Evaluation and Use of Three Cowside Tests for Detection of Subclinical Ketosis in Early Postpartum Cows

作者：J. Carrier, Steven Stewart, S. Godden, John P. Fetrow, Paul Rapnicki · 发表于：Journal of Dairy Science · 年份：2004 · DOI：10.3168/jds.s0022-0302(04)73511-0 · 被引用次数：149 · 研究领域：Reproductive Physiology in Livestock、Genetic and phenotypic traits in livestock、Birth, Development, and Health

The objective was to evaluate the performance of 3 cowside diagnostic tests for detection of subclinical ketosis, defined as a serum beta-hydroxybutyrate (BHBA) concentration >or=1400 micromol/L. On 16 d over a 5-mo period, samples of serum, milk, and urine were collected on a large dairy facility from cows of all parities between 2 and 15 DIM. The sample proportion of subclinical ketosis was 7.6% (n = 859 samples from 545 cows). The KetoCheck powder (Great States Animal Health, St. Joseph, MO) detecting acetoacetate in milk samples was very specific (99%) but poorly sensitive (41%). Respective sensitivities and specificities of the Ketostix strip detecting acetoacetate in urine samples (Bayer Corporation, Elkhart, IN) were 78 and 96% with a cut-off point of "small", or 49 and 99% with a cut-off of "moderate." The KetoTest strip (Sanwa Kagaku Kenkyusho Co. Ltd., Nagoya, Japan) using milk samples had a sensitivity and specificity of 73 and 96% with a cut-off of 100 micromol of BHBA/L or 27 and 99% with a cut-off of 200 micromol of BHBA/L. On average, use of the Ketostix at the "small" cut-off point or the KetoTest at 100 micromol/L would result in no more than 3 or 4 false positives per 100 cows screened, with prevalence levels ranging from 5 to 30%, whereas the number of false negatives would range from one false negative at 5% prevalence to 7 or 8 false negatives at 30% prevalence. Either the Ketostix or KetoTest strips would provide acceptable results for screening individu...