I've used a dressage whip with my OTTB since pretty much since the day I got him, 6 months ago. He's not smacked with it or anything, but I do tap him with it to get his hind end going, but all it takes is a light tap or even a touch. Never got upset about it, even in the rare occasion I had to smart him with it, he never got upset about it either.
But, about 2 weeks ago, I lightly touched him with it on his hind end as we were trotting and he kicked out! I was shocked, this horse has never bucked/reared/etc ever!
At the halt if I touch him with it he pins his ears but thats it, at the walk he pins is ears, at the trot he kicks out, at the canter he pops off his hind end kicking out. Doesn't matter which side.
I know the easy solution is to not use a dressage whip, but its a tool that is very helpful to us and he really kinda needs it.
I thought it was cold-weather induced, but our barn is heated and he still does it when it isn't freezing.
What in the world? Did he just decide he doesn't like it anymore, or is there another reason?
WHERE are you touching the horse? Behind the leg (to support it) or just anywhere. Watch yourself and see. If you hand is thumb down/whip horizontal you are likely hitting the flank or croup, which can be irritating. Or, you could have the horse too low/closed/contained, and he cannot go more in that problematic balance, so there is tension.
That said, if you are touching behind the leg and he is kicking, you must follow up with another vibration UNTIL there is no kicking (if it is 20 times). However, you cannot touch and hold, have the horse positioning correctly, no spank and hold.
And, are you using the whip progressively: First aid is a mere touch (very light/touching hairs), second is a soft vibration, and only then do you do to a touch whip can be heard.
You might want to work with this in hand/on the ground. Big turn on forehand, touching when the inside hind is to move, touch/step/touch/step. INSTANT stronger fleck if the horse kicks out (as many times as it takes), then just stand quiet, reward, repeat. THEN do the same thing mounted (with the ground person acting to follow up the leg if need). THen on your own.
Another vote for "check your saddle fit". If he's become sulky about going forward in general, and you touch with the whip, he may feel you didn't hear his "mild" objection and so is getting louder (kick out, etc.)
Has his weight changed with the winter?
Another possibility: Are you careful to allow him forward when you ask for it? If you're catching him in the mouth or unprepared to go with him when you use your whip, he could be getting defensive.
I've seen this from time to time. Sometimes it's just a 'let's try this' response - they may do it as a one-off, and if they feel that you back off in any way as a result, they think HA! And will do it again. When you touch the horse, if their reaction is to buck/kick/suck back or basically respond in any way other than the desired forward reaction, sometimes following it with a quick bump of the leg, to say, Hey! Go forward! will twig to them, oh, that didn't work at all... often if you just repeatedly tap them, they will just continue this cycle of tap/kick/tap/buck/repeat, often escalating. Really pay attention after one tap - did the horse go forward?? If not, do what you need to do to get him to. If he gives a little kick but then reacts correctly forward, praise him for the forward part.
The other aspect is your own timing with the whip - my instructor used to say that a smart rider taps when the corresponding hind leg is coming under. An example of this: if a horse really has a habit of kicking at the whip, I will play on a circle, making sure they're really bending around my inside leg, and then tap them on the inside hind - it's pretty hard to kick at the whip when that inside hind is farther under their body. Also if they're really convinced it may help to think a little leg-yield away from that inside leg on the circle.
Of course this is all assuming your saddle fits and the horse isn't in pain, etc etc etc. But considering it sounds like the horse ONLY does this when you touch him with the whip, I would venture a guess it's directly related to the whip. Unless he's completely resenting going forward, which can be a discomfort issue.
Sometimes horses have to be 'trained' to give the correct response to the whip. Otherwise they get creative.
Thank you for the responses! I will double check saddle fit, etc.
He doesn't seem against going forward in general, no more than usual.
I tried to be very careful when/where I touched him with it when I rode last night, and it was a bit better but he still kicked out at the first touch, if I kept it on him (not hitting him with it but just kept the whip touching his body) he stopped reacting and was fine, but if it left his body and touched him again he was pissy all over again!
I will check for physical issues, and be more conscious about if I'm holding him in too strongly, and see if the issue continues.
Also try it on the ground, leading him at the walk and trot as you ask him to move out more and see what his reaction to it is then. If he's OK getting tapped with it from the ground as you ask him to move out, then it's likely something to do with riding, saddle, etc. Be sure to allow him to move out when you do it.
I think the horses in the Barn have been chatting during the late night hours and he has decided that you don't need it, afterall, he is a TB and his energy level is always at forward, you just have to ask and not tell.
Hmm- not much evidence for sudden bad saddle, pain, etc. Sounds like "ooh you hit me, maybe i will try this- oh yea, you stopped- if i repeat, maybe you will not use that horse killing stick, then when i have you trained for this, i will kick out when you put your leg on, and maybe i can teach you that walk and eat are the best gaits"
I would keep tapping/smacking the beast until he did not kick out/up and went forward- assuming you are putting your leg on at the same time so he knows it means go.