The Prevalence Of Sheep Hydatid Disease And Evaluation Of Vaccine Immunity In Hejing County,Xinjiang Autonomous Region

In Xinjiang,echinococcosis(hydatid disease)is a known,potentially risky zoonotic parasitic disease,which has caused serious economic losses to the healthy development of local animal husbandry and public health.At present,the immunization against sheep hydatid disease has been included in the compulsory immunization against major animal diseases and has become one of the important preventive and control measures for hydatid disease.In order to provide effective data for the prevention and control of local sheep hydatid disease,this study was conducted by ELISA,epidemiological investigation,PCR from September 2018 to November 2019 in Hejing county,Xinjiang.The prevalence of sheep hydatidosis was investigated in Hejing county.At the same time,the compulsory hydatid(hydatid)genetic engineering subunit vaccine was evaluated for the immune effect,which laid the foundation for the prevention and control of hydatid disease.The main content of the paper is as follows:1.Serological and epidemiological survey of sheep hydatid echinococcosis in Hejing County,XinjiangIn order to understand the infection and prevalence of Echinococcus granulosus in the agricultural and pastoral areas of Hejing County,540 whole blood samples of sheep and 90 fresh dog manure samples were collected from 5 townships in the agricultural area of Hejing County and 7 townships in the pastoral area.The infection and prevalence of sheep Echinococcus granulosus and sheep Echinococcus granulosus in Hejing County were investigated by ELISA.The results showed that the average infection rate of sheep Echinococcus granulosus in Hejing County was 27.2%(147/540),of which the infection rate in agricultural areas was 15.5%(35/225)and the infection rate in pastoral areas was 35.5%(112/315);The infection rate of dog Echinococcus granulosus in Hejing County was 15.5%,of which the infection rate was 6.6% in agricultural areas and 24.4% in pastoral areas.The infection rate in the pastoral area of Hejing County was much higher than that in the rural area,and the infection rate of the three towns on the Bayinbuluk grassland in the pastoral area was the highest,reaching 37.7-42.2%.2.Genotypy of Epidemic Strains of Sheep Echinococcus granulosus in Hejing County,XinjiangIn order to understand the infection status of sheep echinococcosis and the genotyping of epidemic strains in Hejing County,Xinjiang,investigations and statistics were conducted on the infection status of echinococcosis in 1115 sheep over 1 year old in Hejing County Slaughterhouse.Hydatid cysts were found on the surface of 225 sheep organs,the infection rate was 20.1%,of which the infection rate from rural areas and towns was 6.6%,and the infection rate was 25.8% in pastoral areas.The statistics of parasitic sites were that the infection rate of liver was 15.1%(169/1115),the infection rate of lung was 5%,and the infection rate of liver and lung at the same time accounted for 1.5%(17/1115).PCR amplification,cloning,sequencing and Blast comparison in NCBI using specific primers for the mitochondrial cytochrome oxidase gene 1(mt CO1)specific primers found that the genotype of the epidemic strain of sheep Echinococcus granulosus were G1 type in Hejing County,Xinjiang.3.Evaluation of genetic engineering subunit vaccine against sheep hydatid diseaseIn order to evaluate the immune efficacy of genetic engineering subunit vaccine of sheep hydatid disease,test group(vaccine)and control group(non-vaccine)of 90 sheep were tested respectively by ELISA Hejing County,Xinjiang.The larval antibody was tested by ELISA on the 28 th day after the first immunization,the 14 th day after the second immunization,and 280 days after the first immunization,respectively.At the same time,30 sheep from the control and test groups were rando m Ly selected for pathological observation.The test results showed that the antibody conversion rate of 90 sheep in the test group at 28 days after the first immunization was 84.4%,the antibody conversion rate was 97.7% on the 14nd day after the second immunization the antibody conversion rate was 94.4% at 280 days after the first immunization,respectively.The infection rate of control group was 1.1% by ELISA after 28 days,the infection rate of sheep hydatid echinococcosis was 3.3% after 42 days.the was used 42 days later The larval antibody ELISA test showed an,and the infection rate was 34.4% after 280 days..The pathogenic test results showed that the test group and the control group were rando m Ly selected on the 280 th day after the first immunization.Thirty sheep were dissected and examined for the protective effect of immunity.It was found that one sheep in the experimental group had hydatid cysts in their organs,and the infection rate was3.3%;ten sheep in the control group had hydatid cysts in their organs.The infection rate was 33.3%.In sμmmary,there is a sheep hydatid disease in Hejing County,and the infection rate in pastoral areas is much higher than that in rural areas;genetic engineering subunit vaccine of sheep hydatid(hydatid)is effective in the sheep,and the duration of immunity is longer,which can effectively protect the sheep against the infection of parasite eggs.This study provides scientific evidence for the prevention and control of sheep Echinococcus granulosus in Hejing County in the future.