The effect of β-mannanase and β-glucanase on small intestine morphology in male broilers fed diets containing various levels of metabolizable energy

Figures & data

Table 1. Ingredients and composition of the basal diets (g/kg) with low and normal ME levels.

	Starter diets (1–12 days)		Grower diets (13–21 days)
Ingredients	Low ME	Normal ME	Low ME	Normal ME
Ground barley	400	400	400	400
Soybean meal (44% CP)	425	425	383.3	383.3
Ground yellow corn (44% CP)	22.2	22.2	46.8	46.8
Soya oil	93.9	105.7	114.7	126.5
Dicalcium phosphate	17.5	17.5	15.3	15.3
Oyster shell	14.8	14.8	13.7	13.7
Sodium chloride	3.5	3.5	3.5	3.5
Vitamin premix^a	3	3	3	3
Mineral premix^b	3	3	3	3
DL-methionine	2.1	2.1	2.2	2.2
Lysine HCl	1.2	1.2	0.8	0.8
Indigestible substance	11.8	0	11.8	0
Hemicell^c	±	±	±	±
Rovabio^d	±	±	±	±
Total	1000	1000	1000	1000
Calculated analysis
AME (Kcal/kg)	2900	3000	3075	3175
Crude protein (%)	23.36	23.36	21.72	21.72
Calcium (%)	1	1	0.9	0.9
Available phosphorus (%)	0.5	0.5	0.45	0.45

± , 0 or 1 g/kg (0 g/kg substituted with 1 g/kg indigestible substance).

^a Vitamin premix supplied the following (per kilogram of basal diet): vitamin A, 12,600 IU; vitamin D3, 2200 ICU; vitamin E, 10 IU; vitamin K, 3.5 mg; riboflavin 6.6 mg; niacin, 40.0 mg; pantothenic acid, 14.4 mg; vitamin B12, 0.012 mg; folic acid, 1.0 mg; pyridoxine, 1.2 mg.

^b Mineral premix supplied the following (per kilogram of basal diet): Mn, 55 mg; Cu, 10 mg; Zn, 50 mg; Fe, 30 mg.

^c As a source of β-D-mannanase.

^d As a source of β-D-glucanase.

Figure 1. Representative light micrographs of intestinal villus morphometry in the experimental chicks. (A) Villi length (L), width (w) and crypt depth (d) in tall villus. (B) Villi length (L) and width (w) in a tongue-shaped villi. (C) Villi length (L), width (w) and crypt depth (d) in short villus. (D) Crypt depth (d) at 10×. (E) Crypt depth (d) at 4×.

Table 2. Effects of ME and enzymes levels and all their interactions on duodenal morphology of 21-day-old male broiler intestines (LSM ± SEM).

Item	Villus length (µm)	Villus width (µm)	crypts depth (µm)
ME levels
L	1178.38 ± 40.52	281.5 ± 8.84	152.17 ± 5.28
N	1248.67 ± 42.5	265.13 ± 9.68	145.63 ± 5.79
G enzyme levels
0	1112.21 ± 42.5^b	279.13 ± 9.27	151.75 ± 5.79
1 (g/kg)	1314.83 ± 4052^a	267.5 ± 9.27	146.04 ± 5.28
M enzyme levels
0	1139.54 ± 42.5^b	212.25 ± 9.68^b	137.83 ± 5.54^b
1 (g/kg)	1287.5 ± 40.52^a	334.38 ± 8.83^a	159.96 ± 5.54^a
Effect (p value)
Energy levels	0.2565	0.2399	0.4233
G enzyme levels	0.0054	0.3958	0.4830
M enzyme levels	0.0258	<0.0001	0.0180
ME × G	0.7238	0.0196	0.6172
ME × M	0.0703	0.0008	0.3102
ME × G × M	0.0023	0.0942	0.0084

Note: Values with different superscript letters indicate significant differences with P < 0.05.

ME, metabolizable energy; G enzyme, β-glucanase enzyme; M enzyme, β-mannanase enzyme; ME × G, ME vs. β-glucanase interaction; ME × M, ME vs. β-mannanase interaction; ME × M × G, ME vs. β-mannanase vs. β-glucanase interaction.

Table 3. Effects of ME and enzymes levels and all their interactions on jejunal morphology of 21-day-old male broiler intestines (LSM ± SEM).

Item	Villus length (µm)	Villus width (µm)	crypts depth (µm)
ME levels
L	642.21 ± 36.73	279.75 ± 11.38	126.75 ± 3.33^a
N	596.79 ± 36.73	278.54 ± 10.29	112.38 ± 3.01^b
G enzyme levels
0	566.5 ± 38.36	291.21 ± 10.85	124.04 ± 3.01
1 (g/kg)	672.5 ± 35.02	267.08 ± 10.85	115.08 ± 3.33
M enzyme levels
0	585.67 ± 36.73	286.67 ± 10.29	125.83 ± 3.01^a
1 (g/kg)	653.33 ± 36.73	271.63 ± 11.38	113.29 ± 3.33^b
Effect (p value)
Energy levels	0.4024	0.9385	0.0076
G enzyme levels	0.0686	0.1418	0.0694
M enzyme levels	0.2219	0.3462	0.0163
ME × G	0.0011	0.3593	0.0207
ME × M	0.3796	0.6812	0.1430
ME × G × M	0.9156	0.1262	<0.0001

Note: Values with different superscript letters indicate significant differences with P < 0.05.

ME, metabolizable energy; G enzyme, β-glucanase enzyme; M enzyme, β-mannanase enzyme; ME × G, ME vs. β-glucanase interaction; ME × M, ME vs. β-mannanase interaction; ME × M × G, ME vs. β-mannanase vs. β-glucanase interaction.

Table 4. Effects of ME and enzymes levels and all their interactions on ileal morphology of 21-day-old male broiler intestines (LSM ± SEM).

Item	Villus length (µm)	Villus width (µm)	crypts depth (µm)
ME levels
L	375.33 ± 11.22	283.08 ± 8.65	126.75 ± 3.33^a
N	356.96 ± 10.15	257.29 ± 8.25	112.38 ± 3.01^b
G enzyme levels
0	337.67 ± 10.69^b	272.17 ± 8.65	124.04 ± 3.01
1 (g/kg)	394.63 ± 10.69^a	268.21 ± 8.25	115.08 ± 3.33
M enzyme levels
0	336.13 ± 10.69^b	268.38 ± 7.83	125.83 ± 3.01^a
1 (g/kg)	396.17 ± 10.69^a	272 ± 9.04	113.29 ± 3.33^b
Effect (p value)
ME levels	0.2479	0.0539	0.0076
G enzyme levels	0.0027	0.7468	0.0694
M enzyme levels	0.0019	0.7673	0.0163
ME × G	0.0082	0.3135	0.0207
ME × M	0.7407	0.0278	0.1430
ME × G × M	0.2661	0.0012	<0.0001

Note: Values with different superscript letters indicate significant differences with P < 0.05.

ME, metabolizable energy; G enzyme, β-glucanase enzyme; M enzyme, β-mannanase enzyme; ME × G, ME vs. β-glucanase interaction; ME × M, ME vs. β-mannanase interaction; ME × M × G, ME vs. β-mannanase vs. β-glucanase interaction.