I have a 5 year old mare with puzzling behavior. This has happened 4 times in the past 3 months. She goes from perfectly calm and normal to crazy while in her stall. Just happened again tonight. She’s turned out 24/7. Brought her in to eat eat her grain (1 lb ration balancer, maybe 1/2 pound beet pulp, joint supplement, gut supplement, and some MSM. She ate her grain, then stood around waiting for her friend to finish her supper, then like a light, something switched on. She runs out of her stall and into the pasture about 100 mph, turns around runs back, sliding stop. Bucking, rearing, kicking. Runs into her stall and continues to rear and kick, buck. Does another lap in the pasture. I try to get to her and put on a halter to calm her down, and she won’t let me near. She’s violently thrashing around, kicking at imaginary threats, kicking the barn. After 3 minutes, she stops, walks up for me, and I can then pet her, rub all over her, and she is back to her calm self. Every time this happens, it’s almost as she got bit by something and throws a tantrum, but I’ve never seen anything around that would be biting (she is however very sensitive to bug bites). 3 out of 4 times this has happened have been after she finishes eating her supper at home. The other time this happened we were at a show and I was walking her down the barn aisle. She was perfectly fine one second (young kids were petting her, she was being walked by kids), then like a light flicked on, she lost her mind. Started rearing, bucking, and kicking out violently with both back legs. I quickly took her from the kids and she drug me down the barn aisle as she continues to kick, rear, and spin. I got her to her stall and quickly shut the door. She continues to double barrel kick the stall walls, then all the sudden snapped out of it, relaxed her head, and stood there calmly. What in the world could be causing this erratic behavior?
First, I’m sorry this is happening to your mare. Second - do not try to catch her/halter her when she is in this state of mind. You could be severely injured or killed, and that would not be good.
While I can’t say what is causing it, I’d start with a vet visit and pull blood to look for imbalances in her blood chemistry. I’d also have her tested for Lyme and possibly EPM. I think I’d stop using the MSM and other supplements for now (the one for ulcers though, I’d keep - unless there is some reason to suspect some odd reaction to it, then you might try something different).
Its entirely possible, since this happens after dinner most frequently, that something in her dinner is setting her off or aggravating her ulcers. I’d discuss that with the vet as a possibility and maybe discuss putting her on a single something - like grass or alfalfa pellets for a while to eliminate that as a possibility.
And because she is a mare, I’d have a reproductive checkup. Could be her cycles and her behavior are somehow linked.
Good luck to you and your mare.
Thanks for the response. Yes, I usually just try to keep everyone away from her when this is happening, but she was in danger of hurting herself tonight so I tried to intervene- but I stay on the other side of the fence.
I will try eliminating everything at supper but the ration balancer and Uckele GUT and see if the episodes stop. I did have her on a trial of Regumate for a month a few months ago but didn’t see any change in behavior. I also did a two month trial of omeprazole in case it was ulcer related. She was just checked out by the vet. Had some foot soreness he thinks might be related to improper angles in her trimming- but the way she runs around daily I’m having a hard time believing her feet are that sore. He suggested she was just the horse form of ADHD?? She used to be so calm- I know something is wrong I just can’t put my finger on it.
Sometimes its just a matter of eliminating things until you find the cause. That can take time, and a bit of patience.
Also, when were her teeth last checked? That’s another thing to take a look at.
Teeth were done 4 months ago.
Been around a long time and never seen teeth cause temporary self destructive berserk spells. Ulcers either.
How long have you had her? Has the vet pulled a blood panel? Has vet examined her ovaries and ultra sounded? Have seen ovarian cysts create impressively bad behavior. Unfortunately brain tumor as well.
In the meantime, I’d just block off her stall and keep her completely outside 24/7 before she kills or cripples herself. Or you.
