Horse aggressive to other horses - one in particular

[Alterration]

We have a horse here who is “top dog”. Most horses after a few rounds of kick-fighting and posturing, things settle and they just get out of his way. I keep him with the more assertive geldings, and that seems to be fine, although occasionally someone comes in with a bite mark.

Today when he went out he seemed a bit more aggressive than normal to his paddock buddies but they were in yesterday due to rain, so I didn’t think too much of it.

However, after a few hours of turnout, he got a gate off it’s hinges and attacked a mare like I’ve never seen a horse do in domesticity. He had chased her (I was trying to get other horses out of the way in order to grab him because everyone was then wound up) until he caught her and then he grabbed the top of her neck at her withers and was not letting go. She was screaming and trying to get away, and I managed to swing a rope at his butt and get him eventually to let go. He then went over to the other side of the paddock, let me catch him, and then calmly led in.

Thankfully, the mare is just scraped up, but…yikes.

She’s actually the reason he got separated from that herd in the first place, after he went at her with the mixed herd. It’s generally a peaceable herd, but she is low low low low man. She is an older mare, gray, and has some melanoma, so I am wondering maybe if she smells different or if she’s just the only one he can catch.

Obviously, they can’t share a fenceline again (the gate came off it’s hinges somehow, and that’s how he got through). He’s a big middle-aged solid healthy horse, eats a diet of some alfalfa and unlimited grass hay, lots of turnout until today.

Any ideas are welcome.

[Xanthoria]

It’s quite shocking when you see that level of aggression, I agree. I don’t want to say “victim blaming” but it really sounds like the gelding is the problem, not the mare. She is not the reason he was separated - she hasn’t done anything wrong, correct? He attacked her?

That type of horse gets invited to leave most barns I have been at.

[jmkos]

So my vet has seen amped aggression in certain geldings at a certain age in their life. She likened it to a gelding menapose…hormonal imbalances, where a normally fine guy gets very aggressive, one bit her in the shoulder and left a very nasty bruise. She treated him with something that she uses for Cushing horses and he calmed WAY down. Maybe speak with your vet if they are in tune with older/metabolic issues in horses. He was a good guy and then started bullying his pen mates, other geldings he had been friendly with for years. One day he just went after her. She’s an extremely accomplished vet and horseman.

[Alterration]

I’m the one who owns the barn. Most of the horses belong to me, but the mare does not.

The gelding is definitely the problem, but I am curious as to why he has chosen her for death. It’s an unusual situation - just not something I’ve ever quite seen before.

[Xanthoria]

I’ve seen one horse get picked on before (interestingly it was an older gray gelding) I’d agree with the other poster above who says she’s probably the only one he could catch.

I’ve also known three geldings over the years who were dangerous in turnout - to other horses but also humans. One was kept in a stall after it killed another horse, one was shipped off to parts unknown after it severely attacked my older horse (and the vet recommended euthanasia) and two humans, and the third is separated in another pasture.

[Alterration]

Good thoughts - I will check in with the vet for sure.

He’s generally a sweet guy to people, a little pushy, but nothing horrible. Certainly no attempts to bite or kick any humans. Calm under saddle, calm to handle.

I think I’m still in a little shock.

[candyappy]

@Alterration

The gelding is definitely the problem, but I am curious as to why he has chosen her for death. It’s an unusual situation - just not something I’ve ever quite seen before.

It is very common in my goat herd for them to single out any herd member who shows signs of weakness ( due to illness… etc) It can be quite shocking to see how brutal they can become and the does are normally very mild mannered.

It must have something to do with putting the herd at risk. I have no doubt that animals suffering from disease or debilitating illnesses are something the leaders can sense or even smell. Our domestic animals still have the instincts no matter how they are kept.

That poor mare. Can you put her farther away from the gelding?

[Alterration]

Right now they are going to have to go on “opposing” turnouts (night vs. day). I did have them separated by two fences, but unfortunately with the 11" of rain we got in one day the turnout the gelding was in is waterlogged (hence the abnormal fenceline sharing).

I’ve seen it in chickens, but chickens are little dinosaurs anyway!

Guess we know why this guy was cheap!

[Alterration]

I had a gray gelding get picked on before as well, and run through a fence by two other horses, so I do have a sneaking suspicion that color has something to do with it.

Overall I’m still coming down from the panic - had horses everywhere, me of course in my flip flops because I wasn’t planning to touch the horses (I was just outside checking water) and no time to change shoes. Dealing with wound up horses in flip flops and mud while one tries to kill the other one is kind of a nightmare!

[luvmyhackney]

This. I’ve seen it in my own herd of three when my ponies feet hurt.

They are a-holes to him. When he feels fine they scratch him and get along fine.

[Alterration]

It is possible then that they (or he) knows she’s weak.

She has cushings, melanomas, and she’s a gray. No idea on the state of her feet (she’s not mine). I just feel so awful for her. She’s super bonded with a young horse of mine, which is good, but that causes other issues because he’s a fence jumper, so I have to keep them together and paddocks are limited because we have boarders coming in that can’t maneuver around him (young horse).

[NaturallyHappy]

I’ve had it happen twice in 30+ years; it is really frightening. One was a gelding who went after another older gelding, and the other was a very nasty mare who went after a mild mannered mare about the same age. We separated the geldings. The person who owned the nasty mare left when I said her horse had to go alone.

[Bluey]

Some years ago we bought a five year old gelding.
We kept him across the other four geldings and all seemed to be getting along fine, no faces or fighting at all.
After some days fed in the big pen, about ten flakes of alfalfa spread out, the four were eating and I let the new horse in there.
He went to one flake and started eating and then out of the blue he ran at the meekest horse, across the large lot and attacked him, mouth open, grabbed him by the neck above the withers and knocked him down and without letting go got on top of him with his knees while shaking him.
I still had my manure cart with feed rubber bucket I had been putting hay out and threw the rubber bucket at him as I was running at him swinging the manure cart.
As I got there he left that gelding and ran off a ways, I got him penned and tended to poor gelding, that was still shook, but seemed not hurt, just a few bite marks on his neck.

