Predicting calcium status in early lactation multiparous Holsteins using milk constituent analysis

Abstract

Due to the unique challenges of supporting milk production, subclinical hypocalcemia (SCH) is common among early lacta­tion dairy cows. Though SCH immediately following parturi­tion may constitute normal adaptation to the transition period, there is growing evidence that cows with SCH beyond 4 days postpartum (DIM) have developed dyscalcemia, a pattern of calcium dysregulation that has been associated with negative health and production outcomes. Despite prevalence of dyscal­cemia ranging from 25% to 45%, identifying cows with dyscal­cemia remains a major challenge on commercial dairies. Our objective was to develop an algorithm for predicting dyscalce­mia status using Fourier-transform mid-infrared spectroscopic (FT MIR) analysis of milk samples at 3 and 4 DIM.