Finally,
we set out to evaluate if test characteristics could be
enhanced by repeating measurements after different
time intervals. During 4 herd visits, a total of 128 cows
(8 to 28 d in milk) fed 10 times daily were screened at
0900 h and preselected by BHBA concentration. Blood
samples were drawn from the tail vessels and BHBA
concentrations were measured using an electronic
BHBA meter (Precision Xceed, Abbott Diabetes Care
Ltd., Witney, UK). Cows with BHBA concentrations
≥0.8 mmol/L at this time were enrolled in the trial
(n = 92). Subsequent BHBA measurements took place
every 3 h for a total of 8 measurements during 24 h.