Table 3.

Effect of Bacillus subtilis PB6 and/or chromium propionate supplementation on growth performance, DMI, and feed efficiency of beef steers during the feedlot receiving period

	Treatmenta					P-value
Item	CON	CST	CHR	CST + CHR	SEMb	CST	CHR	CST × CHR
BW, kg
Initialc	219	220	220	220	0.39	0.13	0.86	0.04
Day 14	230	234	230	233	1.43	0.04	0.99	0.73
Day 28	246	250	247	249	1.79	0.06	0.87	0.48
Day 56	287	298	291	293	2.67	0.02	0.95	0.16
ADG, kg
Initial to day 14	0.78	0.95	0.77	1.01	0.10	0.04	0.85	0.69
Days 14–28	1.12	1.20	1.16	1.12	0.11	0.84	0.86	0.62
Days 28–56	1.47	1.68	1.57	1.59	0.06	0.06	0.95	0.12
Initial to day 56	1.21	1.37	1.27	1.31	0.05	0.04	0.95	0.26
DMI, kg/d
Days 0–14	3.50	3.75	3.52	3.80	0.11	0.02	0.75	0.87
Days 14–28	5.13	5.55	5.13	5.50	0.17	0.02	0.86	0.90
Days 28–56	6.61	7.12	6.80	7.08	0.16	0.03	0.55	0.41
Days 0–56	5.46	5.88	5.58	5.86	0.13	0.01	0.70	0.60
G:F, kg
Days 0–14	0.2241	0.2551	0.2183	0.2681	0.0230	0.08	0.89	0.70
Days 14–28	0.2082	0.2098	0.2209	0.1833	0.0192	0.35	0.72	0.32
Days 28–56	0.2253	0.2367	0.2291	0.2250	0.0066	0.56	0.58	0.23
Days 0–56	0.2223	0.2337	0.2274	0.2245	0.0058	0.45	0.74	0.22

^aCON = placebo control; CST = 13 g per animal daily DM inclusion of Bacillus subtilis PB6 (CLOSTAT, Kemin Industries, Des Moines, IA); CHR = 450 ppb DM chromium propionate (KemTRACE Chromium, Kemin Industries); CST + CHR = 13 g per animal daily DM inclusion of Bacillus subtilis PB6 + 450 ppb DM chromium propionate.

^bStandard error of least square mean.

^cInitial = average of day −1 and day 0 BW.