Table 5.

Means of villus height (VH, µm), crypt depth (CD, µm), and their ratio (V:C) in the duodenum, jejunum, and ileum, crude protein (CP, %), dry matter (DM, %), and ileal digestible energy (IDE, kcal/kg) digestibility, and expression of interferon-γ (INF-γ), interleukin-1β (IL-1β), interleukin-10 (Il-10), and tumor necrosis factor-α (TNF-α) from unchallenged control (0% DTB) and broilers fed 0, 0.125, 0.25, or 0.5% DTB challenged with Eimeria spp. at 20 d of age.

		Treatment					P value	Contrasts		SE
Variables		Unchallenged control	Challenged control	0.125% DTB	0.25% DTB	0.5% DTB		L1	Q
Histomorphology
Duodenum	VH	2465.728a	1527.026b	1559.152b	1610.108b	1536.510b	<0.001	0.924	0.354	67.0283
	CD	160.483c	260.635a	234.129ab	223.841b	231.482ab	<0.001	0.215	0.170	13.9715
	V:C	15.744a	6.065b	6.976b	7.414b	7.006b	<0.001	0.294	0.171	0.6842
Jejunum	VH	1382.489a	858.328b	940.929b	998.384b	902.630b	<0.001	0.717	0.123	67.1898
	CD	144.800	162.473	153.324	172.161	144.701	0.245	0.339	0.300	11.1056
	V:C	9.945a	5.401b	6.338b	5.983b	6.320b	<0.001	0.298	0.498	0.5701
Ileum	VH	788.78	714.538	716.428	752.263	750.636	0.412	0.353	0.747	30.4596
	CD	134.489	138.195	157.568	143.328	138.408	0.515	0.686	0.377	9.9483
	V:C	6.032	5.669	4.610	5.578	5.763	0.263	0.499	0.375	0.4649
Nutrient digestibility
	CP	79.130a	46.508c	57.033b	52.490bc	47.809c	<0.001	0.762	0.097	3.4219
	DM	73.639a	54.382b	54.520b	52.436b	49.333b	<0.001	0.177	0.776	2.7292
	IDE	2998.034a	2139.777b	2131.854b	2117.801b	1894.851b	<0.001	0.129	0.489	110.880
Inflammation markers
	INF-γ	1.000b	1.983a	1.962a	2.614a	1.981a	0.070	0.890	0.337	0.3773
	IL-1β	1.000c	1.291bc	1.902a	1.377bc	1.671ab	0.035	0.523	0.654	0.2059
	IL-10	1.000b	1.644a	1.915a	1.903a	1.874a	0.038	0.612	0.522	0.2325
	TNF-α	1.000	0.985	1.007	1.007	1.142	0.830	0.264	0.685	0.1061

^a,b,cMeans followed by superscript letters are different by Tukey's test (P < 0.05; P < 0.10) within the row.

¹L, linear effect; Q, quadratic effect.

SE = pooled standard error.