Why does my horse get too excited around cattle?

A horse that becomes excessively excited around cattle — jigging, pulling, hollowing its back, and losing responsiveness to the aids — is displaying an arousal response that its training has not yet learned to regulate, and the cause is almost always some combination of natural cattle drive, insufficient cattle exposure at controlled arousal levels, and a training history where cattle work always meant high-speed, high-intensity runs. Natural cattle drive is a desirable quality in a rope horse — a horse that wants to get to the cattle is easier to develop than one that is indifferent — but that drive must be channeled through the training rather than allowed to override it. The horse with strong cattle drive that has only ever experienced cattle at a gallop has learned that cattle mean maximum effort and adrenaline, and it begins producing that physiological state the moment cattle appear. The correction requires separating cattle presence from high-intensity work: spend time near cattle without chasing them, walk and trot around settled cattle with no expectation of a run, stand quietly near a pen of cattle and ask the horse to relax rather than depart. The horse needs to learn that cattle being present does not automatically mean the run is on. Over many sessions of low-pressure cattle exposure at varying intensity levels, the horse's arousal response to cattle becomes more graduated — it can be near cattle without immediately peaking — which gives the rider the ability to manage the horse's energy rather than being carried along by it.