Table 7.

Digestive system development measurements in calves fed starters containing 5% straw differing in particle size either in the pellet (PS) or mixed with the pellet: short (SS), medium (MS), and long straw (LS)

Item	Diet				SEM1	P-value
						Diet	Trial	Diet × trial	Diet
	PS	SS	MS	LS					Linear	Quadratic
Xylose, mg/dL	33.8	30.5	30.5	35.0	1.4	0.02	<0.01	0.73	0.51	<0.01
Slaughter data
Carcass, kg	47.9	47.2	46.4	49.4	1.6	0.57	0.08	0.44	0.59	0.25
Reticulorumen, g	721	766	688	742	45	0.65	<0.01	0.88	0.93	0.92
Omasum, g	245	217	206	200	17	0.27	<0.01	0.97	0.06	0.52
Abomasum, g	265	292	264	265	11	0.25	<0.01	0.98	0.58	0.24
Liver, g	1,135	1,146	1,083	1,107	43	0.73	<0.01	0.95	0.44	0.88
Spleen, g	167	177	159	170	10	0.63	0.01	0.70	0.83	0.99
Organ proportion of BW at harvest
Reticulorumen, %	1.10	1.17	1.06	1.09	0.05	0.55	<0.01	0.74	0.54	0.65
Omasum, %	0.38	0.33	0.32	0.29	0.02	0.06	<0.01	0.62	0.01	0.67
Abomasum, %	0.41	0.45	0.42	0.39	0.02	0.20	0.03	0.69	0.40	0.06
Liver, %	1.76	1.75	1.71	1.64	0.05	0.29	<0.01	0.39	0.08	0.47
Spleen, %	0.26	0.27	0.25	0.25	0.01	0.50	0.19	0.35	0.46	0.69
Papillae length, mm	0.84	0.79	0.77	0.80	0.06	0.85	0.04	0.84	0.54	0.52
Papillae width, mm	0.49	0.49	0.48	0.46	0.02	0.57	<0.01	0.59	0.22	0.54
RWT,2 mm	0.79	0.79	0.80	0.76	0.07	0.97	<0.01	0.90	0.80	0.74

¹Because of unequal animal numbers, SEM differ between treatments; the highest SEM are reported in the table.

²RWT = rumen wall thickness.