Sire and dam breed effects on fatty acid profiles in the longissimus dorsi muscle and subcutaneous fat of beef cattle

This study investigated the effect of sire and dam breed on the fatty acid proles of muscle and subcutaneous fat in beef cattle. Seven hundred and ninety-three steer and 222 female progeny derived from mating Angus and Hereford cows to Angus, Hereford, Limousin and Simmental bulls, were slaughtered at around 2 years of age (about 540 kg liveweight). The mean fat content of the longissimus dorsi muscle ranged from 4.6% for the Limousin-sired cattle to 6.0% for the Angus-sired cattle. Breed differences occurred in the majority of fatty acids from the intramuscular fat, but fewer differences were observed from the subcutaneous fat. The Limousin- and Simmental-sired progeny had less (P < 0.001) saturated fat and more (P < 0.001) unsaturated intramuscular fat compared with the Angus- and Hereford-sired cattle. The Angus and Simmental cattle had more (P < 0.001) monounsaturates than the Limousin and Hereford cattle. There were differences (P < 0.001) in the level of intramuscular polyunsaturates between all 4 sire-breeds, the Limousin having the highest and Angus the lowest. Simmental progeny had significantly higher levels of polyunsaturated fatty acids, compared with the Hereford-sired progeny, as well as a higher monousaturated : saturated fatty acid ratio. Hereford-sired progeny had a lower (P < 0.001) monousaturated : saturated fatty acid ratio in the intramuscular fat. Intramuscular fatty acids were affected by dam breed, with progeny of Hereford cows having a higher percentage of unsaturated fatty acids (P = 0.015), lower saturated fatty acids (P = 0.011), and a higher monousaturated : saturated fatty acid ratio (P=0.028) than those of Angus cows. There was no effect of dam breed on the totals of the different fatty acid groups in the subcutaneous fat. The subcutaneous fat had higher levels of saturated fatty acids and lower levels of unsaturated and polyunsaturated fatty acids compared with the intramuscular fat. Although the differences reported were generally small, it would seem that there may be scope to utilise these genetic differences to produce meat with more desirable fatty acid characteristics.