Her younger sister rode my friends brothers mare.
My two friends doubled up on my mare.
And my gelding decided to act like a 'Pissy Mare'.
It's not really an unusual problem... he's always been just fine riding with my mare (his dam) but with any other horse, even his pasture-mates, he gets... well... pissy... aggressive... and attempts to kick and bite and pins his ears badly when one of the other horses besides my mare comes near him. Because of this, I really don't like riding him in groups... though he's gotten much better lately. Used to, he would act aggressive towards his other pasture-mates, but recently it's stopped and he's stopped acting aggressive towards my other friends horses...
We've ridden with my friends brothers mare a few times now, and he's always been fairly well behaving... a little ear-pinning, but not to the extreme he was doing today.
Today, he was just fine with my cousins mothers mare and my mare, but nearly every time the other mare inched anywhere near to him, his ears pinned and his head arched and he would act like he was going to try and turn his butt to kick or he's try to bite... and not just nips... he was going all out.
When we would trot or canter, he was fine... but at a walk, he acted like... well, it's just hard to describe...
I don't understand it... he's been fine with this mare the other few times she's been ridden... except for a few ear-pinnings... but I get after him good for stuff like that. He's knows what he's doing is wrong, yet he still does it.
When we ride in groups, I feel like I need to keep him at the back for safety reasons, but it's kinda hard when I've trained him to be a 'lead horse' and he thinks his place is at the front, or near the front. He listens well, but it's like he's just unhappy to be at the back... but with him at the front of a group, if the wrong horse gets behind him, he kicks.
My boy isn't the herd leader in the pasture... he's right below my mare, who is the 'second in command'... we have seven horses in the pasture, so he's right in the middle. His 'buddy' is my mare, yet neither of them are buddy or herd sour.
What can I do? I can't reprimand him for it when we're just leading the horses along, because then he's just fine and behaves perfectly. My neighbor, who has bred, raised, and trained horses for years said that it seems like my gelding is trying to 'protect' me, as he's watched the way he is... he said it looked like he didn't want any other horse besides my mare getting near me when I was on his back... but that can't fly, because I'm wanting to eventually ride in parades and stuff with my gelding, and I ride in groups of at least two or three 'strange horses' (horses my gelding isn't pastured with) about three times a month or so.
I didn't ride any differently today than we've been doing... nothing much was different... the 'strange' mare is in heat, and kept peeing all the time and winking, but she was doing that last time we rode and he didn't act this bad... He tried to kick once, but missed, and I got on to him really fiercely... but I was more concerned with his trying to bite, because, like I said, it wasn't just little nips... if he'd have got the other mare, he could have bitten through flesh and drawn blood... he was acting really aggressive towards her about half of the time... but not with the other two mares.