David J Wilson and Gregory M Goodell
Beta-hydroxybutyrate (BHB) is a ketone measured in blood or milk of dairy cattle after calving for detection of ketosis. Blood test strips, milk test strips, DHIA milk meter collected samples and hand stripped milk samples, both latter milks tested with Fossomatic analyzer, were compared for BHB measurement. Blood and milk samples were collected on the same day from 446 Holstein cows between 1–14 DIM in 5 herds for BHB testing as described above. Most test methods had continuous results but one (milk strip) had categorical results (ranges of μmol BHB /L); analysis compared whether or not each pair of BHB tests categorized the same cows as ketotic or non-ketotic (concordant, C) or disagreed on their status (discordant, D). Blood strips detected 53 ketotic (K) (≥ 1200 μmol BHB/L), 393 non-ketotic (N); milk strips detected 34 K (≥ 200 μmol BHB/L category on strip), 408 N; milk meter Foss detected 29 K (≥ 200 μmol/L), 399 N; stripped milk Foss detected 41 K (≥ 200 μmol/L), 297 N. Test comparisons: blood/milk strips 15 K/K, 371 N/N (87% C), 37 K/N, 19 N/K (13% D); blood/milk meter Foss 10 K/K, 357 N/N (86% C), 42 K/N, 19 N/K (14% D); blood/stripped milk Foss 10 K/K, 266 N/N (82% C), 31 K/N, 31 N/K (18% D); milk strips/ milk meter Foss 7 K/K, 372 N/N (89% C), 27 K/N, 22 N/K (11% D); milk strips/stripped milk Foss 16 K/K, 287 N/N (90% C), 10 K/N, 25 N/K (10% D); milk meter Foss/stripped milk Foss 5 K/K, 272 N/N (84% C), 20 K/N, 33 N/K (16% D). Results show that the BHB test methods agreed well for most non-ketotic cows, but tests did not agree well on classification of ketotic cows. Calibration improvements are a priority for improved Fossomatic testing of BHB in milk.
Teile diesen Artikel