Effect of Dietary Inclusion of Soybean Hulls in Basal Diet on Digesta Viscosity, Fecal Consistency, Hematology, Serum Biochemistry, and Intestinal Morphometric Parameters in the Laying Hens During Peak Egg Production Stages
Effect of Dietary Inclusion of Soybean Hulls in Basal Diet on Digesta Viscosity, Fecal Consistency, Hematology, Serum Biochemistry, and Intestinal Morphometric Parameters in the Laying Hens During Peak Egg Production Stages
Muhammad Shuaib1*, Abdul Hafeez1, Woo Kyun Kim2, Aamir Khan3 and Abubakar Sufyan4
1Department of Poultry Science, Faculty of Animal Husbandry and Veterinary Sciences, The University of Agriculture Peshawar, Pakistan
2Department of Poultry Science, University of Georgia, Athens, GA 30602
3Directorate General (Research), Livestock and Dairy Development Department, Khyber Pakhtunkhwa Peshawar
4Department of Livestock and Poultry Production, Bahauddin Zakariya University, Multan, Pakistan
ABSTRACT
This study aimed to investigate the effect of soybean hull (HS) in the diet of laying hens on digesta viscosity, fecal consistency, hematology, serum biochemistry, and intestinal morphometrics during peak egg production periods. A total of 160, 28-weeks old golden misri (brown) laying hens were distributed in the following groups. A basal diet of the corn-soybean meal was formulated as a control group and a soybean meal in the basal diet was replaced with 3%SH, 6%SH, and 9% SH respectively. The results of the feces proximate analysis showed significantly higher crude protein during phases 1 and 2, while crude fiber during phase1 and 3 for the SH treatment groups. The crude fat had a significantly higher value for the control group than all SH treatment groups during all (three) phases. The ash amount was significantly higher in the 3 and 6% SH groups during phase 1 while 6% and 9% SH groups during phase 3 than in all other groups. The control group had (P<0.05) lower gut contents viscosity during all phases than the SH treatment groups. During all phases, the feces consistency was normal (dry and cone farming) for the control and 3% SH groups while loose droppings but no free water for the 6% and 9%SH treatment groups. The hematological and serum biochemistry parameters were not affected during all phases. The control group had significantly higher duodenum villus height and crypt depth during all phases while ileum villus height was significantly lower in the 9%SH treatment group than in all other groups. In conclusion, the dietary supplementations of soybean hulls increased the digesta viscosity, and have no adverse effect on fecal consistency, hematological and serum biochemistry, and intestinal morphometric parameters in the laying hens during the peak egg production period.
Article Information
Received 24 April 2022
Revised 18 June 2022
Accepted 01 July 2022
Available online 13 October 2022
(early access)
Published 27 March 2024
Authors’ Contribution
MS animal trial, laboratory experiment, statistical analysis, study design, and writing. AH study design, feed formulation, data evaluation, manuscript review. WKK data evaluation, manuscript review. AK data analysis, manuscript review. AS data analysis, manuscript review.
Key words
Soybean hull, Proximate analysis, Viscosity, Hematology, Histomorphology
DOI: https://dx.doi.org/10.17582/journal.pjz/20220424140433
* Corresponding author: [email protected]
0030-9923/2024/0003-1079 $ 9.00/0
Copyright 2024 by the authors. Licensee Zoological Society of Pakistan.
This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
INTRODUCTION
Soybean hull is the byproduct of Soybean seed after the extraction of oil and a very valuable feed ingredient available on farm feeding for cattle and other species including poultry birds. Soybean hulls contain different quantities of celluloses (29-51 %), hemicelluloses (10-25 %), proteins (11-15 %), lignin (1-4 %), and pectins (4-8 %) (Mielenz et al., 2009) which is associated with the de-hulling process (Rojas et al., 2014). These outer coverings are very valuable for ruminant animals due to their fibrous nature and hence, fail to find any room in human food (Ipharraguerre and Clark, 2003). Especially in regards to the welfare of laying and breeding hens and feed restriction programmers, the use of soybean hulls is quite common these days (Esonu et al., 2005). Soybean hulls are abundantly available in the market at very low costs and the successful feed manufacturing business of the country has moved to bring in whole grain in place of soybean meal from Brazil and the USA (Khurshid et al., 2017). Soybean hull contains both soluble and insoluble fiber components and the soluble fiber (i.e., pectins, gums, and mucilages) can hold water and increase the viscosity of the digesta and change the nutrient absorption (Langhout et al., 2000; Owusu-Asiedu et al., 2006; Tellez et al., 2014; Perera et al., 2019). The non-starch polysaccharides (NSPs) are not only poorly digested by birds but also negatively affect bird physiology, and those adverse effects include altered intestinal transit time, change in intestinal mucosal structure, and hormonal deregulation (Vahouny, 1982). Hens are also known more tolerant to the high-fiber diet compared to fast-growing broilers (Walugembe et al., 2014) The interest in the effect of high-fiber content in diets on the digestive physiology of animals has increased, especially among monogastric animals, in which the knowledge of microorganisms involved in fiber breakage is still limited when compared with polygastric species (Castro Júnior et al., 2005). Due to high fiber concentration, soybean hulls are not commonly a part of poultry regimes; however, positive inclusion of soybean hulls has been reported in poultry rations (Muir et al., 1985; Newkirk, 2010). Therefore, the present study aimed to determine the effect of the inclusion of soybean hulls in different concentrations in the basal diet on digesta viscosity, fecal consistency, hematology, serum biochemistry, and intestinal morphometric parameters in laying hens during peak egg production stages.
