Table 12.

Effects of subclinical necrotic enteritis challenge, diet type and supplemental enzymes on caecal volatile fatty acids (μmol/g) at 21 d of age.^1,2

Challenge	Diet type	Enzyme	Formic	Acetic	Propionic	Butyric	Isobutyric	Valeric	Isovaleric	Total VFA3	Succinic	Lactic
Two-way interactions
No	Wheat		0.30b	83.6b	5.3	20.3	0.8c	0.8	0.8	111.4	13.0	1.8
	Maize		0.33b	68.9c	6.2	11.8	1.2b	0.9	1.2	89.7	5.8	0.8
Yes	Wheat		0.76a	96.1a	5.3	18.5	0.9c	0.8	0.9	122.7	9.8	1.8
	Maize		0.53b	69.7c	6.0	11.3	1.4a	1.0	1.4	90.5	3.1	0.8
	Wheat	Control	0.60	88.9	5.1	18.5	0.9	0.8	0.3	115.1	8.0ab	2.2
		XYN10	0.50	90.1	5.1	17.0	0.9	0.7	0.3	114.8	12.5a	1.7
		XYN11	0.49	91.0	5.5	19.9	0.8	0.9	0.3	118.9	11.2a	2.0
		MAN	0.53	89.5	5.3	22.2	0.8	0.9	0.2	119.4	14.0a	1.1
	Mazie	Control	0.37	73.2	6.2	13.9	1.3	1.0	0.5	96.4	7.0ab	0.8
		XYN10	0.44	72.1	5.9	11.4	1.4	1.0	0.5	92.7	3.8b	0.9
		XYN11	0.40	65.1	6.0	11.0	1.2	0.9	0.4	85.1	3.6b	0.6
		MAN	0.49	66.7	6.4	9.8	1.4	1.0	0.5	86.2	3.5b	0.9
Main effects
Challenge		No	0.31	76.2	5.8	16.1	1.0	0.9	0.3b	100.6	9.4a	1.3
		Yes	0.64	82.9	5.6	14.9	1.2	0.9	0.4a	106.6	6.5b	1.3
Diet type		Wheat	0.53	89.9	5.3b	19.4a	0.8	0.8b	0.3b	117.1a	11.4	1.8a
		Maize	0.43	69.3	6.1a	11.5b	1.3	1.0a	0.5a	90.1b	4.5	0.8b
Enzyme		Control	0.49	81.1	5.6	16.2	1.1	0.9	0.4	105.8	7.5	1.5
		XYN10	0.47	81.1	5.5	14.2	1.2	0.9	0.4	103.8	8.2	1.3
		XYN11	0.45	78.1	5.8	15.5	1.0	0.9	0.4	102.0	7.4	1.3
		MAN	0.51	78.1	5.9	16.0	1.1	0.9	0.4	102.8	8.7	1.0
SEM4			0.035	1.61	0.13	0.75	0.03	0.02	0.02	2.16	0.68	0.22
P-value
Challenge			<0.001	0.005	0.676	0.376	<0.001	0.373	<0.001	0.076	0.009	0.988
Diet type			0.087	<0.001	0.001	<0.001	<0.001	<0.001	<0.001	<0.001	<0.001	0.033
Enzyme			0.904	0.645	0.818	0.705	0.063	0.803	0.194	0.868	0.814	0.897
Challenge × diet type			0.042	0.014	0.767	0.620	0.037	0.396	0.190	0.119	0.833	0.955
Challenge × enzyme			0.336	0.471	0.462	0.757	0.353	0.407	0.529	0.501	0.475	0.933
Diet type × enzyme			0.725	0.410	0.865	0.149	0.281	0.446	0.117	0.269	0.019	0.771
Challenge × diet type × enzyme			0.659	0.819	0.341	0.981	0.880	0.157	0.832	0.858	0.316	0.965

^a-c Within a column, means with no common superscripts differ significantly (P < 0.05).

¹Means are based on 6 replicates per treatment with 3 birds per replicate.

²Control = no enzyme; XYN10 = xylanase from family 10; XYN11 = xylanase from family 11; MAN = β-mannanase.

³Total VFA = acetic acid + propionic acid + butyric acid + valeric acid + branched SCFA.

⁴SEM = standard error of the mean.