. 2022 Nov 17;13:983954. doi: 10.3389/fphys.2022.983954

TABLE 5.

Effects of supplemental Zn source and zinc level on the concentration and mRNA abundance of metallothionine in the pancreas of broilers.

Item	Added Zn mg/kg	Day 7		Day 14
Item	Added Zn mg/kg	MT (ng/g protein)	MT mRNA (fold-change)	MT (ng/g protein)	MT mRNA (fold-change)
Control ^a	0	3.35 ^b	1.01 ^b	1.99 ^b	1.04 ^b
ZnSO₄ ^a	40	3.93	1.30	2.07	2.09
	80	4.61	1.41	2.44	3.06
	120	7.58	1.95	2.43	3.69
Zn-Met ^a	40	4.59	1.32	2.19	2.99
	80	8.74	1.53	2.46	4.01
	120	9.51	2.20	3.33	6.38
Zn-Gly ^a	40	4.29	1.35	2.14	1.95
	80	6.19	1.42	2.35	2.75
	120	9.24	1.95	2.85	3.59
SEM		0.78	0.20	0.21	0.37
Zn-source ^c	ZnSO₄	5.37 ^b	1.55	2.31	2.95 ^b
	Zn-Met	7.61 ^a	1.68	2.66	4.46 ^a
	Zn-Gly	6.58 ^ab	1.57	2.45	2.76 ^b
SEM		0.45	0.11	0.13	0.20
Added Zn ^c	40	4.27 ^c	1.32 ^b	2.13 ^b	2.34 ^c
(mg/kg)	80	6.51 ^b	1.45 ^b	2.41 ^b	3.27 ^b
(mg/kg)	120	8.78 ^a	2.03 ^a	2.87 ^a	4.55 ^a
SEM		0.49	0.10	0.12	0.24
p-value
Zn-source		0.009	0.668	0.217	<0.001
Added Zn		<0.001	<0.001	0.001	<0.001
Interaction		0.289	0.968	0.472	0.077
Linear ^d		<0.001	<0.001	<0.001	<0.001

MT, metallothionein; ZnSO₄, zinc sulfate heptahydrate; Zn-Met, zinc-methionine chelate; and Zn-Gly, zinc-glycine chelate.

^{^a}

Data are mean values of eight replicate pens per treatment.

^{^b}

Different from all Zn supplemental groups (p < 0.05).

^{^c}

Data are mean values of 24 replicate pens per treatment.

^{^d}

Linear effect of the added Zn level.

^a-c Means without the same superscript letters in the same column differ (p < 0.05).