MATERIALS AND METHODS
Availability of experimental diets
The experiment was approved by the ethical committee of the Faculty of Animal Husbandry and Veterinary Science, The University of Agriculture Peshawar, Pakistan. Four types of experimental feed were prepared on Sadiq brother Company (Rawalpindi). A control group containing a basal diet (corn-soybean meal) and 3%, 6%, and 9% SH treatment diets were formulated by replacing soybean meal in the basal diet with 3, 6, and 9% soybean hulls (SH). The chemical composition of the experimental diets is presented in Table I.
Housing and experimental birds
A total of 160, 28 weeks old golden misri (brown) layer birds were distributed in a complete randomized design with 4 dietary treatments and 4 replicates of 10 birds each. All the birds were reared together in cages from 29 weeks to 40 weeks of age. The experimental diets were fed to birds in three phases: (phase-1=week 29 to 32, phase-2=week 33 to 36, and phase-3=week 37 to 40). Each cage (120cm long×72cm wide×46cm height) was equipped with one drinker and one feeder, providing ad libitum access to water. The room temperature was kept at 75°F and was equipped with sufficient light (17h /day). Routine vaccination schedules and uniform environmental and management conditions were provided to all the birds in the experimental house.
Table I. Experimental diet composition.
Nutrient % |
Control |
3% SH1 |
6% SH |
9% SH |
Corn |
53.12 |
53.18 |
50.90 |
48.46 |
Canola meal |
4.00 |
4.00 |
4.00 |
5.00 |
Soybean meal |
24.34 |
23.28 |
22.56 |
21.84 |
Guar meal |
1.00 |
0.00 |
0.00 |
0.00 |
Soybean hull |
0.00 |
3.00 |
6.00 |
9.00 |
PBM Hi fat |
2.00 |
1.02 |
1.02 |
00 |
Poultry oil/fat |
2.79 |
2.79 |
2.79 |
2.97 |
Salt sodium |
0.32 |
0.32 |
0.32 |
0.32 |
Bicarbonate/soda |
0.10 |
0.10 |
0.10 |
0.10 |
Limestone/chips |
11.19 |
11.19 |
11.19 |
11.19 |
DCP |
0.77 |
0.77 |
0.77 |
0.77 |
DLM |
0.08 |
0.08 |
0.08 |
0.08 |
Choline chloride (70%) |
0.10 |
0.10 |
0.10 |
0.10 |
Vitamin premix2 |
0.07 |
0.07 |
0.07 |
0.07 |
Mineral premix |
0.06 |
0.06 |
0.06 |
0.06 |
Phytase |
0.01 |
0.01 |
0.01 |
0.01 |
Enramycin |
0.02 |
0.02 |
0.02 |
0.02 |
Ethoxyquin/antioxidant |
0.01 |
0.01 |
0.01 |
0.01 |
NSPs |
0.02 |
0.00 |
0.00 |
0.00 |
1SH= abbreviated for soybean hull. 2To provide one kg of diet: Retinyl acetate, 4400 IU; DL-α-tocopheryl acetate, 12 IU; Cholecalciferol, 118µg; Thiamine, 2.5mg; Menadione sodium bisulphite, 2.40 mg; Niacin, 30mg; vit.B2, 4.8 mg; D-Pantothenic acid, 10 mg; vit. B6, 5 mg; vit. B7, 130 µg; Cyanocobalamine, 19 µg; vit.B9, 2.5 mg; Mn, 85 mg; Zinc, 75 mg; Fe, 80 mg; Iodine, 1 mg; Selenium, 130 µg; Copper, 6 mg.
