Performance, Meat Quality and Gene Expression of Grazing Lambs Supplemented with Macadamia Oil and Vitamin E

Macadamia oil has high concentrations of oleic and palmitoleic fatty acids, which can increase tissue sensitivity to insulin, improving glucose absorption efficiency, and reducing lipogenesis through gene modulation. The objective of this study was to evaluate the effects of macadamia oil associated with vitamin E supplementation on performance, blood parameters, meat quality and sensory characteristics, meat fatty acid profile, and expression of genes associated with lipid metabolism in grazing lambs. The experimental treatments were control diet (Control), Control + 0.1% of body weight of macadamia oil (MO), MO + 745 IU of vitamin E/dry matter (MOVE). Macadamia oil improved feed efficiency, reflecting a lower dry matter intake, as the average daily weight gain did not differ from Control. Meat quality parameters were not affected by macadamia oil or vitamin E supplementation. Supplementation with macadamia oil improved meat appearance, flavor, and overall liking. Supplementation with macadamia oil provided a higher proportion of C18:3 n3 and a lower proportion of CLA. The expression of SREBP-1c, PPAR-α, SCD1, and ELOVL6 genes were not modified with the supplementation of macadamia oil and vitamin E. In conclusion, supplementation with macadamia oil improves feed efficiency and meat quality; and the inclusion of 745 IU of vitamin E/kg of dry matter for grazing lambs reduces 36% of lipid oxidation of the meat.