Department of Animal Sciences, University of Illinois, Animal Sciences Laboratory, 1207 W Gregory Drive, Urbana, IL 61801, USA; Department of Veterinary Physiology and Pharmacology, Texas A&M University, 4466 TAMU, College Station, TX 77843, USA.
Department of Animal Sciences, University of Illinois, Animal Sciences Laboratory, 1207 W Gregory Drive, Urbana, IL 61801, USA.
Domest Anim Endocrinol. 2017 Jul;60:61-66. doi: 10.1016/j.domaniend.2017.03.005. Epub 2017 Apr 5.
The measurement of progesterone (P4) and estradiol (E2) is essential for monitoring reproductive cycles and can aid in diagnosing the cause of poor reproductive performance in dairy cattle. Readily available, reproducible, accurate, non-radioactive assays are needed for the assessment of P4 and E2 in bovine serum. The gold standard for hormone assessment, radioimmunoassay (RIA), was compared with enzyme-linked immunoassay (EIA). Serum collected from various points in the estrous cycle was extracted with radiolabeled P4 (ie, H-P4; HE) and without H-P4 (CE) before being used in the assay. For the assessment of P4, there is a great degree of correlation between the RIA and EIA (adjusted R-square = 0.95; Pearson correlation coefficient (PCC) = 0.98, P < 0.001). A difference between the RIA and EIA methods was not detected for E2 concentrations (P = 0.16), but the correlation between techniques was poor (adjusted R-squared = 0.73; PCC = 0.87, P = 0.002). There was no difference in the serum extraction efficiency as measured with H-P4 as opposed to without (P = 0.94). The two methods for the measurement of serum extraction efficiency were highly correlated (adjusted R-square = 0.83; PCC = 0.92, P < 0.001). The concordance correlation coefficient (CCC) showed an excellent agreement between RIA and EIA for P4 determination (0.89) and between HE and CE methods (0.90). Although the 95% limits of agreement of the Bland-Altman plots encompassed 89% (8/9) and 92% (12/13) of the differences between methods for P4 quantification and extraction respectively, the CCC indicated an excellent agreement among them. The CCC between RIA and EIA for E2 quantification was 0.68 which corresponds with a fair agreement; however, the 95% limits of agreement of the Bland-Altman plot encompassed 100% (9/9) of differences between methods. The EIA and CE methods are comparable alternatives to the RIA and HE methods, respectively and can be used to quantify P4 and E2 for bovine serum.
孕激素（P4）和雌二醇（E2）的测定对于监测生殖周期至关重要，并且有助于诊断奶牛生殖性能不良的原因。需要易于获得、可重复、准确、非放射性的测定方法来评估牛血清中的 P4 和 E2。激素评估的金标准放射免疫测定（RIA）与酶联免疫测定（EIA）进行了比较。在进行测定之前，用放射性标记的 P4（即 H-P4；HE）和没有 H-P4（CE）从发情周期的各个点采集的血清进行提取。对于 P4 的评估，RIA 和 EIA 之间存在高度相关性（调整后的 R 平方= 0.95；皮尔逊相关系数（PCC）= 0.98，P < 0.001）。RIA 和 EIA 方法之间未检测到 E2 浓度的差异（P = 0.16），但两种技术之间的相关性很差（调整后的 R 平方= 0.73；PCC = 0.87，P = 0.002）。用 H-P4 测量的血清提取效率与不用 H-P4 时没有差异（P = 0.94）。两种血清提取效率测量方法高度相关（调整后的 R 平方= 0.83；PCC = 0.92，P < 0.001）。一致性相关系数（CCC）显示 RIA 和 EIA 之间用于测定 P4 的一致性很好（0.89），HE 和 CE 方法之间的一致性也很好（0.90）。尽管 Bland-Altman 图的 95%一致性界限分别包含了方法之间 89%（8/9）和 92%（12/13）的差异（用于定量和提取 P4），但 CCC 表明它们之间具有极好的一致性。RIA 和 EIA 之间用于 E2 定量的 CCC 为 0.68，对应于良好的一致性；然而，Bland-Altman 图的 95%一致性界限包含了方法之间 100%（9/9）的差异。EIA 和 CE 方法分别是 RIA 和 HE 方法的可比较替代方法，可用于定量牛血清中的 P4 和 E2。
