The period between the end of pregnancy and breastfeeding is crucial for the success of childbirth and breastfeeding. Sows with high levels of calcium in their bloodstream are less at risk of experiencing farrowing difficulties. Diets that provide a negative dietary anion cation gap (DCAD) and are supplemented with a vitamin D metabolite 25-OH-D3 (calcidiol) may increase calcium availability at calving and improve calving survival and performance. the piglets.
Method: This study evaluated the effects of DCAD, calcidiol (50 µg/kg), and parity (parity 1 or >1) and their interactions. Large White and Landrace sows (n = 328), parity 1 to 8, were randomly assigned in blocks to dietary treatments from day 103 of gestation to day 3 postpartum: 1) negative DCAD without calcidiol (-2 mEq/kg DCAD + non-CA), n = 84; 2) negative DCAD with calcidiol (-2 mEq/kg DCAD + CA), n = 84; 3) positive DCAD without calcidiol (68 mEq/kg DCAD + no CA), n = 81; and 4) DCAD positive with calcidiol (68 mEq/kg DCAD + CA), n = 79. DCAD negative diets were acidified with an anionic feed (2 kg/t) and magnesium sulfate (2 kg/t).
Results: Before farrowing, all DCAD-negative sows had a lower urine pH than all sows fed DCAD-positive. The percentage of sows with stillborn piglets was not affected by DCAD, calcidiol or parity alone, but sows fed the DCAD negative + CA diet had a 28% reduction in the probability of stillborn compared with the DCAD negative + non-CA diet and an even lower probability compared to the DCAD positive + CA diet. On day 1 postpartum, blood gases and concentrations of minerals and metabolites were consistent with feeding a DCAD-negative diet and this influenced energy metabolism, as indicated by higher concentrations of glucose, cholesterol, and osteocalcin and lower concentrations of non-esterified free fatty acids and 3-hydroxybutyrate. In the subsequent litter, total piglets born and born alive were higher for DCAD-positive diets compared to DCAD-negative diets; and there was an interaction between DCAD, calcidiol and parity.
Conclusion: The results suggest that feeding a DCAD-negative diet could influence the number of stillborn piglets, litter size and metabolic responses at farrowing.
Weaver AC, Braun TC, Braun JA, Golder HM, Block E, Lean IJ. Effects of negative dietary cation–anion difference and calcidiol supplementation in transition diets fed to sows on piglet survival, piglet weight, and sow metabolism. Journal of Animal Science. 2024; 102: skae027. https://doi.org/10.1093/jas/skae027
