Cloning And Analytical Comparison Of The Internal Transcribed Spacer (ITS-1,ITS-2) Sequences Of Different Eimeria Species And Strains From Chickens

Poultry coccidiosis, resulting from intracellular protozoan parasites of the genus Eimeria, is much too disastrous to stock raising, and has caused great economic loss. So far, traditional methods of the classification and identification mainly rely on, oocyst and sporangial morphology, the locations, the shortest latent and spore, and the pathopolity. With the development of molecular biology technology, the sequence analysis to some species specificity some segment of DNA by PCR, starts a new era for parasites classification. Internal transcribed spacers are ideal genetic marks, which are widely used for parasites classification and identification cross species.This research successfully obtains a pure strain from the field which preliminarily is identified to be the Eimeria praecox by the single oogonium separation technology .This thesis is the first time to do research through PCR extension, clone, measuring and sequence analysis on ITS-1 and ITS-2 of E.acervulina,E.maxima,E.mitis and Eimeria tenella 4 kinds-10 strains in all Phylogenetic analysis of the first internal transcribed spacer 1 (ITS-1) region and the second internal transcribed spacer 2(ITS-2) . The result shows that the homology of ITS of the 7 strains of E.acervulina,E.maxima,E.mitis and Eimeria tenella with the ITS which others reported is up to the 98% around, there are only 6-10 bases different from each other. There are obvious differences of the homology and size of ITS among species, so we can identify the 4 species, mentioned above, with the differences of ITS-1,ITS-2. In addition, there still exists the difference of the fragment size and the sequence homology concerning the ITS sequence of inter-species, thus it is possible to adopt some certain methods together with these differences to identify and classify the biological insect.The above work enriches the heredity information for the chicken coccidian's spacer, and has its due value in the following fields: the species identification, the epidemiology investigation of coccidian, the correct formulation preventing and controlling plan regarding the accurate appraisal coccidian , the effective prevention and treatment as for the coccidiosis. This research work is profound both theoretically and economically...