 Many different schemes exist, giving various values to the grazing effect of different types of animal.Livestock grazing comparison units are used for assessing the overall effect on grazing land of different types of animals (or of mixtures of animals), expressed either as a total for a whole field or farm, or as units per hectare (ha) or acre.For example, using UK government Livestock Units (LUs) from the 2003 scheme a particular pasture field might be able to support 15 adult cattle or 25 horses or 100 sheep