Hens from the Blue-shell breed could be categorized into 3 groups according to the number of nesting and broody days (i.e., nonbroody, atypical broody, and typical broody; Table 3). Nonbroody hens used nests only for egg laying. Nontypical broody hens exhibited no obvious broody behavior but did exhibit sporadic nesting behav- ior. Typical broody was defined as hens with consecutive nesting behavior and characteristic activities associated with broodiness. During the experimental period, more than 30% of the hens showed typical broodiness, and of these about a third became broody more than once. The mean duration of broody cycle was 28.8 ± 2.6 d.