That's a good start and pretty horse.
#1: The lighting is nice, but as sky said, leave the same amount of room at the top and bottom
#2: Cute facial expression and nice positioning in the frame (with space to one side). Try to give him/her more space, the lower lip and ears are cut off.
#3: You are taking the picture from above the horse's level downwards. Try going lower, with you camera at the horse's height, keeps the proportions better. Posted via Mobile Device