TOP, LEFT TO RIGHT: Mouth restraint. Hold the head down with one hand and insert the thumb of the same hand into the gap between the horse's teeth, gently pull the tongue out through the gap and hold it outside the mouth. ABOVE, LEFT TO RIGHT: A balling gun or dose syringe can be used while you mouth-restrain a horse. Hold the tongue out and insert the applicator into the toothless gap, then push the instrument over the tongue. The last photo shows how far the applicator needs to go back into the animal's mouth.