Studies on the distribution of the body fat in sheep during continuous growth, and following nutritional restriction and rehabilitation

Abstract

Merino wether sheep were completely dissected at c. 3,6 and 12 months of age following steady growth. Further 12-month-old animals were subjected to nutritional restriction producing a liveweight loss of some 25%; dissections were carried out at this point, and following a 30% rehabilitative gain in liveweight. Two animals were involved at each dissection point. Total body fat was separated into the dissectible visceral, intermuscular and subcutaneous

The restricted animals contained the same amount of fat per unit of wool-free empty body weight as did those grown continuously, but the rehabilitated animals did not. Rehabilitation was associated with the accumulation of less fat and more protein and water than occurred during steady growth.

Nutritional restriction caused a relatively greater loss of fat from the subcutaneous depot than occurred through the body fat as a whole, and some further deposition of fat occurred in the skeleton. This resulted in the restricted animals having, at comparable amounts of body fat, a significantly lower proportion in the subcutaneous depot and a higher proportion in the skeleton than had continuously grown animals. Rehabilitation to the degree employed in this work did not restore the normal contributions of those fat depots to total fat.

Total intramuscular fat could not be predicted from the fat content of samples from five superficial muscles, nor was the relationship of intramuscular fat to total body fat sufficiently close for predictive purposes.