Serosurvey Of Serology To Bovine Brucellosis In Dairy Herds And Immune Effect Of A19 Vaccine

Brucellosis is a common infectious disease of zoonosis caused by bacteria of the genus Brucella.China has classified as types Ⅱ of animal diseases.Brucella is an intracellular parasitic pathogens,mainly against the animal’s lymphatic system and reproductive system.Sick animals mainly through the flow of products,semen and milk bacteria row,which flow products is the most important source of infection.Sheep,cattle,pigs,is the strongest susceptibility animal,dairy than male livestock.Adult animals,more than the incidence of young animals.For dam,the first pregnancy dairy have the main symptoms of abortion,which make great harm.In the recent years,with the rapid development of Chinese dairy and continuous improvement of largescale and intensive level,the situation of infectious bovine brucellosis prevention and control is more and more severe.However,due to the particularity of brucellosis,the current prevention and control of the main methods are rely on quarantine and vaccination vaccination two measures.In this study,we conducted a survey and epidemiological investigation of bovine serum brucellosis in several large-scale pastures in China,and provided data support for prevention and control of brucellosis in rangeland.At the same time,we selected a large-scale pasture,The antibody titer of the A19 vaccine was tested by c-ELISA and i-ELISA,and the production data were tracked to provide the clinical validation for the immune effect of ranch A19 vaccine.1、Serological Investigation of Antibodies Against Brucellosis in Dairy CowsA total of 13 large-scale Holstein dairy cattle farms were collected from all regions of China.The serum samples were collected by c-ELISA for serology of brucellosis Detection,and rangeland of the basic production data and epidemiological investigation.A total of 6219 blood samples were detected in this trial.The results showed that the positive rate was 77.46%in all the other pastures except the four pastures in Shanghai.2、Antibody follow-up investigation of bovine immunodeficiency virus A19 vaccine after brucellosis infection in pastureIn order to study the changes of antibody and the immune effect of vaccination after immunization with A19 vaccine,60 cows aged 3 to 4 months were selected.The tiger red plate agglutination test,c-ELISA,i-3,4,5 and 6 months after immunization,and to observe the reproduction of these cattle in the later period.The results showed that all the three methods could be negative in 6 months after vaccination,and the reproduction of vaccinated cattle was normal,and there was no scale abortion,which indicated that the vaccine had a certain protective effect on the cow.