Effect of vitamin E sources (RRR- or all-rac-α-tocopheryl acetate) and levels on sow reproductive performance, serum, tissue, and milk α-tocopherol contents over a five-parity period, and the effects on the progeny

Two dietary sources of vitamin E (DL-α-tocopheryl acetate [DL-α-TAc], or D-α-tocopheryl acetate [D-α-TAc]) at two dietary supplemental levels (30 vs 60 IU/kg) were evaluated in reproducing sows over a five-parity period. The experiment was a 2 × 2 factorial arrangement of treatments conducted as a randomized complete block in two replicates. A total of 48 gilts were fed their treatment diets from 40 kg BW through five parities, reflecting a total of 171 farrowings. Reproductive measurements of litter size, sow weight, and backfat thickness were collected. The incidence of mastitismetritis-agalactia (MMA) and fluid discharge from the vagina were evaluated for each sow on each of the first 3 d postpartum. Sows were bled at periodic intervals during gestation and at weaning (21 d) and serum was frozen. After the fifth parity, two to four sows from each treatment group were killed and tissues collected. At birth, two to three neonatal pigs were killed from each sow treatment group within each parity and livers were collected and frozen. In addition, three pigs from each litter from three to four sows per treatment group within each parity were bled at weaning and serum was saved. Six pigs from each sow group at weaning of Parity 5 were also killed and livers were collected and frozen. Sow and pig sera and tissues were analyzed for α-tocopherol. There was no effect (P >.15) of vitamin E source or level on the various sow reproductive measurements, litter size, or the incidences of MMA or fluid discharges from the vagina. Feeding D-α-TAc compared with DL-α-TAc or 60 IU compared with 30 IU vitamin E/kg diet resulted in higher (P .15) for the various α-tocopherol measurements. Although the supplemental vitamin E sources were provided on an equivalent IU basis, these results suggest that D-α-TAc has a higher equivalency than DL-α-TAc on an IU basis, but higher dietary levels also resulted in higher sow and pig α-tocopherol contents.