I had a similar experience with a horse I was leasing - an older, seasoned FEI dressage gelding. He was a very calm guy, super safe, a perfect schoolmaster. But the last year I leased him, he would have these random episodes where he would be freaking out for no apparent reason. It was like he was terrified of something and he would start spinning, rearing and kicking in his stall. And then he would almost instantly go back to his normal calm self. It happened once at a horse show while he was resting back at the trailer. Unfortunately it turned out he had a brain tumor which led to him suddenly losing his ability to stand, and he had to be euthanized. It was so heartbreaking. I don’t know for sure if the tumor caused the erratic behavior, but he had no other known health issues.
I really hope that you are able to figure out why your mare is acting so strangely, and that it is something simple and fixable.
My thought was if she had a molar with an odd crease or divot or something, that perhaps a piece of a pellet/feed might get lodged in there, and cause temporary, intense pain. Not that I’ve ever seen that happen, but just thought a thorough dental exam would rule that out as a possibility.
I had an elderly mare who would have similar attacks, mostly blind running thru things than a sudden stop and return to her normal sweet self, occasionally she would show high levels of aggression to other animals - she was a grey with large numbers of melanomas so I tend to lean towards one of them impinging on the brain. She was manageable as she needed rarely to be handled but the other health problems started to add up and she was euthanised.
My friends 5yrs gelding had something kind of similar though not that extreme. He did go through episodes of bolting /panicked then back to normal.
Turns out it was his TMJ joints had massive chips and arthritis. He had ground breaking surgery at University of Saskatchewan in June and he’s been a completely different horse. And back to be ridden/jumping.
highly highly highly suggest you check out this public fb page. It’s run by the vet who did the surgery and he’s super.
https://www.facebook.com/groups/625206024604903/?ref=share
P.
I also think it could be something neurological.
I’m very worried about your safety!
Removing things from her diet, running bloodwork, and a neuro test are all in order, ASAP. I’d also do rads of her neck and spine, in case turning her head in just the wrong way is triggering some sort of extreme pain/reaction. Unfortunately, we don’t have great tools for figuring out what’s going on in the brain, and the ones we do have are not inexpensive.
4 times in 3 months is pretty significant. Make notes on all your management. What she’s eating, how soon after eating an episode occurs, what her body position was right before she started, etc.
First, never handle this horse without a helmet, appropriate footwear, and gloves. (this goes for anyone handling her, however briefly)
Second, please don’t let kids or novices near this horse, or handle her in any way. This kind of behavior could easily kill or seriously injure someone.
Third, I wouldn’t ride this horse or take her to a show until you’ve figured out a cause, and have been treating it to the point that it’s been twice as long between episodes as it has ever been. If she has an episode while you’re on her, it would be extremely dangerous. Similarly, if she is at a show with strangers and other horses around, especially in a confined, shared space like the temporary stabling areas, I could see something truly tragic happening! 
I would leave this horse out 24/7: individual turnout in a small enough space that she can’t really get galloping, with strong, visible fencing, and a run in. And any stall or run-in that she inhabits, I’d put up kick protection, in the form of mats hung off of 2x4s to absorb some of the concussion. It might also be worth looking at some sort of leg protection for her, though there aren’t really any great options for 24/7 use…
If you board this mare, I’d have a serious discussion with the BO/BM. Staff all need to know of the risk of handling this mare, and you also want anyone at the facility to keep an eye on her, and be able to report the 5Ws back to you, for your notes, if they witness an episode.
It’s also possible that you won’t be able to discover a trigger/cause. In that case, you may have to make some tough decisions. But if this behavior is as extreme as you describe, it’s not a question of ‘if’, it’s ‘when’, that somebody gets seriously hurt, or she seriously injures herself. I’m so sorry you’re facing this!
I was reading up on Lyme and came across another post from dwblover back in 2007 that said “First time I dealt with it the symptoms started as a refusal to pick up front feet to be picked out. Horse would stretch whole body back like he was going to lay down until you let the hoof go” She does this exact thing! This started maybe within the last 4 weeks. I guess I’ll add a lyme test to the list of things to rule out 
twinmommy- I’m curious to know how often these episodes would happen and their length? It sounds strangely similar- being terrified of something. From the onset of the episodes until losing the ability to stand, how long of a time period? And was the brain tumor identified post-mortem or prior? What a terrible situation- I’m sorry for your loss.
