EFFECTS OF SUPPLEMENTAL VITAMIN-E AND CANOLA OIL ON TISSUE TOCOPHEROLAND LIVER FATTY-ACID PROFILE OF FINISHING SWINE

We conducted a 4 x 3 factorial experiment with finishing pigs for 6 wk to evaluate effects of dietary canola oil and vitamin E on vitamin E status and liver fatty acid profile. Treatments consisted of four supp lemental levels of vitamin E (0, 50, 125, and 200 mg/kg) and three of canola oil (0, 5, and 10% of the diet). Serum was collected each week and tissue samples at d 42. Dietary canola oil (P = .02) and vitamin E (P <.001) increased serum alpha-tocopherol. Serum alpha-tocopherol re ached a plateau at d 35 of vitamin E and canola oil supplementation. A n interaction was observed between canola oil and vitamin E (P = .02) for liver alpha-tocopherol. Liver alpha-tocopherol was greater in pigs fed diets with 10% canola oil and supplemented with 125 or 200 mg/kg of vitamin E than in pigs fed diets with 0 and 5% canola oil. An inter action also occurred between canola oil and vitamin E (P =.01) for alp ha-tocopherol in the gluteus medius and obliquus capitis caudalis musc les. A greater magnitude of increase in muscle alpha-tocopherol was ob served in pigs fed diets with no canola oil than in pigs fed diets wit h 5 and 10% canola oil. Highest alpha-tocopherol was in liver, followe d by obliquus capitis caudalis and then gluteus medius. Inclusion of 5 or 10% dietary canola oil decreased the amount of saturated fatty aci ds by 4.1 and 13.5%, increased monounsaturated fatty acids by 10.9 and 39.3%, respectively, and had no effect (P >.10) on total polyunsatura ted fatty acids. Canola oil increased linoleic acid [18:2(n-6)] (quadr atic, P =.05) and linolenic acid [18:3(n-3)] (linear, P <.001) while d ecreasing arachidonic acid [20:4(n-6)] and docosadienoic acid (20:2) l inearly (P <.001 and P = .02, respectively). Dietary canola oil and vi tamin E increased serum and tissue alpha-tocopherol; canola oil increa sed monounsaturated and decreased saturated fatty acids in liver.