Mouse Model Of Eperythrozoonsis Suis And The Development PCR Detecting Method Of Mycoplasma Suis

Eperythrozoonosis is a kind of infectious disease in pigs caused by Mycoplasma Suis parasitical in porcine erythrocytes or plasma.Currently,researchers in many countries deepen researches on etiology,epidemiology and immunology of this disease,but they have not found effective methods in prevention and treatment yet.Thus,through establishing the Mycoplasma Suis animal infection model,this paper learned about this disease more deeply,and further laid the foundation for researches on prevention and treatment of eperythrozoonosis.In order to establish the PCR diagnosis method of Mycoplasma Suis,this experiment designed and composed a pair of specific primers,optimized reaction conditions,constructed recombinant plasmids,and carried out the sensitivity experiment and the specificity experiment according to Eno genetic traits of Mycoplasma Suis.Results showed that the size of the target fragment was 170bp and its homology with the GenBank login sequence was 98%.The sensitivity could be adopted to test 1.772ng/μL pathogen DNA;results of the specificity experiment:mycoplasma hyopneumoniae,pasteurella multocida,toxoplasmosis,streptococcus suis and porcine reproductive and respiratory syndrome samples showed no cross reactions.In order to establish the animal model of mice with Mycoplasma Suis and research characteristics of pathogen infection,this research designed the man-made infection experiment with differently treated mice,the infection experiment with different pathogen forms,the infection experiment with frozen pathogens,and the experiment in which mice were infected again by blood models.Besides,through the observation on pathogens with SEM,the SDS-PAGE antigen analysis and the specific gene segment sequence test in mouse models,this research pathogens in mouse models.Results showed that in man-made infection experiments with differently treated mice,the Kunming mouse group with no spleens,the Kunming mouse group with spleens and the BALB/C group could all be infected by Mycoplasma Suis.But infection situations of the Kunming mouse group with no spleens were better than those of the Kunming mouse group with spleens and the BALB/C group.In infection experiments with different forms of pathogens,both Mycoplasma Suis positive blood samples and purified Mycoplasma Suis samples could infect mice with no spleens.But infection situations of Mycoplasma Suis positive blood samples were better than those of the purified Mycoplasma Suis samples.In infection experiments with frozen pathogens,positive blood samples frozen for 6 months and purified Mycoplasma Suis samples could infect mice with spleens.But infection situations of both groups were worse than unfrozen positive blood samples.In the experiment in which mice were infected again by blood models,positive blood samples of mouse models could infect mice with no spleens again.Infection situations had no significant differences with those of positive blood samples.Through the observation on pathogens with SEM,the SDS-PAGE antigen analysis and the specific gene segment sequence test in the Kunming mouse group with no spleens,results had no differences with Mycoplasma Suis.Results showed that this research successfully established the animal model of mice with Mycoplasma Suis.Among all the treatment methods,infection effects of the Kunming mouse group with no spleens infected by positive blood samples were the best.Establishment of the PCR diagnosis method will provide tests of Mycoplasma Suis with more convenient channels.Establishment of animal models of mice will lay the foundation for researches on biological characteristics,pathogenic mechanisms,antigen preparation and vaccine development of Mycoplasma Suis.