Abstract：
The aim of this study was to determine and compare the diagnostic accuracy of two pregnancy-associated glycoproteins tests (IDEXX on-farm pregnancy test [OFPT] and IDEXX rapid visual pregnancy test [RVPT]) for early pregnancy diagnosis in dairy cattle. Blood samples were collected from Holstein cows (n = 317) by coccygeal venipuncture 28-31 days after artificial insemination (AI). The OFPT and RVPT were performed on the farm within 2 h after blood collection using whole blood or blood serum. Transrectal ultrasonography (USG) was performed for pregnancy diagnosis on day 32 post-AI as a gold standard. One-hundred fourteen cows were diagnosed as pregnant and 203 were determined to be nonpregnant. Furthermore, embryonic mortality was detected in four of the nonpregnant animals, based on fragmented/dispersed embryonic membranes and the absence of heartbeat. Sixteen and 14 false positive results (13 jointly for both tests) were obtained for the RVPT and OFPT, respectively. Three false negative results were obtained for the RVPT. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for the OFPT were 100%, 93.1%, 89.1%, 100% and 95.6%, and for RVPT were 97.4%, 92.1%, 87.4%, 98.4% and 94.0%, respectively. The ability of both tests to distinguish between pregnant and open cows was very good (AUC of both tests above 0.9). The OFPT and RVPT almost perfectly agreed with each other. According to McNemar\'s analysis, false positive results have been caused difference between the two pregnancy tests and USG. In conclusion, both the RVPT and OFPT proved to be reliable and practical methods for pregnancy diagnosis 28-31 days after AI in dairy cows. However, the results of both pregnancy tests were affected by the occurrence of embryonic mortality around the time of their employment.
摘要：
这项研究的目的是确定和比较两种与妊娠相关的糖蛋白测试（IDEXX农场妊娠测试[OFPT]和IDEXX快速视觉妊娠测试[RVPT]）在奶牛早期妊娠诊断中的诊断准确性。在人工授精（AI）后28-31天，通过尾静脉穿刺从荷斯坦奶牛（n=317）收集血液样品。使用全血或血清在血液采集后2小时内在农场进行OFPT和RVPT。在AI后第32天进行经直肠超声检查以诊断妊娠作为金标准。114头母牛被诊断为怀孕，其中203头被确定为未怀孕。此外，在四只未怀孕的动物中检测到胚胎死亡率，基于破碎/分散的胚胎膜和没有心跳。对于RVPT和OFPT，获得了16和14个假阳性结果（两项测试共13个），分别。对于RVPT获得三个假阴性结果。敏感性,特异性，正预测值，OFPT的阴性预测值和准确性为100%，93.1%,89.1%,100%和95.6%,RVPT为97.4%，92.1%,87.4%,98.4%和94.0%，分别。两种测试区分妊娠母牛和开放母牛的能力非常好(两种测试的AUC均高于0.9)。OFPT和RVPT几乎完全一致。根据McNemar的分析,假阳性结果是导致两次妊娠试验和USG之间的差异。总之,RVPT和OFPT都被证明是奶牛AI后28-31天妊娠诊断的可靠和实用的方法。然而,两项妊娠试验的结果都受到其就业前后胚胎死亡率的影响.
