Table 4.

Mineral composition and breaking strength of broiler tibia influenced by different dietary levels of Ca and P

Ca (%)	nPP (%)	Ca/nP,P	Tibia ash* (%)	Tibia P*(%)	Tibia Ca*(%)	Tibia breaking strength (N)
0.60	0.27	2.22	46.69b	8.22b	16.14b	79.08b
0.60	0.50	1.20	49.47c	8.88c	16.96b	89.21b
1.10	0.27	4.07	37.22a	6.12a	13.08a	54.86a
1.10	0.50	2.20	51.31d	9.12c	18.20c	115.27c
SEM			0.253	0.06	0.222	2.648
Main effects
Ca levels
0.60			48.08	8.55	16.55	84.14
1.10			44.26	7.62	15.64	85.07
nPP levels
0.27			41.96	7.17	14.61	66.97
0.50			50.39	9.00	17.58	102.24
Source of variation			———p-value———
Ca levels			<0.001	<0.001	0.059	0.864
nPP levels			<0.001	<0.001	<0.001	<0.001
Ca levels×nPP levels			<0.001	<0.001	<0.001	<0.001

^a–dWithin comparisons, means in a column with no common superscripts differ significantly (p≤0.05). n = 6.

^*Results were expressed on dry-defatted weight basis of tibia.