Evaluation of the Diagnostic and Analytical Performance of the CentriVet Blood Ketone Monitoring System in Postpartum Dairy Cattle.

Abstract

BACKGROUND: The periparturient period in dairy cows is marked by negative energy balance (NEB), resulting in metabolic stress and an increased risk of postpartum diseases. Accurate assessment of NEB through blood &#x3b2;-hydroxybutyrate (&#x3b2;-OHB) levels is essential for effective herd management. Point-of-care (POC) devices, such as the CentriVet blood ketone monitoring system, offer a practical alternative to laboratory methods for measuring &#x3b2;-OHB. OBJECTIVE: This study aimed to evaluate the diagnostic and analytical performance of the CentriVet blood ketone monitoring system compared to a laboratory reference method for measuring blood &#x3b2;-OHB concentration in postpartum dairy cattle. METHODS: A total of 105 postpartum dairy cows from two farms were included. Blood samples were analyzed for &#x3b2;-OHB using both CentriVet and a reference enzymatic method. Passing-Bablok regression, Bland-Altman plots, and kappa statistics were used to assess agreement. Diagnostic accuracy metrics (sensitivity, specificity, PPV, NPV, and accuracy) were calculated at a cut-off value of &#x2265;&#x2009;1.2&#x2009;mmol/L. An optimized cut-off value was determined via ROC curve analysis. RESULTS: CentriVet demonstrated a moderate correlation with the reference method (Spearman's r&#x2009;=&#x2009;0.701, p&#x2009;<&#x2009;0.001). Passing-Bablok regression revealed proportional bias, and Bland-Altman analysis indicated a mean bias of -0.4&#x2009;mmol/L. Diagnostic metrics at &#x2265;&#x2009;1.2&#x2009;mmol/L showed 100% sensitivity, 68.09% specificity, and 71.4% accuracy. ROC analysis yielded an optimized cut-off of >&#x2009;1.5&#x2009;mmol/L, improving specificity (95.7%) but reducing sensitivity (81.8%). CONCLUSIONS: While CentriVet offers practical benefits, its diagnostic performance is limited for accurately identifying hyperketonemia in postpartum dairy cattle.