Abstract
The purpose of this study is to evaluate the effectiveness of metabolic and physical indicators in clinical practice that identified dairy cattle at increased risk of diseases after calving. One hundred and twenty-six Holstein cattle from a farm of Hokkaido Prefecture were used in this study. The experimental period was from October 2007 to July 2009. Blood samples were once collected in 2 to 14 days before expected calving in order to determine serum concentrations of nonesterified fatty acids (NEFA), beta-hydroxybutyrate (BHB) and apolipoprotein B-100 (apoB). The assessments of body condition score and rumen fill score were also carried out on the same time. The diseases happened within 30 days in milk were checked by a field veterinarian. Around parturition, serum NEFA concentration in heifers was significantly (P<0.01) higher than that in cows, which may suggest that the metabolic difference in both animals. However, similar findings were not observed in other metabolites. The odds of diseases were 3.2 times greater in cows with serum NEFA≥0.4mEq/L. The area under receiver operator characteristic curve in serum NEFA (0.683) was greater than those in other metabolites (BHB, 0.593 ; apoB, 0.343). In assessing the association physical monitoring and parity with the occurrence of disease in heifers and cows using multivariable logistic regression, rumen fill score was related to increased risk of subsequent disease (odds ratio=0.383). From these findings, it is suggested that serum NEFA concentration and rumen fill score before calving are effective predicators.
