Guangxi Domestic Ruminant EHD Serology And Media Investigation And Pathogen Isolation And Identification

Deer epidemic hemorrhagic fever is a Reoviridae genus Circovirus epidemic hemorrhagic fever virus (EHDV) caused by an insect-borne viral disease. Widely distributed in tropical and temperate regions.In this study, for the EHDV group-specific antigen VP7 protein design competing antibody ELISA kit, a serum sample by detecting the presence of antibodies in the VP7 which investigate infection in animals.Test sera were collected from 217 goats,313 cattle serum in total of 530, sampling includes some areas of Guangxi.Testing results showed that the territory of Guangxi ruminant animal widespread resist EHDV infection, and the positive rate of serum around difference parts which exist difference, the mean of serum positive rate was 36.2%. Among them, the positive rate of cattle was 55%, and the positive rate of goats was 9.2%.Based on serological investigation,selection low altitude, high humidity, suitable medium insect reproduction, the positive rate of EHDV serological high and cattle and sheep intensive Guangxi Mashan County which set up cattle vector borne disease monitoring point, at the end of August three consecutive days capture media Culicoides to morphological and molecular biological identify in the monitoring point which mosquito active. The identification results show that the advantage Culicoides in Guangxi monitoring points of the mosquito active period is Culicoides.oxystoma, which consistent with the reported in Japan and Southeast Asia.Screening 10 head of cattle and 5 goats as sentinel animals which EHDV antibody negative in the monitoring point, were polyculture in cattle and sheep which EHDV antibody positive, with grazing day andnight to keep the pens.1-4 monthly blood sampling time,5-12 month measured once a week.Using competitive enzyme linked immunosorbent assay (C-ELISA) method for monitoring the antibody positive conversion, take the animal red blood cell which antibody turn positive, vaccination sensitive cell to separate EHDV.Identification of isolates to RT-PCR, virus neutralization test, the results before and after the 3 sentinel animal seroconversion to a total of 8 blood samples were isolated 3 strains of virus, TCID50 respectively 10-2.5/0.1mL,10-2.83/0.1mL,10-2.5/0.1mL, serotype are identified as type EHDV-5.This is the first isolated EHDV from cattle in Guangxi, that EHDV infection existed in ruminant animal.