Table 3. Number of fractures observed in the caudal part of the keel bone by histological evaluation.

Age	No. of birds	No. of fractures
		0	1	2	3	4	5	6
>75 weeks	49 (14a/35b)	18 (10/8)	20 (4/16)	5 (0/5)	3 (0/3)	2 (0/2)	0 (0/0)	1 (0/1)
32 weeks	13 b	6	6	1	0	0	0	0

^a Caged birds.

^b Cage-free birds.