Hyperketonemia is defined as an abnormally high concentration of circulating ketone and is an indicator of excessive negative energy balance in transition dairy cows. The gold standard for diagnosing hyperketonemia is the measurement of BHBA in serum or plasma.
Accurate and user-friendly tools that facilitate cow-side measurement of BHBA concentrations are needed. However, one of the main drawbacks of the technology is the additional farm labor resources required to systematically test all animals at risk for hyperketonemia.
Flow-injection analysis and Fourier transform infrared (FTIR) spectroscopy are laboratory techniques that have been developed for use with DHI milk testing to measure concentrations of BHBA, acetone, fat and protein in milk. Flow-injection analysis is generally used to calibrate FTIR spectroscopy for BHBA and acetone measurement. However, the ability of milk ketone bodies values from flow-injection analysis to accurately diagnose hyperketonemia, as compared with whole blood or serum BHBA, has not been evaluated.
The first objective of this study was to determine the correlations between blood BHBA and milk components measured by flow-injection analysis (BHBA and acetone) and FTIR (fat and protein). The second objective was to establish threshold values for these milk components to predict hyperketonemia in dairy cows.
With the development and validation of diagnostic tests that are accurate, practical, and economical, producers should be encouraged to establish long-term systematic surveillance programs that will help with the early detection of transition-cow health problems, such as hyperketonemia. However, some limitations exist with DHI ketone testing programs, including infrequent sampling (generally on a monthly basis) and the lag time between milk sampling and receiving the test results. These limitations suggest that DHI testing should be used as a herd-level tool to monitor hyperketonemia, rather than to diagnose individual cows. Further work is needed to investigate appropriate herd-level surveillance strategies using DHI test results on ketone bodies.