Predictive Value of Prepartum Amino Acid and Biochemical Profiles for Hypocalcemia in Holstein Dairy Cows.

Prepartum LDL, glycine, 3-methylhistidine, and hydroxylysine may predict hypocalcemia risk in transition dairy cows.

This prospective cohort study investigated the predictive utility of prepartum amino acid profiles and standard biochemical parameters for the development of hypocalcemia in transition Holstein dairy cows. Sixty cows were enrolled approximately 10 days before calving and monitored throughout the transition period. Receiver operating characteristic (ROC) analysis identified several prepartum markers with clinically meaningful predictive accuracy. LDL cholesterol demonstrated the highest predictive power at 88% (cutoff: 20.70 mg/dL), followed by glycine at 90% for periparturient changes of ≥35%, 3-methylhistidine at 85% (cutoff: 8.30 µmol/L), hydroxylysine at 82% (cutoff: 9.20 µmol/L), total bilirubin and cholesterol both at 80% (cutoffs: 0.018 mg/dL and 84.1 mg/dL, respectively), and aspartic acid at 77% (cutoff: 3.43 µmol/L). The inclusion of amino acid markers such as 3-methylhistidine—a biomarker of muscle protein catabolism—and hydroxylysine, associated with collagen turnover, suggests that altered protein metabolism plays a role in hypocalcemia pathogenesis. These findings propose that routine prepartum screening incorporating both amino acid and lipid metabolism parameters could improve early identification of at-risk cows, allowing timely prophylactic intervention. Limitations include the single-breed design and moderate sample size, which may affect generalizability. Overall, this study expands the toolkit available to large animal practitioners for transition cow health management.

This summary was distilled by AI and may occasionally misinterpret data. Confirm critical details with the primary literature before clinical application.