Validation of a Rapid Cow-side Test for the Measurement of Blood Beta-Hydroxybutyrate in Fresh Cows

Abstract

Ketosis is an important metabolic disease in transition cows, associated with decreased milk production, impaired reproductive performance, and abomasal displacements. Cows with blood beta hydroxybutyrate (BHBA) concentrations greater than 14.4 mg/dL (1.4 mmol/L) are considered to be ketotic (Duffield et al). Producers or veterinarians may measure blood BHBA levels in individual sick cows (diagnostic purposes) or may periodically test representative groups of fresh cows to estimate the herd prevalence of ketosis (monitoring purposes). However, there are disadvantages to currently available tests. Though considered the gold standard, submitting serum samples to a veterinary diagnostic laboratory for BHBA analysis is inconvenient and expensive, and the delay in reporting does not lend itself as an individual animal diagnostic test. Conversely, and though they are inexpensive, rapid, and easy to use, available cow-side urine and milk ketone tests have been reported to have lower sensitivity and specificity (Carrier et al) and rely on visual interpretation of color change. Ideally, the industry would have an accurate, rapid, convenient, and inexpensive cow-side test to measure blood BHBA levels in cows. The objective of this study was to evaluate the accuracy of an electronic hand held BHBA meter, designed to measure blood BHBA in human diabetics, for cow-side use in dairy herds.