The Observation Of The Safety And Validity About Prenatal Breeders Which Vaccinated With REV Attenuated Vaccine

Avian Reticuloenendotheliosis is a type of retrovirus,it could infect a variety of poultry and wild birds. In different groups, they have different lesion performances.Such as cancer,growth retardation or immunosuppression. REV infection hazards are main the vertical transmission from breeder(Is also the origin 0f the corresponding chicken embryo polluted the vaccine)or chickling's early infection. Reticuloenendotheliosis includes acute mesh cell hyperplasia, short stature syndrome,duck infectious anemia and lymphoid tissue and other chronic hyperplasia. Generally,avians infected by REV naturally will not cause acute disease ,but in some cases it will lead to cell transformation (of the tumor cells) or cell pathological changes.Until now, domestic and foreign still had not used vaccine . In order to prevent and control in the chicken group the double infection. We isolated REV of SNV Strain from duck,and completed the molecular-cloning virus by reverse genetic manipulation techniques. The code-name is REV-C99.In order to induce the virus weeked,wo subcultured it in chick embryo fibroblast cells for 30 generations. We have developed REV the weak poisonous vaccine take advantage of the weekd virus,and had conducted the earlier period research.This research is for the purpose to the vaccine security, validity and the further research of chick's immunity protection .The result indicated ,all SPF chickens who vaccinated 1/5 dose of the vaccine(400TCID50) became antibodie-positive after 2W,and the toxicity will not have the very sweeping change 0.5,1,2,6h after diluted when lay aside in 4℃and 25℃. The pre-natal breeders were vaccinated with the REV weak poisonous ,all breeders do not produce viremia, and all of them became positive in REV specific antibody 2w after vaccination. The chicks from breeders which vaccinated with REV weak poisonous vaccine 5 months were 100% REV antibody-positive The production performance of pre-natal breeders who vaccinated with REV weak poisonous vaccine were compared with the control group, The result indicated that the vaccine do not have bad effection to production performance . We have collected 35 chick embryo from nissan open breeders who vaccinated with REV weak poisonous in the opening days of the initial 2,5,7,10,14,20,28,35,all chick embryos were preparated CEF, the result of indirect immunofluorescence assay (IFA) after subcultured 2 generations were REV negative.This show that the vaccine did not result in vertical transmission even vaccinated SPF breeders.We mixed the one day-old chick with adult chicken who vaccinated with REV weak poisonous. These chicks are still the REV antibody-negative after six weeks.Compared with the control group, antibody levels had no significant differences 4,5 week after vaccinated with NDV and AIV vaccine. It Shows that the vaccine does not exist the possibility of horizontal transmission This vaccine not only does not have the vertical infection to the performance but also not have adverse effect It does not have the possibility of transverse propagation.All chicks whose breeders were vaccinated with vaccine have maternal antibodies.The maternal antibodies could not only prevent growth retardation, immune organ atrophy owing to REV infection ,but also could prevent immune response inhibition of NDV and AIV vaccine.And there was a positive correlation between REV-specific maternal antibody levels and antibody titers to NDV and AIV after vaccination. REV in the attenuated vaccine The maternal antibodies provided by breeders who were vaccinated inoculation after 30W are still able to provide immune protection to chicks.