Some breed effects on the melting point and fatty acid composition of carcass fat in lambs

Summary Two breed comparisons were made: (a) between Galway and Galway x Finnish Landrace (Fingalway) lambs, and (6) between Galway x Fingalway and Galway x (Finn x Texel) lambs, for the melting point and fatty acid composition of subcutaneous tail, subcutaneous 13th rib and perinephric fat. The lambs were slaughtered at market weight from September to January, being finished off on grass except for a small number finished indoors on concentrates and hay. Slaughter age and carcass weight, both of which had significant effects on some of the measurements, were included as covariates in the breed comparisons. Overall breed effects were small. The melting point of the fat from Fingalway lambs was lower than that of the Galway breed in each location, the difference being significant for subcutaneous rib fat. This was associated with a lower concentration of stearic acid and a higher concentration of oleic acid in each fat depot of the Fingalway breed, the difference being significant for oleic in subcutaneous tail and for stearic in subcutaneous rib fat. No significant breed differences or trends were observed for the other fatty acids measured. Results for a small number of pure Finn lambs supported the Finn ancestry influence indicated by comparison (a). In the second breed comparison, no significant breed differences were observed, the values being close to those obtained for the pure Galway lambs.