Proximate analysis of feces
Proximate analysis was performed for excreta samples. The samples were properly thawed and mixed to create homogenous representative samples and then air-dried in an oven at 60°C for 3 days. The excreta samples were ground in Thomas-Willey mill up to 1 mm particle size and stored in labeled bottles at room temperature. Excreta samples were subjected to the proximate analysis for crude protein (CP), crude fiber (CF), dry matter (DM), ether extract (EE), and ash according to the procedure explained by (AOAC, 2000).
Gut viscosity and fecal consistency
The viscosity of intestinal contents was measured with a Brookfield digital viscometer (Model: LVDV-E, P40 adaptor). Total intestinal contents were taken from the gizzard to Meckel’s diverticulum (proximal samples) and from Meckel’s diverticulum to the ileo-ceco-colic junction (distal samples). For viscosity analysis, 1.5 g of fresh digesta was instantly put in a microcentrifuge tube and centrifuged for 5 min at 12,700 x g. The supernatant was removed and viscosity was determined using a Brookfield digital viscometer at a shear rate of 42.5 sec-1 at 40°C (Bedford and Classen, 1993). On the last day of each phase, excreta were visually observed and scored: (1) normal dry droppings and coning; (2) loose droppings, some coning, but no free water; (3) loose droppings with slight coning and some free water; (4) extremely loose droppings with no coning and large amounts of free water as described by Roland et al. (1985).
Hematology and serum biochemistry
Blood samples were collected from four birds of each replicate on the last day of each phase and examined for white blood cells (WBCs) count, red blood cells (RBCs) count, the concentration of hemoglobin, and packed cell volume (PCV). Wright and Giemsa stain fixed monolayer blood films were used for the estimation of differential white blood cells. Haemocytometer was used for the manual calculation of total white blood cells and total red blood cells (Campbell, 1995). PCV was measured by a standard manual technique using micro hematocrit capillary tubes and centrifuged at 2,500 rpm for 5 min. Cyanmethemoglobin methodology was implemented for the estimation of hemoglobin (Hb) concentration in blood. Erythrocyte indices mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentrations (MCHC) were calculated from total red blood cells (TRBC), PCV, and Hb. Other blood parameters, for instance, complete picture blood, heterophile to lymphocyte ratio, blood protein, and plasma total cholesterol were examined in the collected blood samples. Zak-Henly and the chemical methods were adopted for the estimation of cholesterol and protein in the blood, respectively (Lowry et al., 1951; Zak, 1957; Henly, 1957). Commercially available diagnostic kits (LAB KIT, (Barcelona) Spain) were used for the determination of serum attributes such as total cholesterol (TC), high-density lipoprotein (HDL), and low-density lipoprotein (LDL). The equation used for the calculation of LDL and Very-Low-Density Lipoprotein (VLDP) in the plasma of collected blood samples is LDL + VLDL = TC - HDL.
Intestinal morphometric parameters
The parameters of intestine morphology were studied according to the procedure explained by Feng et al. (2007). In brief, small pieces from the central portions of the intestinal duodenum, jejunum, and ileum were obtained and placed in 10% formalin after careful flushing and detachment of the part. At least four cross-sections were prepared for every sample of the intestinal part taken, using the embedding technique in the microtome. Width, height, crept depth, and surface area of the intestine villus was evaluated at Veterinary Research Institute (VRI) Peshawar using an imaging microscope (Nikon Eclipse 50, Nikon Corporation Japan), specially designed for the intestinal morphometric measurements.
Table II. Proximate analysis of feces during different phases.
