Studies On The Dynamic Change Of Compound Herbal IgY And Its Clinical Application In Neonatal Piglet

A Dot–ELISA has been developed for the detection of IgY against Enterotoxigenic Escherichia coli (K88,K99,987P) using ETEC fimbrial as the antigen for the first time and the capability of it's relatively large scale application was determined. The optimum conditions of Dot–ELISA was determined. The high specificity of the diaphragm which was made by dropping the antigen of ETEC to the nitrocellulose membrane (as the solid phase carrier)was shown by the specific blocking test and the cross-reaction test. By Dot–ELISA detecting antibodies to ETEC has good sensitivity and is sensitive more 16 times than agar immunodiffusion(AI). The result of IgY and compound herbal IgY's titer was 1:2560. All the result have shown that Dot–ELISA was a convenient, rapid, sensitive specific useful method for the detection IgY. At first ,it could be a based method for studying the dynamics changes of compound herbal IgY in new-born piglet. It could also be used for the sureillance of herd immunity and for the examination of immunization quality and so made provide for right proof to make rational immunity schedule. The Dynamics varieties of IgY were investigated in 25 healty neonatal piglets fed with bovine milk which were divided into 5 groups and sepertely medicated for 2 successive days with low dose compound herbal IgY (cIgYⅠ), high dose compound herbal IgY(cIgYⅡ), low dose IgY(IgYⅠ), high dose IgY (IgYⅡ);and the last group was fed only with bovine milk. Results of piglets serum by Dot–ELISA showed that the antibody titers to piglets serum reached the peak at 16h for cIgYⅠ(25.14) and 24h for IgYⅠ(25.16) respectively, then declined. About 23.2 of antibody titers in serum of both cIgYⅠand IgYⅠpiglets were remained on day 7 (168h).And the antibody titers reached the peak at 16h for cIgYⅡ(22.52) and IgYⅡ(22.57) respectively, then declined. About 21.6of antibody titers in serum of both cIgYⅡand IgYⅡpiglets were remained on day 7(168h). The present study indicated that the dynamics changes'characteristics of cIgY in new-born piglets, in comparision with IgY, were not significantly effected by additing Chinese herbal compound(P>0.05). The rate of piglets diarrhea in cIgY were lower than that of IgY piglets at same dose in general. The rate of piglets diarrhea in cIgY and IgY were lower than that of piglets using gentamicin.