Authors : Cheng Xia, Shi Shu, Bo Wang, Chuang Xu, Hong-You Zhang, Ling Wu and Jia-San Zheng
Abstract: This study assessed the effect of anionic salts in the prevention of hypocalcaemia in dairy cows. Fifty multiparous Holstein cows were randomly divided into 5 groups: Control group (C) and 4 treatment (T1-T4) groups. The T groups were fed different doses of anionic salts added to their diets from day 21 pre-calving and The Dietary Cation-Anion Difference (DCAD) was 85 mEq kg-1 DM (C), -30 mEq kg-1 DM (T1), -80 mEq kg-1 DM (T2), -130 mEq kg-1 DM (T3) and -180 mEq kg-1 DM (T4). Plasma Ca2+, Hydroxyproline (HYP), 1,25-Dihydroxyvitamin D3 (DHVD), Parathyroid Hormone (PTH) and pH were determined during the transition period. The results revealed that there was a relatively high incidence of hypocalcaemia (80%) in the C group compared with the T groups (35-65%). Furthermore, plasma concentrations of Ca2+ and HYP in the T groups were higher than those of the C group at calving (p<0.05) and plasma pH value (p<0.05) and PTH concentration (p<0.05 or p>0.05) in the T groups were lower than those of the C group at calving. These results suggest that anionic salts may induce metabolic acidosis and reduce the incidence of hypocalcaemia. Compared to all groups, cows in the T3 group had the lowest incidence of hypocalcaemia and plasma PTH concentrations (p<0.05) and the highest plasma Ca (p<0.05) and HYP (p<0.05) concentrations at calving indicating that cows fed a DCAD diet of -130 meq kg-1 DM prior to calving may efficiently activate Ca homeostatic mechanisms. In conclusion, anionic salts prior to calving may enhance Ca homeostasis and reduce the incidence of hypocalcaemia in dairy cows.
Cheng Xia, Shi Shu, Bo Wang, Chuang Xu, Hong-You Zhang, Ling Wu and Jia-San Zheng, 2013. Effects of Anionic Salts on Hypocalcaemia and Ca Homeostasis in Periparturient Dairy Cows in China. Journal of Animal and Veterinary Advances, 12: 1193-1197.