Chemical fat in the musculature of the sheep carcass

Abstract

SummaryForty merino sheep of mixed ages including lambs, ewes, wethers and rams were slaughtered and dissected. The chemical fat content often muscle groups in each sheep was measured directly and the mean value for the musculature of the whole carcass calculated.A characteristic pattern of chemical fat deposition was shown with the intercostal muscle group and the abdominal group being consistently highest in fat content, the shin and hind-limb muscles lowest and other intermediate. The pattern of growth of intramviscular fat was consistent with differences in activity of the muscle groups in the maintenance of posture. It was postulated that variations in fat content in muscle groups are affected by differences in blood flow.A highly significant relationship was established between dry matter and chemical fat content for each of the muscle groups. The regression was characteristic for each muscle group, and differed for most groups.Regressions between individual muscle group fat and that of total musculature fat revealed that no group was consistently the best predictor of the total carcass musculature fat though there was considerable difference between the groups. It was concluded there is no group which could be used for prediction purposes commercially.In a group of 14 other ewes subjected to weight loss up to 30%, and half of which were implanted with resorcylic acid lactone, no discernible effects on muscle group fat content were revealed.