Fig. 6

IFN-γ and IL-4 expression levels in splenocytes of SPF chickens. Spleens were isolated from chickens (n = 8) vaccinated intramuscularly at two weeks after the third inoculation, and the levels of IFN-γ and IL-4 in the spleens at 5 h post-stimulation were determined by qRT-PCR. Data are presented as the mean ± standard error of the mean. Statistical significance of differences is illustrated as follows: *P < 0.05