Study On The Partial Character Research And Purification Of CSISV And Chiasm Neutralization Test With IBDV

Chicken stunt and immunosupression syndrome virus,(CSISV) mainly causes the suppression of stunt and immunosupression on poultry.The immunity suppression will lead to mixed and secondary infection of poultry.The stunt will low the production performance and make great loss to cultivation.Professor Liu Xing You has researched this disease deeply and proved the disease is caused by a new virus.The task will research the virus further about some character,purification,identification and neutralization test on the base of former research.1 day Roman,Hy-Line egg-laying chicken,AA broiler chicken,San-Huang chicken and cherry valley broiler duck all can fall ill after artificial infection.But there are differences on mortality,morbidity and growth suppression between egg-laying chicken,broiler chicken and broiler duck.Roman and Hy-Line egg-laying chicken start to be sick on the fifth day after artificial infection and the morbidity is highly up to 60%.Chickens start to die on the 7^th day.The peek of death appears on the 14^th day and the mortality is about 30%.AA broiler chicken start to be sick on 2^nd day after infection and the morbidity is highly up to 80%.Chicken start to die on 6^th day and the death peek appears on 14^th day.The mortality is 50%.San-Huang chicken start to be sick on 4^th day and the death peek appears on 14^th day.The mortality is 23.1%.The chickens which are infected but not died all grow slowly.The weight of infection group is less than that of control group after 20 days old.The suppression rate of Roman,Hy-Line egg-laying chicken,AA broiler chicken and San-Huang chicken are 54.31%,54.56%,35.51%and 37.3%respectively.Cherry valley broiler duck don't show obvious syndromes after infection,but they growth slowly.The weight of infection group is less 52.93%than that of control group on 28 days old.This virus can be inactivated completely by 2%formaldehyde.Ultraviolet waves can kill this virus by 20 minutes radiation.5%H₂O₂ can't inactive the virus completely.The CSISV has strong tolerance to acid and base.The critical value of PH is 2.0-11.5.The buoyant density of the virus is 1.16～1.18.SDS-PAGE electrophoresis indicates the allantoic fluid of CSISV has an extra band(A),which is about 30kDa,comparing with allantoic fluid of normal chick embryo.The protein's quantities of 3 bands between 66.2kDa～97.4kDa in the allantoic fluid of CSISV are more than that in allantoic fluid of normal chick embryo. Western-blotting proves the reaction between band A and the antibody of CSISV is positive.It means it is specific,so this protein maybe has the antigenicity.The virus is treated by the condition of PH 3 and PH 10.5 and then inoculated to chicken embryo.The aim is to get the purified virus and to make proportional antibodies.Also the purified virus is inoculated to 10 days SPF chicken embryo respectively.Then we can observe the morbidity situation and the shape of virus respectively and contrast them.The serum neutralization test prove s the purified CSISV-pH3.0,CSISV-pH10.5 and CSISV are probably the same virus.Cross neutralization test shows CSISV don't have cross neutralization reaction with IBDV, it means the antigen of the virus has no relationship with IBDV.