Β-hydroxybutyrate, Glucose, Calcium, Phosphorus, and Vitamin C Concentrations in Blood of Dairy Cows with Subclinical Ketosis during the Early Lactation

The objective of this study was to examine the association between β-hydroxybutyrate (BHBA) and glucose, calcium (Ca), phosphorus (P), and vitamin C concentrations in dairy healthy and with subclinical ketosis cows during an early lactation period. The blood from 99 healthy cows and 26 sub-clinically ketotic cows within the first two months of lactation was sampled. Serum concentration of BHBA was measured by enzymatic-rate method, glucose by oxidase method, and P by colorimetric method. These tests were performed in a biochemical auto-analyser. Serum Ca concentration was measured by atomic absorption spectrometer followed by acid digestion. Vitamin C was measured by HPLC. The results showed that in ketotic cows serum BHBA was significantly increased (P<0.01) and glucose and Ca concentrations were significantly decreased (P<0.01) as compared to healthy cows, while vitamin C and P concentrations were similar in the both groups of cows (P>0.05). The serum BHBA concentration was negatively correlated with the serum glucose and Ca concentrations (P<0.01). Vitamin C and P status of cows with subclinical ketosis was not affected by BHBA. Serum Ca concentration can be used as a reference index for the diagnosis of subclinical ketosis.