COMPARISONS OF FATTY ACID PROFILES IN BEEF FROM NGUNI,BONSMARA AND ABERDEEN ANGUS STEERS RAISED ON VELD

摘要

IntroductionRed meat has a relatively high ratio of saturated to unsaturated fatty acids (FA's), which is a risk factor for the development of cardiovascular diseases. The adverse effect of saturated fatty acids (SFA) on the human plasma cholesterol levels makes it imperative to evaluate FA profiles in beef. Polyunsaturated to saturated fatty acids (PUFA/SFA) and Omega 6 (n-6) to Omega 3 (n-3) ratios, and conjugated linoleic acid (CLA) are important because of their effects on obesity, cardiovascular problems and anticarcinogenic action (Moreno et al., 2006). Fatty acid composition is influenced by diet and genotype due to the underlying differences in gene expression or activities of enzymes involved in FA synthesis, desaturation or chain elongation (Barton et al., 2007). The majority of the available reports on meat quality in Southern Africa are based on established beef breeds, such as the Angus and the Hereford on cultivated pastures and feedlots in the sourveld (Strydom et al., 2000). No studies on FA profiles have been reported in cattle that are grazed communally on veld, without any form of dietary supplementation. In communal grazing cattle from different households are brought together and grazed in areas which are owned by communities with limited and inadequate veld management principles being applied, resulting in overgrazing and loss of weight, specially during the dry season. This may affect FA composition which is closely related to fatness (Zembayashi et al., 1995). Therefore, the objective of this study was to compare FA profiles of Nguni, Bonsmara and Angus steers raised Under natural grazing without dietary supplementation.