Abstract
The aim of this study was to evaluate the growth performance, antioxidant status, meat fatty acid composition, antioxidant status, and health of sheep received diets supplemented with plant essential oils. Growing lambs (n= 20) were randomly allotted into four groups: control (CON) group received a fattening standard diet with no additive, the second group received the CON diet supplemented with 5g/kg DM of black cumin seed oil (CUMO), the third group received the CON diet supplemented with 5g/kg DM of cinnamon oil (CINO), and the fourth group received the CON diet supplemented with 5 g/kg DM of pomegranate seed oil (POMO) for a period of 8 weeks. The body weights of lambs were greater in the CUMO group than the other groups (P = 0.03). Bodyweight gain and daily feed intake of lambs fed diets supplemented with plant oils were not different from those fed the control diet. Lambs fed the diets supplemented with CUMO had improved FCR (P = 0.005) compared to other groups. The experimental diet containing CUMO, POMO, and CINO significantly decreased blood MDA levels (P < 0.001). Lambs fed the diet supplemented with CUMO had greater blood GPx values (P < 0.001) than other groups. Lambs fed CUMO, POMO, and CINO supplemented diets had greater serum total protein and globulin concentrations (P < 0.001), while lower serum cholesterol levels than those fed the CON diet. The ALT concentration was lower (P < 0.001) in the serum of lambs fed essential oils supplemented diets. The POMO lambs had lower serum AST levels (P < 0.01) compared to other treatments. Lower proportions of SFA (P < 0.001) and MUFA (P < 0.001) were observed in the CUMO, POMO, and CINO supplemented groups compared to CON. Dietary CUMO supplementation increased PUFA (P < 0.01) and n6-PUFA proportions (P < 0.05) compared to other groups. The CUMO and CINO groups had greater n3-PUFA (P < 0.05) than other groups. In conclusion, dietary supplementation of CUMO, CINO, and POMO was a good approach to improve antioxidant status, health, and meat nutritive value of feedlot lambs.

Key words: Lambs, essential oils, meat fatty acid, antioxidant status, blood constituents