Determination Of IgG In Bovine Colostrum And Establishment Of Immunogold Technique Half-Quantitative Detect And Application

Bovine colostrum is the secretion form the mammary gland for the first days after parturition. Bovine colostrum is a rich source nutrients, antimicrobial factors and growth factors.Immunoglobulins are the most functional component in bovine colostrums,Bovine colostrum contains 86% IgG,It is 200 times of milk and 50 times of humankind colostrums. There was a nice pertinency between the content of IgG and the content of others activity in bovine colostrums.So prove biological activity of bovine colostrum and bovine colostrums product, the best way to detect the content of IgG in bovine colostrum and bovine colostrums product. Rabbit,s antibodies against bovine IgG was purified by DEAE-fibrin.With double immunediffusion and SDS-PAGE assay purified antibody.The result showed that activity and purification of purified antibody was preferable. Single immunediffusion method was used to determine content of IgG in bovine colostrums changing with time.the result showed that the content of IgG in bovine colostrums in seven day after parturition has large amounts changes ,the content of IgG in the range of 118.59～0.86mg/ml. The first 7 times milking after parturition is used raw material of bovine colostrums products is optimal.If the first 3d,5d or 7d milking after parturition as raw material of bovine colostrums products , quality of products will decline. The colloidal gold ,which diameter is about 20nm,is obtained by reducing the gold chloride with sodium citrate and copled with stardard bovine IgG so that the immuno-colloidal gold was obtained. The optimal pH for labelingis 9.3 and the amount of stardard bovine IgG is 24 ug/ml . 0.01mol/L PBS comprise 1% bovine serum albumin 0.02%sodium azide as stabilization of immuno-colloidal gold, it make immuno-colloidal gold be in fair preservation.The results can be read clearly in 15 minutes and it can preserve for long time.Use the Immunogold half-quantitative method and Single immunediffusion method to test 10 bovine colostrums samples and 6 bovine colostrums products samples, the result showed that there was a nice pertinency between diluted multiple of sample and tinct change of nitrocellulose membrane with labele antibody and results of Single immunediffusion method. It is unsuitable for accurate quantitative test. This method is simple,rapid and convenient tool for test the content of IgG in bovine colostrums bovine colostrums products in production. The result of detected can be visually read by eye requiring no instrumentation.So this method has comprehensive application and popularize worth.