A total of 84 sows (PIC 1050) and their litters were used to determine the effects of supplementing high levels of dietary maternal vitamin D3 on sow and pig performance, serum 25-hydroxy-vitamin D3 [25(OH)D3], milk vitamin D3, neonatal bone mineralisation and neonatal tissue vitamin D3.

After breeding, sows were randomly assigned to one of three dietary vitamin D3 treatments (680, 1,360 or 2,720IU per lb of complete diets). Sows were bled on days 0 and 100 of gestation, and at farrowing and weaning (day 21). Piglet bodyweight was recorded at birth and weaning, and serum was collected from two pigs per litter at birth, on day 10 and at weaning. A total of 54 piglets (18 per treatment) were euthanised at birth and necropsied to sample bones and tissues.

Sow and suckling pig performance and neonatal bone ash and bone density did not differ (P>0.10) among maternal vitamin D3 treatments but sow serum 25(OH)D3 and milk vitamin D3 increased (linear; P<0.01) with increasing maternal vitamin D3 supplementation.

Piglet serum 25(OH)D3 increased (quadratic; P<0.03) with increased maternal vitamin D3. Neonatal kidney vitamin D3 tended (quadratic, P=0.08) to decrease with increasing maternal vitamin D3 but liver vitamin D3 tended (linear; P=0.09) to increase with increasing maternal vitamin D3; however, physiological concentrations of vitamin D within these tissues were low regardless of statistical tendencies.

At weaning, a sub-sample of 180 pigs (PIC 327 × 1050) were used in a 3×2 split plot design for 35 days to determine the effects of maternal vitamin D3 and two levels of dietary vitamin D3 (816 or 8,160IU per lb) from days 0 to 10 post-weaning on piglet growth and serum 25(OH)D3.

Overall (days 0 to 35), nursery average daily gain and feed to gain ratio were not affected by either source of vitamin D3 but average daily feed intake tended (quadratic; P<0.06) to decrease with increasing maternal vitamin D3 because pigs from sows fed 1,360 IU of vitamin D3 per lb had lower average daily feed intakes than pigs from sows fed 680 or 2,720IU vitamin D3 per lb.

Nursery pig serum 25(OH)D3 increased (linear; P<0.01) with increasing maternal vitamin D3 on day 0 (weaning), and maternal × diet interactions (P<0.01) were observed on days 10 and 21 because pigs from sows fed 680IU vitamin D3 per lb had greater increases in serum 25(OH)D3 when fed 8,160IU vitamin D3 per lb than pigs from sows fed 1,360IU vitamin D3 per lb.

Flohr and co-authors concluded that sow and pig serum 25(OH)D3 and milk vitamin D3 can be increased by increasing maternal vitamin D3, and nursery pig serum 25(OH)D3 can be increased by increasing dietary vitamin D3.

They added, however, that sow and pig performance and neonatal bone mineralisation were not influenced by increasing vitamin D3 dietary levels.

Reference

Flohr J.R., M.D. Tokach, S.S. Dritz, J.M. DeRouchey, J.L. Nelssen and J.R. Bergstrom. 2013. Evaluation of the effects of added vitamin D3 in maternal diets on sow and pig performance. Proceedings of 2013 Kansas Swine Day, p1-15.

January 2014