Evaluating the impact of maternal vitamin D supplementation on sow performance: II. Subsequent growth performance and carcass characteristics of growing pigs.

A of subsample of 448 growing pigs (PIC 327 × 1050) weaned from 52 sows fed varying dietary vitamin D regimens were used in a split-plot design to determine the effects of maternal and nursery dietary vitamin D on growth performance. Sows were previously administered diets containing vitamin D as vitamin D (800, 2,000, or 9,600 IU/kg) or as 25(OH)D (50 µg [or 2,000 IU vitamin D equivalent]/kg from HyD; DSM Nutritional Products, Parsippany, NJ). Once weaned, pigs were allotted to pens on the basis of previous maternal vitamin D treatment, and then pens were randomly assigned to 1 of 2 nursery vitamin D dietary regimens (2,000 IU of vitamin D/kg or 50 µg 25(OH)D/kg). Pigs remained on nursery vitamin D treatments for 35 d, and then they were provided common finishing diets until market (135 kg). Growing pig serum 25(OH)D suggested that maternal dietary vitamin D influenced ( < 0.001 at weaning) serum concentrations early after weaning, but nursery vitamin D regimen had a larger impact ( < 0.001) on d 17 and 35 postweaning. Overall growth performance was not influenced by nursery vitamin D dietary treatments. From d 0 to 35 in the nursery, pigs from sows fed increasing vitamin D had increased (quadratic, < 0.003) ADG and ADFI, but G:F was similar regardless of maternal vitamin D regimen. Also, pigs from sows fed 50 µg/kg of 25(OH)D had increased ( = 0.002) ADG compared with pigs weaned from sows fed 800 IU of vitamin D. Throughout finishing (d 35 postweaning until 135 kg), ADG was increased (quadratic, = 0.005) and G:F was improved (quadratic, = 0.049) with increasing maternal dietary vitamin D. Also, pigs from sows fed 50 µg/kg of 25(OH)D had increased ( = 0.002) ADG compared with pigs weaned from sows fed 800 IU of vitamin D. Carcass data were collected from a subsample population separate from that used for the growth performance portion of the study, and a total of 642 carcasses from progeny of sows fed the varying dietary vitamin D treatments were used. Live BW of pigs at marketing and HCW were heavier ( < 0.030) for pigs from sows previously fed 25(OH)D compared with pigs from sows fed 9,600 IU of vitamin D. Overall, pigs from sows fed 2,000 IU of vitamin D grew faster after weaning compared with pigs from sows fed 800 or 9,600 IU of vitamin D. Pigs from sows fed 25(OH)D hag greater ADG compared with pigs from sows fed 800 IU of vitamin D, and they had increased final BW and HCW compared with pigs from sows fed 9,600 IU of vitamin D.