Item % |
Control |
3% SH1 |
6% SH |
9% SH |
SEM |
P value |
Phase 1 |
||||||
Dry matter |
72.77 |
72.50 |
73.51 |
73.61 |
0.52 |
0.689 |
Crude protein |
23.03c |
26.21b |
28.14ab |
29.92a |
0.60 |
0.023 |
Crude fiber |
11.91b |
12.47ab |
13.68a |
13.93a |
0.21 |
0.014 |
Crude fat |
1.80a |
1.69b |
1.66bc |
1.64c |
0.05 |
0.001 |
Ash |
31.55b |
34a |
34.19a |
32.84b |
0.96 |
0.037 |
Phase 2 |
||||||
Dry matter |
71.34 |
71 |
70.40 |
70.17 |
0.43 |
0.306 |
Crude protein |
25.27b |
27.32a |
27.63a |
28.96a |
0.52 |
0.023 |
Crude fiber |
12.85 |
13.66 |
14.02 |
14.66 |
0.45 |
0.201 |
Crude fat |
1.72a |
1.64b |
1.61c |
1.60c |
0.04 |
0.017 |
Ash |
31.51 |
33.43 |
32.74 |
31.66 |
0.67 |
0.056 |
Phase 3 |
||||||
Dry matter |
69.79 |
72.21 |
72.58 |
71.20 |
0.67 |
0.541 |
Crude protein |
24.89 |
25.44 |
26.11 |
26.49 |
0.91 |
0.117 |
Crude fiber |
11.91b |
12.79c |
13.88ac |
15a |
0.62 |
0.021 |
Crude fat |
1.76a |
1.67b |
1.64bc |
1.62c |
0.28 |
0.030 |
Ash |
29.71c |
30.14c |
33.91a |
34.4a |
1.17 |
0.013 |
Means in the same row with different superscripts are significantly different (P<0.05). 1SH, Abbreviated for Soybean hull.
RESULTS
The result for feces proximate analysis during different phases is presented in Table II. Dry matter (DM) during all phases remained non-significant among the treatment groups. During phase-1 and 2, crude protein (CP) had (P<0.05) higher values in the 9% SH group than in the control group, whereas during phase-3 there was no difference in CP (P˃0.05). Crude fiber (CF) was recorded (P<0.05) higher in the 9% SH group during phase-1 and 3 than in the control group, however, there was no difference (P>0.05) during phase-2. Similarly, Fat % was (P<0.05) higher in the control group compared to all other treatment groups during all phases. During phase-1, the 6% SH group had (P<0.05) higher ash amount as compared to the control and 9% SH groups (P<0.05), whereas there was no significant difference in phase-2 but the 9% SH group had higher (P<0.05) ash in phase-3 than that of the control and 3% treatment groups. The effect of soybean hulls on gut viscosity and feces consistency is presented in Table III. During all phases, the gut viscosity of the 9% SH group was (P<0.05) higher as compared to all other groups. Feces consistency during all phases for the control and 3% SH treatment groups were observed normal (dry droppings and coning), while 6% and 9%SH treatments had loose droppings, some coning, but no free water. Results for the effect of soybean hulls on hematological and serum biochemistry parameters are presented in Table IV. During all phases, there were no significant differences (P>0.05) in RBCs, WBCs, PCV, HB, MCHC, MCV, TC, HDL, LDL, VLDL, heterophile, lymphocytes, and heterophile to
Table III. Effect of dietary inclusion of soybean hull in the diet on digesta viscosity and fecal consistency during different phases.
Item |
Phases |
Control |
3% SH1 |
6% SH |
9% SH |
SEM |
P. value |
Gut viscosity (cp) |
1 |
5.33d |
5.50c |
5.63b |
5.83a |
0.02 |
0.019 |
2 |
5.35d |
5.55c |
5.67b |
5.88a |
0.04 |
0.004 |
|
3 |
5.36d |
5.48c |
5.59b |
5.78a |
0.01 |
0.003 |
|
Feces consistency2 |
1 |
1 |
1 |
2 |
2 |
- |
- |
2 |
1 |
1 |
2 |
2 |
- |
- |
|
3 |
1 |
1 |
2 |
2 |
- |
- |
Means in the same row with different superscripts are significantly different (P<0.05). 1SH= Abbreviated for soybean hull. 2For feaces consistency: 1, shows normal dry droppings and coning, while 2, show loose droppings, some coning, but no free water.
Table IV. Effect of dietary inclusion of soybean hull in the diet on hematology and serum biochemistry during different phases.
