Gaping mouth

looking at a mare for HUS, OF & RR. I am seeing a moderate amount of mouth gaping in her videos. Trainer of couse says it was the first time she was in that bit etc. Mare moves really nicely.
How hard is it to correct that? It is not an issue I’ve ever had to deal with before. If it’s difficult it is probably not worth the time to go look at her…

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What bit is she in in the video? What bridle? Is it an open bridle or does it have a cavesson? Who was riding her? How well was the rider riding? Can you post a video (IDK if sales videos are allowed)? Why was she in a new bit for a sales video?

All questions to ask yourself and the seller and your trainer. Then tell us! :smiley:


solid mouth, no cavesson, trainer riding, riding OK as far as I could see. Can’t link the video, was supposedly just trying a new bit on her, no specific reason (at least that they would fess up to…)

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Then why did they choose to use THAT video as the sales video?


This was my thought as well.

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Curb? Snaffle?

no clue.

What I am trying to figure out is if this isn’t because of all the excuses I’m being given, how hard is it to correct?

Mullen mouth bits can get wedged at an angle in the horse’s mouth if the rider is not used to a Mullen mouth bit, &/or neglects to release the single rein aid completely and let the bit get to its normal place before using a single aid on the other rein.

In other words this is why the lesson horses I ride DO NOT LIKE me riding them in a Mullen mouth snaffle, a Mullen mouth Kimberwick is barely bearable, and a Mullen mouth Weymouth curb is fine since I do not direct rein a turn signal in a Weymouth curb.

You might ask for another video with the horse’s usual bit in her mouth to see if she gapes in another style of mouthpiece.

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They had another. Still gaping, but much less.

So how hard is this to correct?

Just bear in mind that “gaping mouth” (specifically “Mouth opening ± shutting repeatedly with separation of teeth, for ≥10 sec”) is one of the 24 behaviors in the Ridden Horse Pain Ethogram (RHpE). A horse showing 8 or more of the behaviors is “likely to indicate musculoskeletal pain”, in horses that are thought to be perfectly sound.

You can google it, but you also look at,likely%20to%20reflect%20musculoskeletal%20pain.


The only thing that is apparent on the video is the gaping. May see others when see the horse in person, but for right now this is it. Trying to figure out, assuming there is not pain in the mouth etc how hard this is to correct. If it is next to impossible to correct, I don’t want the spend the time & $$ going to see her.

So ask for a video of horse in the old bit and see if she gapes. I bet she’s worse in the old bit, is why they switched. Fixing a symptom like this requires finding the cause whether body pain or dental or bad bridle fit and yes, pain reactive responses can become habits

If you are paying top dollar and want a show horse, I’d pass. If you like projects and she’s a bargain buy her. I might buy but I have lots of time and ideas to fix things and no showing goals.


thank you

I do not ride Western (or dressage for that matter) so if I got put up on a Western trained horse I would be feeling my way.

I ride Forward Seat (a variety of hunt seat). My main mantra while riding on contact is that my hands belong to the horse’s mouth. I work the horse on the lightest contact possible to get obedience. I rarely take a dead hold on a horse’s mouth (mainly because most horses will gape at least a little bit when I do), I give a rein aid followed by an immediate full release when I am re-training a horse. I have MS, with a compromised central nervous system, so I take my cues from the horse instead of what the horse is “supposed” to do.

Thinking back I did retrain a horse who had originally been trained Western, then became a hunt seat lesson horse. He was NOT a good lesson horse, that is why I ended up on him.

It took me several months to “deal” with his gaping mouth. His gaping mouth had developed because no one in his life (he was in his late twenties) had ever bothered to teach him what a proper response to the bit was. He came to me convinced that all riders were out to torture him and he was just trying to defend his sensitive mouth (even a horse who feels like their jaws are made of wrought iron which is rusted shut can develop a sensitive mouth, don’t give up.)

I had to take a dead hold on his mouth at first whenever I wanted him to stop, or when I asked him to back up. It took many months, but basically I released my aid when I felt like he was taking even the tiniest step toward obeying my hands. Going down to a halt I released my aids momentarily when it felt like he was not pushing as hard with his hind legs, and at the beginning each halt required A LOT of hand aids/release before he would consent to halt. Backing up I would release the instant that I felt him shifting his weight a little bit to the rear, usually before he even moved a leg, and again in the beginning it took a lot of the back up hand aids before he would actually pick up a foot and move it back.

At one thirty minute ride a week it took me around a year until he developed a really nice sensitive mouth on contact and he softly responded to my hand aids. Even then any confusion, big distraction, or just because he did not feel as good that day would result in him gaping when I asked for a halt, etc. and his darn iron jaw that was rusted shut would reappear for a little bit.

