Changes in body composition relative to weight and maturity of large and small strains of australian merino rams. 4. Fat depots and bones

Abstract

ABSTRACTMaturing patterns are established for the weight of bones relative to the weight of total bone and for the weight of fat depots relative to the weight of total body fat in two strains of Merino rams of different mature size. The maturing coefficients for all bone and fat depots are tabulated.In the mature animals the partitioning of fat in each strain was similar, except for scrotal fat which was more abundant in the smaller strain. The maturity patterns of the depots were not different for the strains and also not different from the pattern of total fat, except in the case of scrotal fat. Accordingly, comparisons of the partitioning of fat were similar at equal maturity to the comparisons made at equal weight.The distribution of weight among the bones was similar at maturity for both strains. However, unlike the fat depots, the individual bones had maturity coefficients which were mostly different from that of total bone. The limb bones, with the exception of the scapula, were early maturing relative to total bone. Accordingly, when compared at equal weight, limb bones, except the scapula, were a higher proportion of total bone weight in the larger strain and the differences between the strains were reduced when compared at equal maturity.A summary of conclusions from this series of papers shows that tissues and organs had similar maturity coefficients in both strains of rams, and that stage of maturity was important in comparisons of proportions of tissues which have maturity coefficients which differed greatly from 1·0, but of little consequence where the maturity coefficient was close to 1·0