The need for water is one of the basic motivating forces for all animals. Only a lack of air and severe pain initiate a greater response by animals than thirst. Thus, one of the five freedoms in evaluating animal welfare adopted by the UK Farm Animal Welfare Council is the "freedom from thirst, hunger and malnutrition" (Webster, 1996). However, there are contradictory views on how much water a horse needs and how best the water should be delivered.