Never mind. I know where I am now lol
My first job as a teenager was taking care of 25 horses in a boarding stable. My job was to let them into their stalls and feed them etc... Each horse had a definite personality. Some were kickers. They would put their nose in the feedbox and start kicking behind them immediately as a reflex action. Others were biters and some were gentle. The stallion's stall was completely enclosed in strong fencing material. I was not allowed to feed him until the owner or an experienced assistant could go in and lead him out of the stall.
Some of the horses were stump-suckers. They would grab their stall door with their teeth, bare their gums and inhale forcefully. They did this until the wood was all chewed up and the owner had to coat the wood with tar to prevent this behavior.