. 2018 Feb 28;96(3):1159–1170. doi: 10.1093/jas/skx063

Table 7.

Main effect of trace mineral supplementation* on liver mineral status of nonimplanted or implanted† beef steers

Mineral, mg/kg DM‡	CON, n = 12	REC, n = 12	IND, n = 11	SEM	P value; TM
Initial (day −7)
Cu	224	221	233	—	—
Zn	106	104	112	—	—
Mn	9.42	9.25	9.52	—	—
Se	1.8	1.7	1.6	—	—
Co	0.232	0.241	0.249	—	—
Day 70∥
Cu	118^c	233^b	290^a	10.0	<0.01
Zn	97	98	95	3.9	0.89
Mn	7.63^b	8.25^a,b	8.90^a	0.276	0.01
Se	2.1^b	2.3^a,b	2.7^a	0.11	<0.01
Co	0.147^b	0.192^a	0.189^a	0.0117	0.02
Harvest (day 125)∥
Cu	137^b	277^a,b	310^a	19.0	<0.01
Zn	126^b	144^a	133^a,b	4.9	0.04
Mn	7.61^b	9.10^a	9.75^a	0.359	<0.01
Se	2.0^c	2.5^b	2.9^a	0.112	<0.01
Co	0.135^b	0.184^a	0.179^a	0.0081	<0.01

^a,b,cWithin rows, means without a common superscript differ (P ≤ 0.05).

^*Supplemental trace mineral treatments: CON (no additional supplemental trace minerals), REC (2016 NASEM recommendations: 10 Cu, 30 Zn, 20 Mn, 0.10 Se, 0.15 Co, and 0.50 I; mg/kg), and IND (feedlot consultant recommendations from Samuelson et al. (2016) of 20 Cu, 100 Zn, 50 Mn, 0.30 Se, 0.20 Co, and 0.50 I; mg/kg). Sources of trace mineral included copper sulfate, zinc sulfate, manganese sulfate, calcium iodate, sodium selenite, and cobalt carbonate.

^†Growth-stimulated implanted steers (IMP) received Component TE-IS (16 mg estradiol + 80 mg TBA) on day 0 and were reimplanted with Component TE-200 (20 mg estradiol + 200 mg TBA) on day 56, whereas NoIMP received no implants.

^‡No GS × TM; P ≥ 0.11.

^∥Day −7 mineral concentrations were used as a covariate in analysis.

SEM, standard error of the mean.