نوع مقاله : مقاله پژوهشی
نویسندگان
گروه آسیبشناسی، دانشکده دامپزشکی، دانشگاه القاسم الخضراء، بابل 51013، عراق
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Objective
Infectious bursal disease virus (IBDV) is an important viral pathogen of broiler chickens because of its tropism for immature B lymphocytes in the bursa of Fabricius and its potential to cause immunosuppression. The current study compared the initial immune responses created by 4 commercially available IBD vaccines in broiler chickens through stimulation of both serological and cytokine responses.
Materials and methods
A total of 250 one-day-old Ross 308 broiler chicks were randomly divided into 5 groups of 50 birds and allocated into their respective treatment received one of four types of commercial vaccine (G1-G4) and the control (G5) (Didn't receive vaccine). The antibody response of the immune system was assessed using indirect ELISA on day 1, 10, 15, 20 and 25. Quantitative RT-PCR (qRT-PCR) was performed on days 1-25 to measure the relative expression of IL-1 beta and IFN-gamma. In addition, the field isolate used (used in challenge study) was identified as containing IBDV by conventional RT-PCR targeting VP2.
Results
The maternal antibody titers for each group are similar at 1 day old. At 10 and 15 days of age, Group 1 had the highest antibody titer with the initial humoral response at those times and approached the highest final titer at 25 days. Both Groups 2 and 3 had an intermediate antibody titer at 20 days of age greater than that of Group 1. The expression levels of IL-1β did not vary significantly between groups but Group 1 had the greatest fold increase as measured by the number of individuals who were part of the analysis. Conversely, the level of IFN-γ expression was significantly different between groups. To summarize, the commercial IBD vaccine candidates examined differed in the timing and the intensity of their resultant immune responses. Of the 3 groups, Group 1 had the most favorable early immunogenicity profile by inducing earlier humoral antibody development, a stronger expression of IFN-γ, and the highest final IgY titer.
Conclusion
The findings suggest the use of integrated immune kinetics could be used as a means to generate comparative immunogenicity data of IBD vaccines in broiler chicken populations.
کلیدواژهها [English]