The aim of this work was to compare the efficacy of different cow side tests for diagnosis of ketosis including Precision
Xtra ketone method and PortaBHB milk ketone tests in Holstein- Friesian dairy cows. The colorimetric estimation of serum
BHBA at a cut-off point ≥1.200 mmol /L was used as a gold standard method. For that purpose, 200 Holstein- Friesian dairy
cows up to 6 weeks postpartum were tested. The prevalence of ketosis was 11% by using colorimetric method. The apparent
prevalence of ketosis was 12.5% by using of Precision Xtra ketone test at a cut-off point of blood BHBA ≥1.200 mmol /L
with 90.9% sensitivity, 97.2% specificity, 80 % positive predictive value (PPV) and 98.9% negative predictive value (NPV).
A significant correlation (r = 0.871; P