I have a pony the is terrified of loading into the trailer. He becomes a completely different horse when being loaded. Houdini will rear, kick, bite, or anything else to avoid the trailer. A little over a ago he was kicked by another horse and broke his jaw in the trailer. We spent about six months healing from it, but now he won’t have anything to do with the trailer. I’m not sure what to do at this point to correct the behavior, he’s normally the most well behaved out of any horse in the stable.
Start from the beginning and retrain him how to load. Are you using the same trailer he was injured in?
Maybe this is a combination of fear and the fact that he was never taught to load in the first place. So many horses just get on the trailer with no issue and then the day they decide they don’t want to( for whatever reason) you have no training foundation to fall back on.
John Lyons has a great method to teach trailer loading.
It takes time, but very much worth it.
I’d treat him like a horse that has never been trailered before in his life. Start from scratch. One foot in, one foot out. Good basic ground work.
I have Clinton Anderson’s trailer loading DVD and it’s very good. Obviously, I don’t care to progress as aggressively or quickly as he does, but the same basic principles work very well. You teach the horse basic ground manners. When you are able to control the horse’s feet at all times, then trailer loading is a breeze. Might take you weeks or months of consistent training to get there, but if you’ve done your homework and not left any holes, he should load fine.
A horse that rears, kicks, and bites has some serious ground work problems. I could care less if there was an injury in the past – that’s still no excuse for the horse (pony) to behave that disrespectfully.