Heritabilities of triacylglycerol fatty acids from the adipose tissue of beef cattle at weaning and slaughter

A first attempt at estimating the heritabilities of total saturated (SFA), monounsaturated (MUFA)and polyunsaturated (PUFA) fatty acids from the triacylglycerol fraction of adipose tissues is presented. The data were from subcutaneous fat biopsies of 324 weaner steers and heifers across 7 genotypes and 26 sires. These animals all went into the feedlot postweaning, but the carcases of 150 at slaughter were sampled for fatty acid analysis. Results showed that weaner SFA, MUFA and PUFA had heritability estimates of 15, 16 and 0% respectively. At slaughter, estimates of heritabilities were 23, 57 and 15% for SFA, MUFA and PUFA respectively. Since monounsaturated fatty acids are highly desirable given their cholesterollowering ability, this study suggests that selective breeding for MUFA has a good prospect of making genetic progress given the high hL of 57%. A larger data set would shed more light on the precision and accuracy of the estimates presented since these are based on a small data set.