Background – Ruminant depot fat has a high saturated fatty acids (SFA) to polyunsaturated FA (PUFA) ratio due to ruminal hydrogenation of dietary FA. However, the lipid contained in trimmed lamb (intramuscular fat) contains a higher proportion of PUFA and omega-3 (ω-3) FA than depot lipid and may provide important sources of these FA.
Objectives – To determine the variation in muscle FA between genotypes in 14 month old yearling sheep.
Design – One side of 147 carcasses from five genotypes (pure Merino=Merino; Border Leicester x Merino= BLM; Poll Dorset selected for growth x Merino=PDgM; Poll Dorset selected for muscling x Merino= PDmM; PDg x BLM= 2X) of sheep maintained under the same grazing conditions were used. Carcass lean and fatness, entire loin muscle weight and muscle FA composition were determined.
Outcomes – Carcass fatness (%) increased in an ascending order from Merino to Poll Dorset to Border Leicester genetics. Muscle lipid, SFA, PUFA:SFA ratio and omega-3 FA did not differ between genotypes.Conclusion – These data indicate that consumption of one serve of yearling sheep meat (150 g) would contribute 120 mg of long chain ω-3 FA to their diet, which is 24% of the suggested daily allowance recommended by the National Health and Medical Research Council 2005.