FIG. 5.

Clinical signs scoring of day-old or 2-week-old turkeys inoculated with avirulent goose 15a/01 and challenged with virulent turkey 2a/97 virus 2 weeks later. The clinical signs were scored for each bird as described in Materials and Methods (on a scale of 0 to 4) averaged per time point after challenge and also presented as the percentage of birds showing disease at each time point after challenge. (A) Average clinical sign score and (B) percent showing clinical signs for birds vaccinated at 1 day old. (C) Average clinical score and (D) percent showing clinical signs for birds vaccinated at 2 weeks old.