If you buy this mare be prepared to go back to the beginning of saddle training. As I say of the lesson horses I ride she is showing gaping chasms the size of the Grand Canyon in her basic training, the training where the horse is supposed to learn its ABCs.

It’s impossible to know just from a video how hard it might be to correct this problem. If you otherwise like this horse and she isn’t too far away, why not go take a look and see for yourself? Is the horse also wringing her tail in the video? Tossing her head? Some bits have sweet iron or rollers that horses like to play with–I assume that’s not the case here?

Mouth gaping could be caused from the bit sitting too high or too low in the mouth. Or it may pinch on the sides. Or the mouthpiece may not suit the horse (too thick or too thin). Or it may be a harsh bit. Or the horse may need her teeth floated. Or maybe the rider is too heavy handed with the reins. Many (maybe even most) mouth gaping problems are caused by issues such as these that are easily solved by making sure the bit fits and sits comfortably in the mouth and the rider is using a loose rein (for Western style). It would be interesting to know what bit is in this horse’s mouth, and why they decided to try a new bit on her.

Or it may be a bad habit, and that would be harder to fix.


I never buy a horse assuming i know more than the seller. If the seller can’t fix this issue, I wouldn’t presume to be able to myself either. Can you live with it if you can’t fix it? if not, pass.

it could be the horse needs a vet, it could be a training hole (a massive one) or it could be a poor choice of bits. It could be a combo of those things. I don’t think one ride will give you the answer.


It’s not so much a question of how hard is it to "correct"as it is a question of why the horse is doing it. As Janet says, it can be a sign of pain.

I suggest you go see the horse in person, with your trainer, if you can.

I find most gaping issues to have to do with level of anxiety rather than type of bit. Fix the anxiety and the mouth gets quieter. How hard is that? Depending on how deep seated the anxiety is and whether you can take the cause away.


It can be a longer term fix, but not impossible. The fix really depends on the cause, as Showbizz mentioned, it can be rooted in anxiety, as well as pain. I wouldn’t necessarily say it’s an “easy” fix because every horse is different and in the 4 horses I’ve dealt with on this specific issue, fixing the gaping took no less than 3 months. I’ve found it has also been strongly rooted in the way they have been trained, so there is really no shortcuts due to the need for retraining. It usually takes me 3-4 months (depending on your feel) of going back to basics, ground-up, to really fix this issue. If the issue is rooted in the bit, then the fix should be quick and simple.

The first horse I ever worked through this issue was actually my own. With him, I knew exactly where it came from and had his bit fit and type suggested by a vet via mouth conformation. He had been trained for one month by a trainer who was rather rough on the mouth before I was really aware of it all. This was really early in owning him, so I was learning too. He was supposed to stay for 3 months but I pulled him at one. It took YEARS to fix the issue because no trainer I worked with was really familiar with how to fix it. What didn’t work was band-aid fixes (flash noseband), holding contact, loose rein, working him through it, any exercise. He could go really well, but as SOON as he got anxious, he would start gaping. Eventually, I just decided to try working him from the ground up. I started with 5 minutes of showing him how to position himself, while I walked beside him. Moved into asking him to step forward from the hind end and stretch into contact. Immediate reward when he put ‘weight’ into the bit. We expanded on this until he could do a lap around the arena and keep contact while leg yielding and shoulder-in on the ground. Because of his height, this was a lot easier to do than a horse above 16hh. Then I moved to undersaddle, same exercises at the walk, then trot, then canter… With each transition, I started with 1-2 strides and focused specifically on him reaching for the bit. Until he did that, I did not ask for more steps of trot or canter. The gaping NEVER came back after that and he had learned to seek the bit wherever and whatever speed he was at, but it did take a good amount of time of just walking and sticking to the ground. Overall, I’d say 3-5 months of gradual work, mostly sessions <20minutes and most of those ground and walk sessions were less than 15minutes. I supplemented that with trail riding on hills and lunging over poles to develop the necessary muscles needed for the topline.


Hard to say for sure.

Was the bit too tight and pulling on the corners of the mouth?
Does the horse not understand how to give it’s mouth to pressure?

I know you are asking “how hard is this to correct” but it kind of does depend on the reason why it is there. It could be something very easy to fix, or it could be an engrained bad habit that could take a long time to fix.

It is a little weird to choose a poor video for a sale video.

You could ask them to provide another video, and see if it looks any different. Everyone’s got smart phones these days. It’s way too easy to take another quick video, and text/email it.