Study On The Diagnostic Technique Of Equine Viral Arteritis And It's Application

Equine arteritis virus (EAV) is the pathogen of equine viral arteritis(EVA), one of the infectious diseases in equine to be exported or imported, which should be inspected by all countries. The hemagglutin inhability of equine arteritis virus Burucys strain cultured in RK-13 cell was tested with erythricytes from different animals at 4℃,room temperature and 37℃.HA was observed at all temperatures with erythrocytes of mouse and chicken but not with those of cattle, horse, rabbit, guinea pig, and goose. The HA activity was enhanced after treatment of virus material with Tween-80 and ether. HA titers of treated group were 4- and 8- fold higher than that of the untreated and the HI pattern of the treated virus were more obvious. The optimum conditions were as follows: pretreatment of virus materials with Tween-80 at a final concentration of 0.06～0.125% (V/V) for 15～60 min ,and treatment with ether at a concentration of 50% (V/V) for 5～15min in ice bath with continuous shakings. The SPF guinea pig was immunized with EAV Bucyrus strain and antiserum was obtained after 4 weeks. The results both HI and NT with antiserum and EAV had a positive correlation. 550 horse serum samples from New Zealand, Kyrgyzstan, Inner Mongolia and Xingjiang were detected with HI and NT respectively. The results demonstrated that the coincidence rate of both tests was 97.8%, and the antibody titers detected by both methods had a significant relationship. The HI titers were lower than those of NT.According to the diagnostic technique of equine viral arteritis reported by OIE, the micro-serum neutralization test to detect antibody of EAV was established in the present study. The optical conditions of equine arteritis virus replication on RK-13 and hyper immune serum of rabbit against EAV were obtained firstly, then by use of equine arteritis virus Bucyrus strain, the positive and negative antiserum against EAV the micro-serum neutralization test was established. No cross neutralization reactivity was found when the standard serum against equine infectious anemia virus was used. 9121 copies of equine serum specimens collected during the entry or exit inspection were contrastively detected by the micro-serum neutralization test and agar gel diffusion assay. There were 305 copies of serum with the neutralization antibody titer between 1:4 to 1:128 while only 68...