Correlation between Blood Biochemical Metabolites Milk Yield, Dry Matter Intake and Energy Balance in Dairy Cows during Early and Mid Lactation

摘要

The objective of the present study was to investigate nutritional and metabolic status in Simmental cows during early and mid-lactation. Fifteen early lactation cows and 15 mid lactation cows were chosen for the analysis. Blood samples were collected to measure beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), triglycerides (TG), glucose and the activity of aspartate transaminase (AST). Blood metabolites, milk yield, dry matter intake (DMI) and energy balance (EB) were recorded. Correlation analysis showed that DMI was significantly negatively correlated with NEFA, BHB and AST, and positively with glucose and TG. EB was significantly negatively correlated with NEFA, BHB and AST, and positively with glucose. Early lactation as compared to mid lactation cows were found to have significantly higher blood serum concentrations of NEFA, BHB and AST activities and lower blood serum concentrations of glucose and TG, but not significant. These metabolic changes were in correlation with DMI and EB, but not with milk yield. Suggest that they can serve as useful indicators of the nutritional and metabolic status of dairy cows during lactation.