Effect of Serum Calcium, Magnesium, and Phosphorus Levels in Cyclic and Postpartum Anestrus Jersey Cross Cows

Abstract

Mineral deficiencies and disproportion are often considered as major cause for prolonged postpartum anestrus condition in dairy cows. However, there is no clear indicator to suggest that delayed postpartum estrus is caused by inadequate mineral level for a dairy cow in Bhutan. Therefore, this study determined serum calcium, magnesium, and phosphorus levels in cyclic and postpartum anestrus Jersey cross cows and their effect on reproductive efficiency. The study was undertaken in Tsirang Dzongkhag from November to December 2013. Eighty Jersey cross cows, 40 cyclic and 40 postpartum anestrus, were sampled for the study. The mineral levels in serum samples were determined by colorimetric method in a 96 well u-bottom plate and absorbance read by microplate reader using commercial mineral kits. Data analysis was done using Statistical Packages for Social Science version 16.0. The serum calcium level was significantly higher (p < .05) in cyclic cows, which was estimated at 10.32 ± .21 mg/dl compared to 9.61 ± .16 mg/dl in postpartum anestrus cows. The serum magnesium levels did not vary significantly (p > .05) between cyclic cows and postpartum anestrus cows, which were recorded
at 1.94 ± .09 mg/dl and 1.75 ± .08 mg/dl respectively. Significantly higher (p <.05) serum phosphorus level was recorded in cycle cows, which was 7.65 ± .14 mg/dl compared to 7.27 ± .09 mg/dl in postpartum anestrus cows. The serum calcium and phosphorus ratio was higher in cyclic cows (1.35:1) compared to postpartum anestrus cows (1.32:1). The findings indicate that low levels of calcium and phosphorus in blood can influence reproductive efficiency in dairy cows.