The Trial on Efficacy of AI H9 Type Inactivated Vaccine Enhanced by Recombinant Chicken Interlukin-2(chIL-2)

The recombinant chIL-2 as adjuvant was used to enhance the immune efficacy of inactivated vaccine of avian influenza H9 type in the trial.New-hatched AA broilers were raised in cages in pathogen-free surroundings and divided into 7 groups.At 7 day age,chickens in vaccine control group were immunized with injecting 0.5 mL inactivated vaccine of AI H9 type into chest muscle,and the same dosage of AI H9 inactivated vaccine and different dosages of chIL-2 were respectively injected into the experimental group animals.The HA and HI assays were applied to detect the titers of antibody(Ab) after the immunization every 7 days.The results showed that the chickens in experimental groups immunized with chIL-2 could maintain high Ab titers of AI H9 type in two months,and the average Ab titers of them were higher 3.6-4.5 than that of the control group at the 10th weeks.It indicated that the recombinant chIL-2 could enhance activity of AI H9 inactivated vaccine.