Table 1. Ileal digestibility coefficients of calcium (Ca) for inorganic sources in broiler chickens

Ingredient	Total Ca	Ca:NPP ratio	Digestibility	Method	Reference
Dicalcium phosphate	9.0	1.1	0.32	Direct	[58]
	9.0	1.1	0.28, 0.34	Direct	[15]
	8.6	1.2, 2.0	0.21, 0.25	Difference	[15]
	2.9–8.6	1.1–1.2	0.13	Regression	[15]
	3.3–5.3	0.9–1.0	0.67	Regression	[59]
Monocalcium phosphate	9.0	0.6–0.7	0.43	Direct	[58]
	9.0	0.8	0.33	Direct	[15]
Limestone	9.0	1.1	0.51	Direct	[58]
	9.0	2.0	0.27–0.53	Direct	[44]
	8.0	2.0	0.46	Direct	[60]
	9.0	2.0	0.57–0.62	Direct	[61]
	9.0	2.0	0.50	Direct	[62]
	3.3–5.3	0.9, 1.0	0.64	Regression	[59]