Table 3.

The physical, mechanical, and geometric properties of tibia obtained from 42-day-old broilers in the control group and supplemented with Cu in 25% of daily demand dependently on phytase supplementation

Item	Group			SEM	P value
	0 Suppl (n = 10)	Cu25% (n = 10)	Cu25% + phyt (n = 10)
Bone general properties
Bone weight (g)	19.4a	20.1a	26.2b	0.9	P < 0.001
Bone length (mm)	110a	110a	115b	1	P < 0.001
Bone weight/bone length (g mm−1)	0.176a	0.182a	0.228b	0.01	P < 0.001
Bone geometrical properties
Horizontal internal diameter h (mm)	4.41a	5.08b	5.76c	0.20	P < 0.001
Horizontal external diameter H (mm)	6.83a	8.62b	11.18c	0.50	P < 0.001
Vertical internal diameter b (mm)	2.07a	4.46b	4.81b	0.33	P < 0.001
Vertical external diameter B (mm)	4.52a	7.44b	8.70c	0.49	P < 0.001
Cross section area A (mm2)	17.1a	32.6b	55.0c	4.5	P < 0.001
Mean relative wall thickness MRWT (–)	0.86a	0.71b	0.89a	0.04	P = 0.009
Cortical index CI (%)	44.3ab	40.9a	46.3b	1.1	P = 0.024
Midshaft volume (cm3)	0.76a	1.44b	2.53c	0.21	P < 0.001
Moment of inertia Ix (mm4)	30a	157b	348c	40	P < 0.001
Index of gyration Rg (mm)	1.31a	2.16b	2.45c	0.14	P < 0.001
Bone mechanical properties
Yield strength (N)	149a	158a	383b	29	P < 0.001
Ultimate strength (N)	239a	248a	549b	40	P < 0.001
Elastic stress (MPa)	133a	46b	61b	11	P < 0.001
Ultimate stress (MPa)	215a	69b	86b	18	P < 0.001
Bending moment (N·m)	1.64a	1.75a	4.41b	0.35	P < 0.001

Mean values in rows with different lowercase letters differ significantly at P < 0.05; data given are means

SEM standard error of the mean, 0 Suppl the control group without received Cu in premix, Cu25% the group received Cu in 25% of daily demand from Cu-Gly, Cu25% + phyt the group received Cu in 25% of daily demand from Cu-Gly with phytase