Effects of 25-hydroxycholecalciferol supplementation in maternal diets on milk quality and serum bone status markers of sows and bone quality of piglets.

Twenty primiparous sows were allocated to two treatments to evaluate the effects of maternal 25-hydroxycholecalciferol (25OHD3 ) supplementation during gestation and lactation on milk quality and serum bone status markers of sows and bone quality of piglets. Immediately after mating, sows were randomly allotted to one of two diets supplemented with 50 µg/kg 25OHD3 or basal diets without 25OHD3 . Blood and milk samples were obtained. At birth and weaning, 10 piglets from each treatment were killed for bone quality analysis. 25OHD3 -fed sows provided one more piglet at farrowing and 1.17 more piglets at weaning than sows fed basal diets. The contents of solids not-fat, protein, fat or lactose were increased in milk from days 7 and 14 of lactation in 25OHD3 -supplemented sows and 25OHD3 concentrations in milk were increased by dietary 25OHD3 supplementation. Dietary 25OHD3 supplementation increased serum alkaline phosphatase activity but had no effect on serum tartrate-resistant acid phosphatase activity of sows. Maternal 25OHD3 supplementation improved bone strength, density and ash content of newborn piglets rather than those of weaning piglets. In conclusion, 25OHD3 supplementation in maternal diets improved reproductive performance, milk quality and bone status of sows as well as bone quality of newborn piglets.