The Study On The Molecular Diagnose And Pathogenesis Of Porcine Eperythrozoonsis

The study focused on molecular diagnose of Eperythrozoon Suis.cause of Porcine Eperythrozoonsis, the animal model and new transmit way and pathogenesis of this disease. 1.The study on molecular diagnose of Eperythrozoon Suis: The primer to diagnose Eperythrozoon Suis was designed according to the foreign report and 781bp DNA fragment was amplified from genome of E.suis from pig's blood. The DNA fragment was linked to pUC18-T easy vector and cloned to DH5a.The plasmid was identified by EcoR I /Sal I and Past I digestion. The homology between this fragment and that of E.suis published in Gene bank is 99.4 %. There isn't homology between this fragment and other sequence published in Gene bank. This DNA fragment hasn't been amplified from genome of Pasteurellosis, E.coli, Streptococcus Suis, Toxoplasm, Trichuras Ovine, babesia,Salmonellosis, Pseudorabies virus, Porcine reproductive and respiratory Syndrome Virus and SPF pig blood. The blood samples from 3 farms in which the pigs displayed the symptom of this disease and 5 health farms were test by Gimsa dye and microscope check and PCR diagnose. There aren't different between molecular diagnose and microscope check to detect E.suis.This test demonstrated that Eperythrozoon Suis presented in China and the pathogeny is the same as that reported in foreign by PCR diagnose and the pathogeny is very popular in Shandong province.2.Study on the method of diagnose by separation E.suis from erythrocyte: Before EPJL-1 was added into blood ,the erythrocytes of swine blood were deformed and looked like wave, star or saw by E.suis when the blood smears were stained by Gimsa dye and observed. The E.suis was stained as purplish red small dot around the erythrocyte. The erythrocyte was deformed and the E.suis was small black dot when it was observed under Olympus microscope. After EPJL-1 was added into blood and reacted 0.5-1 min ,the erythrocyte was regular and the surface of the erythrocyte was smooth again;moreover the E.suis didn't occurred around erythrocyte. 10 positive swine blood and 1 negative swine blood detected by PCR and microscope check were positive and negative also by separation method respectively. This separation method can separate E.suis from erythrocyte within 0.5-1 min and avoid blood lyses and the disturbance of dye particles.3.Study on the animal model and new infectant ways of E.suis. 16 male guinea pigs were separated to four groups and four guinea pigs in every group .The guinea pigs in first group were challenged by E.suis. The guinea pigs in second group lived together with the first one. The guinea pigs in third group were separated one.The forth group is contrast one. The 24 mice were separated into four groups as guinea pigs and 6 mice in every group. After challenged, most experimental guinea pig displayed clinical symptoms and all died. The all mice and contrast guinea pigs were normal and didn't die. The disease was diagnosed as Porcine Eperythrozoonsis. By this experiment the guinea pig regarded as a kind of model of Porcine Eperythrozoonsis and this disease maybe transmitted by air and contact. 4.The organ (heart,liver,spleen,lung,kiney,enteron,stomach) of pigs and guinea pigs suffered from Porcine Eperythrozoonsis were cut into 0.5cmx0.5cmx1.5cm pieces to proceed the research of pathological histology. When the slide were observed under microscope, the organ((heart,liver,spleen,lung, kiney) displayed hemorrhea, hemolysis.Enteron and stomach displayednecrosis,edema.5.Study on the disease course of E.suis typical clinical case and change of blood. The first sign of thepigs suffered from Porcine Eperythrozoonsis were high fever and skin became red, the number of whitecell increased. In the midth of disease the pig's skin became mauve, and the number of white celldecrease and the blood lyses, which caused anemia and cause rapid death. The course of disease wasabout 10 days; the fever is a kind of constant fever.6. Study on the cause of Porcine Eperythrozoonsis: The E.suis is a conditional pathogeny and low temperature, emasculation, vaccined...