Effect of vitamin E supplementation on antioxidant status of murrah buffaloes

Murrah buffaloes (24) in their advance pregnancy were distributed into four equal groups. They were supplemented with 0 (T₁), 1000 (T₂) 1500 (T₃), 2000 (T₄) IU dl-α-tocopheryl acetate (vitamin E) h⁻¹d⁻¹ respectively from 60 days prepartum to 30 days postpartum and the dose wasreduced to half in all the groups from 31 through 60 d postpartum. Blood samples were collected at −60, -45, -30, -15, -7, 0, 7, 15, 30, 45 and 60 days of parturition. Vitamin E intake was 221.2, 232.5, 252.5 and 226.5 mg/d during dry period and 246.2, 267.5, 279.5 and 255.5 mg/d during lactation in T₁, T₂, T₃ and T₄ groups respectively. Plasma α-tocopherol and retinol decreased by 54.54 and 19.48%; 48.30 and 28.75%; 32.43 and 21.69%; 26.42 and 19.74% on the day of parturition in the four respective groups as compared to 60 days pre parturition. Higher plasma α-tocopherol in T₃ and T₄ at calving helped to regain normal plasma vitamin E status for better immune function, within two weeks, whereas T₁ and T₂ required more than four weeks to reach this level. Though the Plasma total antioxidant activity (FRAP Values) 60 days before calving did not vary significantly (P>0.05), but the values continued to decline from 30 days pre-partum till calving in all the groups. The decrease in plasma antioxidant status at calving was 39.91, 29.65, 18.60 and 16.67% in the four respective groups. On the day of parturition, FRAP values were significantly higher (P<0.01) in T₂, T₃ and T₄ groups than T₁. The data indicated that the extent of decrease in the levels of α-tocopherol and total antioxidant activity at parturition could be reduced by supplementing vitamin E during dry period.