Comparative evaluation of serum betahydroxybutyrate and Rothera test on milk for diagnosis of subclinical ketosis in high producing dairy cattle

The objective of the present study was comparative assessment of serum beta-hydroxy butyraye and Rothera test on milk for diagnosis of subclinical ketosis in high production dairy cattle. Serum and milk samples of 100 dairy cattle around Zarghan city were taken at 1, 2, 4, 6 and 8 weeks post parturation. Rothera test was positive in 30 samples. Considering the concentration if 1000 and 1200 µmol/L of serum betahydroxybutyrate for diagnosis of subclinical ketosis, the Rothera test was positive for 42 and 32 milk sampels. Using the concentration of 1000 µmol/L of serum betahydroxybutyrate as indication of subclinical ketosis, the sensitivity, specificity, positive predictive value and negative predictive value were 70%, 100%, 100% and 83% respectively. Considering the concentration of 1200 µmol/L of serum betahydroxybutyrate as indication of subclinical ketosis, the sensitivity, specificity, positive predictive value and negative predictive value were 94%, 100%, 100% and 97% respectively. Therfore it was concluded that the Rothera test on milk samples can be used as an easy and rapid test for diagnosis of sun clinical ketosis in cattle. The highest prevalence of subclinical ketosis in dairy cattle was at 4 weeks post parturition.