Relationship between laboratory parameters around calving and the incidence of periparturient clinical diseases of dairy cows

The objective of this study was to measure the blood parameters [aspartate aminotransferase (AST), glutamate dehydrogenase (GLDH), albumin (ALB), total protein (TP), sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), anorganic phosphorus (P), iron (Fe), iron binding capacity (TVK), urea (KARB), beta-hydroxybutyrate (BHB), nonesterified fatty acids (NEFA)] characterizing energy and metabolic processes, of 183 dairy cows, in the period before and after calving (1, 2-3, and 4-5 weeks); and to analyse any changes in these parameters between those cows which became clinically ill, irrespective of type of illness and those which remained healthy, post-partum. Concerning these parameters for the healthy and the clinically ill cows, at each time interval the only significant (p<0.05) differences occurred with Ca in the first week, and ALB in weeks 2-3 and 4-5 after calving. Comparing to the physiological baselines at 1 week before calving, only the NEFA values for both groups and the AST values for the clinically ill group were significantly above the baselines. During the period from one week before to one week after calving the Ca, P and Fe values decreased, while the AST and NEFA values increased significantly. At one week after calving, the above changes due to calving, resulted in the P and Fe values for both groups and the Ca values for the healthy group, not differing significantly but the AST, BHB, and NEFA values for both groups, and the Ca values for the clinically ill group, differing significantly from the physiological baselines.