Optimal dietary copper requirements and relative bioavailability for weanling pigs fed either copper proteinate or tribasic copper chloride

Table 5 Effect of amount and source of dietary copper on plasma, bile, intestinal, and liver copper concentrations of weanling pigs

	Copper source¹	Copper level, mg/kg						Pooled SEM	P-value
	Copper source¹	0	20	40	80	160	200	Pooled SEM	Treatment	Linear	Quadratic
Plasma, μg/mL	TBCC	1.40	1.41	1.41	1.39	1.38	1.36	0.02	0.320	0.029	0.074
Plasma, μg/mL	CuPro	1.40	1.42	1.40	1.39	1.38	–	0.02	0.390	0.144	0.350
Bile, μg/mL	TBCC	0.92^d	0.89^d	1.95^c	2.87^b	3.23^a	3.20^a	0.03	< 0.001	< 0.001	< 0.001
Bile, μg/mL	CuPro	0.92^e	1.10^{d, *}	2.36^{c, *}	3.21^{b, #}	3.44^{a, *}	–	0.04	< 0.001	< 0.001	< 0.001
Liver, mg/kg	TBCC	23.43^b	23.58^b	24.12^b	24.00^b	32.96^a	33.92^a	0.61	< 0.001	< 0.001	< 0.001
Liver, mg/kg	CuPro	23.43^c	23.58^c	23.77^c	31.91^{b, *}	37.01^{a, *}	–	0.41	< 0.001	< 0.001	< 0.001
Duodenum, mg/kg	TBCC	2.80^bc	2.77^c	2.80^bc	2.89^b	3.41^a	3.38^a	0.02	< 0.001	< 0.001	< 0.001
Duodenum, mg/kg	CuPro	2.80^c	2.80^c	2.83^c	3.06^{b, *}	3.58^{a, *}	–	0.02	< 0.001	< 0.001	< 0.001
Jejunum, mg/kg	TBCC	5.01^c	4.97^c	5.05^bc	5.07^bc	5.15^b	5.28^a	0.03	< 0.001	< 0.001	< 0.001
Jejunum, mg/kg	CuPro	5.01^c	5.09^{bc, *}	5.10^bc	5.12^{b, *}	5.30^{a, *}	–	0.02	< 0.001	< 0.001	< 0.001

^a-d Means within a row without a common superscript letter are different (P < 0.05)
* different from the corresponding TBCC group at the same supplemented copper level, P < 0.05
^# tend to be different from the corresponding TBCC group at the same supplemented copper level, 0.05 < P < 0.10
¹TBCC tribasic copper chloride, CuPro copper proteinate

ISSN: 2049-1891