比较不同方法测定新生驹初乳 IgG 吸收的效果。

Comparison of Different Methods to Determine the Absorption of Colostral IgG in Newborn Foals.

机构信息

Clinic of Obstetrics, Gynecology and Andrology of Large and Small Animals with Ambulatory Service, Faculty of Veterinary Medicine, Justus-Liebig-University, Giessen, Germany.

出版信息

J Equine Vet Sci. 2022 Jul;114:104008. doi: 10.1016/j.jevs.2022.104008. Epub 2022 May 14.

DOI:10.1016/j.jevs.2022.104008

PMID:35577108

Abstract

The timely diagnosis of abnormalities in the passive transfer of colostral immunoglobulins is important for the health and development of newborn foals. This study investigated three different methods for measuring immunoglobulin G concentration in neonatal foals. Comparison of a commercial SNAP assay, total protein concentration determination, and total globulin calculation by subtracting the albumin fraction from total protein as an indirect parameter was performed on a quantitative ELISA, which served as a reference method. The study included 119 samples from 148 foals between the age of 1 and 6 days. A blood concentration of 800 mg/dL was considered to indicate adequate absorption of immunoglobulins, and a concentration of less than 400 mg/dL was considered to be hypogammaglobulinemia. The sensitivity of the SNAP test was 64.5% and specificity was 94.7% for diagnosing sufficient absorption of immunoglobulin G at a value of 800 mg/dL. A value of 54 g/L was found to be most appropriate for the use of total protein and provided a sensitivity of 67.3% and specificity of 84.2%. For total globulins, the most appropriate value was 27 g/L, which yielded a sensitivity of 74.5% and specificity of 81.6%. At values under 400 mg/dL, the sensitivity of the SNAP test was 89.4% and the specificity was 83.0%. Here, the most suitable value for the total protein was 51 g/L. This provides a sensitivity of 65.2% and a specificity of 76.8%. The most suitable concentration for the use of total globulin was determined to be 24 g/L, which provided a sensitivity of 75.8% and a specificity of 78.1%. The study and its results show that the SNAP test, the TP, and the TP-A method perform similarly well compared to the ELISA in determining IgG concentration of ≥800 mg/dL. Based on the 95% confidence intervals, however, the Snap test and the TP-A method appear to perform similarly well but better than the TP approach for IgG concentrations <400 mg/dL.

摘要

被动传递初乳免疫球蛋白异常的及时诊断对新生驹的健康和发育很重要。本研究调查了三种不同的方法来测量新生驹的免疫球蛋白 G 浓度。在定量 ELISA 中，比较了商业 SNAP 测定法、总蛋白浓度测定法和通过从总蛋白中减去白蛋白部分来计算总球蛋白作为间接参数的方法。该研究包括 148 匹驹 1 至 6 天龄的 119 个样本。血液浓度 800mg/dL 被认为是免疫球蛋白吸收充足的指标，而浓度低于 400mg/dL 被认为是低丙种球蛋白血症。SNAP 试验的灵敏度为 64.5%，特异性为 94.7%，用于诊断 800mg/dL 时 IgG 吸收充足。发现总蛋白的 54g/L 是最适合的，其灵敏度为 67.3%，特异性为 84.2%。对于总球蛋白，最适合的数值为 27g/L，其灵敏度为 74.5%，特异性为 81.6%。在低于 400mg/dL 的值时，SNAP 试验的灵敏度为 89.4%，特异性为 83.0%。在这里，总蛋白最适合的数值是 51g/L。其灵敏度为 65.2%，特异性为 76.8%。总球蛋白最适合的浓度为 24g/L，其灵敏度为 75.8%，特异性为 78.1%。该研究及其结果表明，与 ELISA 相比，SNAP 试验、总蛋白和总蛋白-A 方法在确定 IgG 浓度≥800mg/dL 时性能相似。然而，基于 95%置信区间，SNAP 试验和总蛋白-A 方法似乎与总蛋白方法性能相似，但对于 IgG 浓度<400mg/dL，其性能优于总蛋白方法。