Pohl A, Burfeind O, Heuwieser W
Clinic of Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Königsweg 65, 14163 Berlin, Germany.
Clinic of Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Königsweg 65, 14163 Berlin, Germany.
J Dairy Sci. 2015 Jul;98(7):4544-51. doi: 10.3168/jds.2014-9181. Epub 2015 Apr 23.
Measurement of serum haptoglobin (Hapto) concentrations results in only moderate reported specificity and sensitivity for the detection of metritic cows. The objective of this study was to evaluate associations between different variables and haptoglobin concentrations after calving. Parity, periparturient metabolic stress indicated by β-hydroxybutyric acid (BHBA) and nonesterified fatty acids (NEFA), calving difficulties, retained fetal membranes (RFM), and acute puerperal metritis (APM) were evaluated. A total of 443 Holstein Friesian cows were enrolled in this retrospective observational study. Acute puerperal metritis was diagnosed when a cow had fetid, reddish-brown, watery vaginal discharge in combination with rectal temperature ≥39.5°C. The retention of the fetal membranes has been defined as the failure to expel the fetal membranes within 12h after calving. Results of blood samples from 2 and 5 d in milk (DIM) were analyzed for Hapto, BHBA, and NEFA. Primiparous cows had a greater median Hapto concentration than multiparous cows at 5 DIM [primiparous: 2.25g/L, interquartile range (IQR) 1.45-2.50, n=146; multiparous: 1.13g/L, IQR 0.52-2.22, n=302; P<0.05]. Therefore, different Hapto thresholds based on references from literature for all cows (1.4g/L), primiparous cows (2.49g/L), and multiparous cows (1.4g/L) were used for further analysis. Periparturient metabolic stress indicated by elevated BHBA (≥1.2mmol/L) at 5 DIM was associated with elevated Hapto (odds ratio 2.39-2.87) regardless of parity. In contrast, elevated NEFA (≥0.6mmol/L) at 2 DIM was not a risk factor for elevated Hapto. Multiparous cows with assisted calving had a 2.46 times higher risk for elevated Hapto, whereas primiparous cows with assisted calving had no elevated risk for elevated Hapto at 5 DIM. Moreover, multiparous cows with RFM were 5.51 times more likely to have elevated Hapto at 5 DIM than cows without RFM. Acute puerperal metritis within the first 5 DIM was associated with elevated Hapto (odds ratio 2.74-5.01), regardless of parity. We speculate that the association of calving ease, RFM, and periparturient metabolic stress could explain the moderate sensitivity and specificity reported for the detection of metritic cows by measuring Hapto.
血清触珠蛋白（Hapto）浓度的测定对于检测患子宫内膜炎的奶牛而言，所报告的特异性和敏感性仅为中等水平。本研究的目的是评估产犊后不同变量与触珠蛋白浓度之间的关联。评估了胎次、由β-羟基丁酸（BHBA）和非酯化脂肪酸（NEFA）所表明的围产期代谢应激、产犊困难、胎膜滞留（RFM）以及急性产后子宫内膜炎（APM）。共有443头荷斯坦弗里生奶牛纳入了这项回顾性观察研究。当奶牛出现有恶臭、红棕色、水样阴道分泌物且直肠温度≥39.5°C时，诊断为急性产后子宫内膜炎。胎膜滞留被定义为产犊后12小时内未能排出胎膜。分析了产后2天和5天牛奶（DIM）中的血样，以检测触珠蛋白、BHBA和NEFA。初产奶牛在产后5天的触珠蛋白浓度中位数高于经产奶牛[初产奶牛：2.25g/L，四分位间距（IQR）1.45 - 2.50，n = 146；经产奶牛：1.13g/L，IQR 0.52 - 2.22，n = 302；P < 0.05]。因此，基于文献参考，针对所有奶牛（1.4g/L）、初产奶牛（2.49g/L）和经产奶牛（1.4g/L）使用了不同的触珠蛋白阈值进行进一步分析。产后5天由升高的BHBA（≥1.2mmol/L）所表明的围产期代谢应激与触珠蛋白升高相关（优势比2.39 - 2.87），与胎次无关。相比之下，产后2天升高的NEFA（≥0.6mmol/L）不是触珠蛋白升高的风险因素。经助产的经产奶牛触珠蛋白升高的风险比高出2.46倍，而初产奶牛在产后5天经助产时触珠蛋白升高的风险并未增加。此外，有胎膜滞留的经产奶牛在产后5天触珠蛋白升高的可能性比无胎膜滞留的奶牛高5.51倍。产后前5天的急性产后子宫内膜炎与触珠蛋白升高相关（优势比2.74 - 5.01），与胎次无关。我们推测，产犊难易程度、胎膜滞留和围产期代谢应激之间的关联可以解释通过测量触珠蛋白来检测患子宫内膜炎奶牛时所报告的中等敏感性和特异性。