A neighbor had seen that pretty new gelding and asked about him, I called, explained and he said he had some real rank older ranch geldings that would teach him a few lessons, bring him by.
Later he wanted to buy him, he was getting along ok, other than he had a few bites he received by the boss and his teenage son really liked him.

That is the only time from many horses we have introduced that caused any aggression problems. Generally is the other way around, across a fence some show a bit of barrier aggression, nothing serious, faces mostly, but once with the herd, they all get along fine.

If you ever see a horse really attack another, it does make an impression, sorry that happened to you.
Since we don’t know why that happened, there was nothing we could tell wrong with the meek gelding, a ten year old, that is now still in his late 20s giving lead rides to little kids, is best to not go there again and let them anywhere close to each other.

[Alterration]

I’m glad to know that it is rare. I’ve been in horses for 36 years now and this is a first. I think I’ve been lucky.

The screams were awful. Poor mare was so scared that she urinated all over as he had her. She seems ok tonight, but I’m sure she will be looking over her shoulder for awhile.

[Alterration]

Oh they are definitely never sharing a fenceline again. That was horrifying.

I’ve seen a lot of scuffles that make one cringe, but this was so much worse. I’m just super glad I was home and came out to check water, in hindsight.

[AnastasiaBeaverhousen]

A former instructor had a gelding that suddenly started attacking his gelding pasture mates for no reason.

It turned out he had too much testosterone. He was put on meds and he was able to go back out with his pasture mates after the meds kicked in.

So I’d start there.

[Djones]

I had a gelding who never did settle here in a set of 4 geldings total and a gelded jack. He was pushy and picked on my best horse and at some point, put the best horse over a fence. He was lucky I didn’t shoot him dead, I thought about it. I sold him and he’s now in a good situation with a very dominant gelding who put him in his place.

Your gelding is an asshat. I’d keep him alone.

[walktrot]

I’ve seen two problems in 20 years. My gelding was on psture board. He was alpha for the entire 20 years he was in that field. He was never challenged. There was a core group of lesson horses and usually a few other boarders who were stalled overnight. A new horse would come in from time to time but there wasn’t much commotion. My gelding used a flip of a nose usually with pinned ears, sometimes showing his incisors. On the whole he didn’t have to do much work unless someone dawdled. New horses settled in with few problems.

The first one who didn’t fit in came with a new instructor. The first time he was turned out with the geldings they ran him out of there in less than 30 minutes. He went to a round pen for a week or so. Same problem when they moved him back to the geldings. He was okay by himself, but the owner wanted him out with other horses. The one thing she neglected to tell the barn owner was the testicle somewhere in his abdominal cavity. He was a cryptorchid. He needed major surgery to locate and remove it. She didn’t want to bother about it now even though she could afford it.

The second problem was a new big black gelding. He was described by everyone as mean and nasty. Kids were’t allowed to get their horses. Adults were scared. He ran all the geldings off the waterers, round bales, if they were napping, and he would keep at it. He frequently started from behind a shedm emerging at a full gallop. BO wasn’t paying enough attention. Having known her for 20 years I was the chosen one to email her. BO’s response was a plan to move him somewhere. When I moved to another barn a couple of months later he was still there.

A lot of people chalk up this kind of behavior to the pecking order. It isn’t. That gelding is in attack mode and he isn’t interested in finding a spot in the pecking order. The cryprtorchid had a similar problem driven by hormones and the horse owner’s unwillingness to admit she owns a stallion.

[prunebey]

I have a mare who is basically word for word how you describe the mare he attacked - old, gray, melanoma, Cushings, and the lowest of the low in the herd. I’ve watched her be chased repeatedly and attacked once to the point of drawing blood…for seemingly no reason other than existing. It’s honestly really interesting to hear that multiple others have seen grays in particular get singled out by bullies.

[Bluey]

@Alterration

We have a horse here who is “top dog”. Most horses after a few rounds of kick-fighting and posturing, things settle and they just get out of his way. I keep him with the more assertive geldings, and that seems to be fine, although occasionally someone comes in with a bite mark.

Today when he went out he seemed a bit more aggressive than normal to his paddock buddies but they were in yesterday due to rain, so I didn’t think too much of it.

However, after a few hours of turnout, he got a gate off it’s hinges and attacked a mare like I’ve never seen a horse do in domesticity. He had chased her (I was trying to get other horses out of the way in order to grab him because everyone was then wound up) until he caught her and then he grabbed the top of her neck at her withers and was not letting go. She was screaming and trying to get away, and I managed to swing a rope at his butt and get him eventually to let go. He then went over to the other side of the paddock, let me catch him, and then calmly led in.

Thankfully, the mare is just scraped up, but…yikes.

She’s actually the reason he got separated from that herd in the first place, after he went at her with the mixed herd. It’s generally a peaceable herd, but she is low low low low man. She is an older mare, gray, and has some melanoma, so I am wondering maybe if she smells different or if she’s just the only one he can catch.

Obviously, they can’t share a fenceline again (the gate came off it’s hinges somehow, and that’s how he got through). He’s a big middle-aged solid healthy horse, eats a diet of some alfalfa and unlimited grass hay, lots of turnout until today.

Any ideas are welcome.

Our meek, quiet, sweet horse was liked by all and sorrel.
In our situation, I think his low end status is maybe why he was the target, was nothing wrong with him.

Not all over the top attacks may have the same reasons behind them.