Fast and convenient assay for quantifying total immunoglobulin levels in cattle serum and colostrum

母源抗体对于保护小牛免受大量新生儿疾病的侵害至关重要。与其他动物相比，母体的抗体转移仅限于初乳的摄取，而其他动物则能够通过胎盘转移。因此，初乳中的抗体浓度对小牛的生存和健康至关重要。乳制品生产商可以选择在农场测试和储存高质量的初乳，或者购买商业上可获得的（例如萨斯卡通初乳有限公司（SSCL））质量受控的冻干初乳。为了生产统一的初乳，SSCL需要量化所有输入初乳批次及其最终产品的IgG水平。目前，他们使用的是一种内部放射免疫扩散测定法，这种方法速度慢，劳动强度大。在本项目中，我们将采用一种新的总IgG测定法，以满足SSCL生产工艺的需要和规范。新的检测方法是基于融合到免疫球蛋白结合蛋白结构域的裂解酶。该测定法的优点是不需要冲洗步骤，并且先前已证明与RID结果具有良好的相关性。为了消除任何移液步骤，从而提高方便性和准确性，本项目的目标是1。建立与IgG定量测定兼容的基于滤纸的高通量单步初乳IgG分离方法。2.在不同的检测格式中比较和选择最实用和有效的版本。3.通过单一的大肠杆菌菌株生产所有的生物试剂。预计样品处理的减少和测试速度的提高，将使SSCL显著提高其初乳测试能力。低成本的材料，易于生产的生物试剂和thelack需要专门的设备，这将使这是一个非常便宜的测试系统。这将有助于SSCL降低生产成本，提高盈利能力和竞争力。

Maternal antibodies are crucial in the protection of calves against a large number of neonatal diseases. Maternaltransfer of antibodies is restricted to the uptake of colostrum in contrast to other animals that are capable ofplacental transfer. Consequently, the concentrations of antibodies in colostrum is essential for the survival andwell-being of the calves. Dairy producers have a choice of testing and storing high quality colostrum on farm orpurchasing commercially available (e.g. Saskatoon Colostrum Company Ltd. (SSCL)) quality controlled freezedried colostrum.To produce uniform colostrum, SSCL needs to quantify the IgG levels of all the input colostrum batches and oftheir end-product. Currently, they are using an in-house Radial Immuno Diffusion assay which is slow andlabor intensive.In this project, we will adapt a novel total IgG assay to the needs and specification of SSCL's productionprocesses. The novel assay which is based on a split enzyme fused to immunoglobulin binding proteindomains. This assay has the advantage that no rinsing steps are required and that it has been previouslydemonstrated to correlate well with RID results. To eliminate any pipetting steps and thereby increaseconvenience and accuracy, the objectives of this project are to 1. Establish high through-put single step filterpaper based colostrum IgG separation method compatible with the IgG quantification assay. 2. Compare andselect the most practical and efficient version among different assay formats. 3. Production of all bioreagentsby a single E.coli strain.The projected reduction of sample processing and increased speed of test, will allow SSCL to significantlyramp up its colostrum testing capacity. The low-cost materials, ease of production of the bio-reagents and thelack of need for specialised equipment, which will make this a very inexpensive test system. This will helpSSCL reduce the production costs and be more profitable and competitive.