I had a gelding who would have random panic attacks similar to your mare’s. He would be fine one minute then bolt in a blind panic. He was quite dangerous during the attack but after the panic attack he would go back to his sweet quiet self. Vet exam showed enough evidence of severe neck trauma that I had the horse euthanized. Necropsy showed a spinal malformation (probably Wobbler’s.) Vet felt that horse would move a certain way and pinch a nerve which caused severe pain.
I’m a little overwhelmed with all these responses This is my young child’s show horse and purchased in the past year. I really was just thinking she was just under-worked and bored, testing us, or just heard bound as her worst behavior (aside from these episodes) is when her herd-mate is out of range. Luckily she isn’t boarded so I don’t have to worry about that liability- just my own family!
I’ve been keeping detailed records of incidents- looking back now it seems they might be more frequent than I’ve remembered.
I’ll get her back to the vet this week and have blood pulled. A simple neuro test was done a few days ago (tail pulling, tight circles, backing, etc). No issues. She also had a chiropractic exam/adjustment by a DVM. Only issue with that is he had an awful time getting her right leg/shoulder lifted to adjust. This goes back to what I mentioned in another reply- we’ve been having difficulty getting her to keep her front legs lifted.
I certainly don’t want to be a Debbie Downer! But the behavior as you describe it comes completely out of the blue and is extremely violent, irrational, and with no regard for her own safety. What would happen if your young child was holding the leadrope, or even standing next to the mare in crossties, while you duck into the tack room ‘for just a minute’ and the mare has an episode? Would your young child be aware enough to dive out of the way, or know what to do? If the horse is in a stall double barreling the walls, what makes you think she wouldn’t do that just because a person was standing there? I really, really hope you figure out a trigger, whether nutritional, medical, or whatever. But in the meantime, PLEASE be careful when handling this horse, and don’t risk your young child getting hurt. Or even if she escapes injury she might become scared of horses in general and want nothing more to do with them.
The way you describe the behavior – the way it comes out of nowhere, and then a few minutes later it’s as if nothing happened, doesn’t, to me, sound like a horse that’s buddy sour, bored or a little fresh from underwork, it sounds neuro. One more out of the box thought though, have you had her eyes checked? If her vision is compromised, perhaps a blurry shadow or something scares her, and she panics?
If you get in the habit of carrying your phone around, it might be very valuable to be able to video an episode and send it out for an opinion at the state U or a program that specializes in unusual presentations. Just seeing the horse’s body language while she’s spinning/kicking/running might provide valuable clues. Is it anger? fear? pain? directional? etc.
I agree that your child (or any child) should not be around this horse unless or until this behavior is figured out. I wouldn’t let my child ride her, either, as that could be equally dangerous.
Random explosions in horses scare the Hell out of me. If there is no way to predict the behavior then you can not protect yourself from it. I hope you get this figured out quickly.
What you’re describing sounds very much neurological to me as well–glad you’re aware of that angle and the vet is exploring. Subtle neuro stuff can really wreck havock with them and can take a very talented diagnostician to “see” it. This article might be of interest to you:
https://thehorsesback.com/c6-c7-malformation/
BUT, that said, I have 100% seen a horse act like this because of a raging case of gastric ulcers. Best guess is she was stoic about the pain until it got very bad, and then she lost her brain trying to get away from it. When I saw it happen, I really thought she was going to die, and that she’d just perforated her stomach or something…it was terrible, and scary. Gastrogard totally cleared her up.
I don’t want to sound pessimistic either, but one of the neuro tests my vet did was lift the horse’s front leg and lean into him slightly. The horse went down in a heap. One leg was worse than the other, but he responded the same way on each leg. The vet looked at me and asked if I was riding this horse and I replied “not anymore.” Ask your vet about this test and if he thinks you should do it.
I’m so sorry for your family and your horse. My horse was young and had a lovely personality when he wasn’t having a panic attack. I chose to euthanize him to keep him from hurting himself or any one else.
This is 100% a neurologic symptom. My inkling is to check the neck especially low down like C6 to T1, but it could also be from a systemic issue I suppose.
