The determination of body composition of living animals

In many nutritional and metabolic experiments it is desirable to know the mass of one or both of the main components of the animal body, namely storage, or non-essential, fat and lean body mass (L.B.M.) (Behnke, 1941-2).These components, together with the gut contents, make up the live weight of the animal.Fat is the most variable of the three, and in many nutritional and dietary experiments its size is important.However, as it is not an actively metabolizing tissue, for some purposes it is often sufficient to know the size of the L.B.M. only.The constancy of the composition of the L.