The effect of dietary vitamin E and fatty acid supplementation of pregnant and lactating ewes on placental and mammary transfer of vitamin E to the lamb

Abstract

The present study investigated the effect of maternal vitamin E and fatty acid supplementation on lamb antioxidant status. Forty-eight ewes were fed one of four concentrate diets supplemented with a basal (50 mg/kg) or supranutritional (500 mg/kg) level of vitamin E plus a source of either saturated fat (Megalac w ; Volac Ltd, Royston, Hertfordshire, UK) or long-chain PUFA (fish oil) from 6 weeks prepartum until 4 weeks postpartum. Blood samples were taken from ewes and lambs at intervals throughout the experiment and, at parturition, muscle, brain and blood samples were obtained from twelve lambs (three per treatment). Colostrum and milk samples were obtained at 12 h and 21 d after parturition, respectively. Supranutritional vitamin E supplementation of the ewe significantly increased concentrations of vitamin E in neonatal lamb tissues although plasma concentrations were undetectable. A significant increase in lamb birth weight resulted from increasing the dietary vitamin E supply to the ewe. Furthermore, maternal plasma, colostrum and milk vitamin E concentrations were increased by vitamin E supplementation, as were lamb plasma concentrations at 14 d of age. Neonatal vitamin E status was not significantly affected by fat source although plasma vitamin E concentrations in both ewes and suckling lambs were reduced by fish oil supplementation of the ewe. Fish oil supplementation reduced vitamin E concentrations in colostrum and milk and the activity of glutathione peroxidase in suckling lambs. The data suggest that the vitamin E status of the neonatal and suckling lamb may be manipulated by vitamin E supplementation of the ewe during pregnancy and lactation.

The effect of fish oil supplementation of pregnant and lactating ewes on milk production and lamb performance

“…Ewe blood samples were obtained by jugular venipuncture into evacuated plasma tubes containing potassium oxalate at 1100 h on day 103 of gestation and at 12 h, 14 days and 28 days post partum. Milk samples were taken from ewes using a method detailed by Capper et al (2005). Milk samples were taken and stored at 2208C before analysis.…”

“…Chemical analyses Feed samples were taken weekly and combined to give two samples per diet, which were analysed for dry matter (DM), ash, CP and NDF as detailed in Capper et al (2005). Plasma was separated by centrifugation at 2290 3 g for 5 min before storage at 2208C.…”

“…Fatty-acid analysis was achieved using a PerkinElmer 8500 gas chromatograph (PerkinElmer Life and Analytical Sciences Ltd, Boston, MA, USA) comprising a 50 m 3 0.22 mm internal diameter fused silica capillary column (model number 50QC2/BPX70 0 Á 25; SGE International Pty Ltd, Ringwood, Victoria, Australia), a flame-ionisation detector and a PerkinElmer AS 8300 autosampler (SGE International Pty Ltd). Fatty-acid separation and identification details have been reported previously (Capper et al, 2005). The protein and lactose content of milk samples were determined using a Dairylab 2 IR milk analyser (Foss UK Ltd, Cheshire, UK).…”

“…For full details of animal methods, refer to Capper et al (2005). Briefly, 36 twin-bearing and 12 tripletbearing ewes were allocated to one of four dietary treatments according to litter size, live weight and condition score (Russel et al, 1969).…”

“…A basal concentrate was formulated based on barley and sugar-beet pulp, details of which have been described previously (Capper et al, 2005). To this diet was added 120 g/kg of either a control fat or fish oil pre-mix and a vitamin/ mineral supplement containing either a basal (50 mg/kg) or supranutritional (500 mg/kg) concentration of vitamin E (a-tocopherol acetate; Roche UK Ltd, Heanor, Derbyshire, UK; Table 1).…”