Table 1.

Ingredient and chemical composition of the basal diets

Item	High forage1		High grain1
	Control	Monensin	Control	Monensin
Ingredients, % of DM
Barley silage	65.0	65.0	8.0	8.0
Barley, dry rolled	25.0	25.0	87.0	87.0
Supplement	10.0	10.0	5.0	5.0
Canola meal	3.966	3.967	1.521	1.521
Barley, ground	5.520	5.504	2.170	2.154
Canola oil	0.051	0.051	0.052	0.052
Limestone	0.135	0.135	0.922	0.922
Salt	0.047	0.047	0.048	0.048
Urea	0.180	0.180	0.184	0.184
Molasses	0.056	0.056	0.057	0.057
Feedlot premix2	0.045	0.045	0.046	0.046
Rumensin	—	0.016	—	0.016
Chemical composition3
DM, %	50.7 ± 0.31	50.7 ± 0.31	86.8 ± 1.11	86.8 ± 1.10
OM, %	92.7 ± 0.27	92.7 ± 0.31	96.4 ± 0.47	96.3 ± 0.44
CP, %	14.2 ± 0.52	14.2 ± 0.61	13.9 ± 0.86	13.9 ± 0.88
NDF, %	40.5 ± 1.52	40.4 ± 1.48	18.4 ± 0.63	18.4 ± 0.67
ADF, %	21.5 ± 0.50	21.5 ± 0.49	7.03 ± 0.7f2	7.05 ± 0.74
Starch, %	31.7 ± 1.81	31.8 ± 1.68	54.9 ± 2.86	54.8 ± 2.88

¹The high-forage diet was fed from d 1 to d 105 (backgrounding phase) followed by sequential adaptation (transition phase) to a high-grain diet (finishing phase, 105 d).

²Feedlot vitamin–mineral premix contained CaCO₃, 34.83%; CuSO₄, 10.31%; ZnSO₄, 28.37%; ethylenediamine dihydriodide (80% concentration), 0.15%; selenium 1% (10,000 mg Se/kg), 5.04%; CoCO₃, 0.08%; MnSO₄, 14.61%; vitamin A (500,000,000 IU/kg), 1.72%; vitamin D (500,000,000 IU/kg), 0.17%; and vitamin E (500,000 IU/kg), 4.73%.

³Determined using samples pooled by diet every 3 wk within each phase; all values except DM are expressed on a DM basis.