Walk your dog around the outside of fields with horses slowly bringing the dog closer and every time the dog makes the slightest attempt at barking or lunging at the stock jerk him sharply on the rope with a very sharp leave, slowly and gradually lemgthen the rope ie distance between you and the dog ,let him get nearer the horses if he is fine get in the field with them ,dog still on rope and start him close to you then slowly build up the distance .
All dogs get used to cattle sheep horses etc with the proper training .
I dont want to start a debate on shock collers but I have been trainin