In the last month or so he has gotten really mean on the ground. When I clean his stall he pins me in the corner and often tries to bite or kick me. Sometimes he is successful. He also will do this when I blanket him. He usually has his ears pinned back when you approach his stall, or when you are in it.
When I put him in the cross ties to tack up he doesn't like me to pick his back feet. He has always been like this, but lately he tries to kick out more.
When I brush him on his right he tires to bite and kick me. It's nearly imposable. I have tried several different brushes and I brush him really gently. He is nicer when I brush his left. He used to try and bite me when I girthed him but he has since stopped that. He also pins his ears back for nearly the whole tack up process.
YET! When I mount him he is a perfect angel. After I ride him he is tolerable and only gets mean when I brush him after taking off the tack but not as mean as he is in the beginning.
I am sure quite sure what to do. I recently switched him to alfalfa hay from grass. Which has helped him put on the weight he needed. Supplement wise he is on oats and coolstance with some vitamin e. I was going to try and take him off the oats this week and see what that does.
I am training him in the hunter/jumper discipline.
Does anyone have any idea or suggestions? Or has anyone had a horse like this before?