Effects of 25(OH)D supplementation during late gestation on the serum biochemistry and reproductive performance of aged sows and newborn piglets.

The purpose of this study was to investigate the effects of diet type (normal or low Ca and P diets) and 25(OH)D supplementation (with or with not 2000 IU/kg 25(OH)D ) during late gestation on the serum biochemistry and reproductive performance of aged sows and newborn piglets. A total of 40 sows, which are at their 7th parity, were divided into four groups: control group (standard diet), low Ca group, 25(OH)D group and low Ca plus 25(OH)D group respectively (10 in each group). The blood of sows on day 100 and 114 of gestation and newborn piglets was collected for serum biochemical analyses. Results showed that the reproductive performance of sows was not influenced by diet type or 25(OH)D supplementation (p > 0.05). And the addition of 25(OH)D to diet low Ca group caused that the content of serum TG in sows on day 100 of gestation was not different from that of the control group (p > 0.05). The addition of 25(OH)D significantly decreases the content of serum TG in sows on day 114 of gestation (p < 0.05). The addition of 25(OH)D significantly increased the content of serum UREA and CREA in newborn piglets (p < 0.05). Overall, feeding 2000 IU/kg 25(OH)D to aged sows at late gestation had no effects on reproductive performance, but partly contributed to keeping serum TG balance in sows and may indicate increased pressure on kidneys in newborn piglets.