Figure  5From: Pathogenic characteristics of a QX-like infectious bronchitis virus strain SD in chickens exposed at different ages and protective efficacy of combining live homologous and heterologous vaccinationBody weight of birds from the different groups at 0 and 14 days post-inoculation (dpi). A Group 1, chickens were infected with 106.0 EID50 of IBV strain SD at 2-weeks old. B Group 2, chickens were infected with 106.0 EID50 of IBV strain SD at 3-weeks old. C Group 3, chickens were infected with 106.0 EID50 of IBV strain SD at 8-weeks old. D Group 4, chickens were infected with 106.0 EID50 of IBV strain SD at 18-weeks old. E Group 5, chickens were infected with 106.0 EID50 of IBV strain SD at 22-weeks old. NC in the different panels, not challenged. Statistical significance was considered as follows: significant at p < 0.05 (*) and highly significant at p < 0.01 (**).Back to article page