Immune Efficacy Of Newcastle Disease Combining With Artificial Active Immunity And Artificial Passive Immunity

Newcastle disease caused by Newcastle disease virus is an acute and highly contagious disease of fowl.It seriously threaten the development of poultry industry for its acute occurrence and high lethality.At present,this disease is generally prevailing on every area in our country.It became the most important virus disease of fowl for its epidemicity and hazard.At present the main preventive and cure measures of this disease is vaccination and high immune serum.This experiment detect the time,quantity and change regularity of Newcastle disease antibody in the organism with hemagglutination inhibition test and ELISA in different immune mode,and the change regularity of chickens antibody was studied and comparied.In the experiment,the test object is 175 healthy one-day-old hy-lying fowl after health examination,gathered the blood samples and seperate serum,then detected the titer of maternal antibody,definite the immune time is at fifteen-day-old.Randomly group 7 at fifteen-day-age,with 25 chickens in each group.Then the chickens were immunized,chickens of the first group were subcutaneously injected the oil adjuvant vaccination against Newcastle disease and highly-immunized egg yolk antibody in different parts of the body at the same time.The chickens of the second group were subcutaneously injected the New castle disease vaccinationⅣand highly-immunized egg yolk antibody in different parts of the body at the same time.The chickens of the third group were subcutaneously injected highly-minnunized egg yolk antibody,7 days later,injected New castle disease vaccinationⅣ.The chickens of the fourth group were subcutaneously injected New castle disease vaccinationⅣ.The chickens of the fifth group were subcutaneously injected highly-immunized egg yolk antibody.The chickens of the sixth group were subcutaneously injected oil adjuvant vaccination.The seventh group were blank control group,the chickens of this group were subcutaneously injected sterilized saline water.Randomly select 8 chickens in every group on the 1st,2nd,3rd,4th,7th,10th,14th,17th,21st and 28th day after immunization.Blood sampling then separate serum.Detect the titer of antibody with HI and ELISA.The result of experiment as follows:The chickens of the first group were subcutaneously injected the oil adjuvant vaccination against New castle disease and highly-immunized egg yolk antibody in different parts of the body at the same time,its titer of antibody equal to the superposition of the fifth group and the sixth group.The chickens of the second group were subcutaneously injected the New castle disease vaccinationⅣand highly-immunized egg yolk antibody in different parts of the body at the same time.The titer of antibody was not changed on the first day after immunization.The titer of antibody equaled to that which was not injected.The heightened of titer of antibody occurred on the 3th day after immunation.Then the titer of antibody equaled to the 4th group.The titer of antibody in the 3th group was samilar to the superposition of the 4th group and the 5th group.In the whole experiment,it was significantly different that the result of the 1st group and the 2nd group(P＜0.01),and it was not significantly different that the result of the 2nd group and the 3th group(P＞0.05).It was not significantly different that the result of the result of the 1st group and the 3th group(P＞0.05).The result of ELISA test was consistent with HI test in the rule of antibody change.The result of detecting serum of the same group with HI and ELISA was as follows:the general regression equation is ELISA=0.0867×HI+0.1118(R~2=0.9495).The result showed that there was a negative phase of antibody combined immunized with attenuated vaccineⅣagainst Newcastle disease and highly-immunized egg yolk antibody and there was no negative phase in the group immunized with inactivated adjuvant vaccine and Newcastle disease highly-immunized egg yolk antibody.Therefore,in order to achieve the double purpose of treatment and urgent prevention we can apply the combined immunization with the inactivated adjuvant vaccine and highly-immunized egg yolk antibody when occur the Newcastle disease,or inject highly-immunized egg yolk antibody firstly then inject attenuated vaccineⅣagainst Newcastle disease 7 days later,the combined immunization with attenuated vaccineⅣand highly-immunized egg yolk antibody was inadvisable.But the second method was time-consuming and need great efforts injecting again.