Parameters |
Control |
3% SH |
6% SH |
9% SH |
SEM |
P value |
Phase 1 |
||||||
RBCs (106μl) |
2.88 |
2.94 |
2.99 |
3.04 |
0.09 |
0.841 |
WBCs (103μl) |
3.13 |
3.04 |
3.01 |
2.99 |
0.19 |
0.967 |
PCV |
26.75 |
26 |
25 |
24 |
0.65 |
0.060 |
HB (g/dl) |
8.63 |
8.59 |
7.90 |
7.74 |
0.27 |
0.113 |
MCHC (g/dl) |
30.02 |
31.88 |
30.43 |
29.93 |
0.98 |
0.060 |
Parameters |
Control |
3% SH |
6% SH |
9% SH |
SEM |
P value |
MCV(fL) |
99.81 |
91.82 |
87.05 |
96.09 |
3.22 |
0.190 |
Total chol (mg/dl) |
120.81 |
120.05 |
118.96 |
117.9 |
1.78 |
0.727 |
HDL (mg/dl) |
80.54 |
79.65 |
79.47 |
80.49 |
1.27 |
0.063 |
LDL (mg/dl) |
24.49 |
27.80 |
25.34 |
23.65 |
1.39 |
0.265 |
VLDL (mg/dl) |
13.77 |
14.89 |
14.13 |
12.92 |
0.81 |
0.091 |
Heterophile (%) |
25.25 |
28.50 |
27.50 |
26.75 |
1.24 |
0.364 |
Lymphocyte (%) |
60.50 |
62.75 |
63.50 |
63 |
1.51 |
0.150 |
Hetrop:Lympho |
0.43 |
0.45 |
0.43 |
0.42 |
0.02 |
0.568 |
Protein (mg/dl) |
4.86 |
4.84 |
4.82 |
4.80 |
0.05 |
0.065 |
Phase 2 |
||||||
RBCs (106μl) |
2.69 |
2.66 |
2.54 |
2.49 |
0.06 |
0.274 |
WBCs (103μl) |
3.08 |
3.00 |
2.97 |
2.97 |
0.19 |
0.984 |
PCV |
28.25 |
27.75 |
26.50 |
26 |
0.7 |
0.145 |
HB (g/dl) |
10.02 |
9.80 |
9.53 |
9.36 |
0.30 |
0.545 |
MCHC (g/dl) |
36.26 |
37.18 |
37.62 |
36.4 |
1.96 |
0.998 |
MCV (fL) |
104.95 |
104.85 |
104.28 |
104.23 |
3.92 |
0.998 |
Total chol (mg/dl) |
117.7 |
116.4 |
116 |
115.2 |
2.08 |
0.065 |
HDL (mg/dl) |
78.47 |
77.35 |
75.16 |
75.2 |
1.48 |
0.063 |
LDL (mg/dl) |
25.22 |
25.34 |
23.47 |
22.85 |
1.16 |
0.444 |
VLDL (mg/dl) |
14.84 |
14.13 |
13.75 |
13.37 |
0.79 |
0.682 |
Heterophile (%) |
27.50 |
26.75 |
25.25 |
26 |
1.01 |
0.533 |
Lymphocyte (%) |
59.75 |
60.75 |
59.25 |
58 |
1.25 |
0.589 |
Heterop:Lympho |
0.44 |
0.44 |
0.42 |
0.44 |
0.01 |
0.860 |
Protein (mg/dl) |
4.70 |
4.69 |
4.68 |
4.66 |
0.30 |
0.904 |
Phase 3 |
||||||
RBCs (106μl) |
2.78 |
2.72 |
2.66 |
2.60 |
0.13 |
0.860 |
WBCs (103μl) |
3.11 |
3.06 |
3.03 |
3 |
0.14 |
0.968 |
PCV |
27.5 |
28.5 |
28 |
27 |
0.90 |
0.066 |
HB (g/dl) |
11 |
10 |
10.05 |
9.89 |
0.30 |
0.065 |
MCHC (g/dl) |
36.74 |
36.29 |
35.21 |
35.75 |
1.19 |
0.067 |
MCV(fL) |
108.4 |
102.41 |
106.9 |
111.3 |
5.93 |
0.284 |
Total chol (mg/dl) |
123.6 |
120.3 |
117.8 |
117.7 |
1.52 |
0.068 |
HDL (mg/dl) |
81.52 |
80.20 |
79.58 |
78.32 |
0.95 |
0.072 |
LDL (mg/dl) |
22.99 |
23.72 |
25.50 |
26.40 |
0.80 |
0.064 |
VLDL (mg/dl) |
16.07 |
16.38 |
14.60 |
14.12 |
0.79 |
0.203 |
Heterophile (%) |
29.5 |
28 |
26.5 |
25.75 |
1.04 |
0.107 |
Lymphocyte (%) |
56 |
55.75 |
56 |
58 |
2.35 |
0.550 |
Heterop:Lympho |
0.52 |
0.50 |
0.47 |
0.42 |
1.60 |
0.128 |
Protein (mg/dl) |
4.79 |
4.77 |
4.76 |
4.73 |
0.12 |
0.500 |
Means in the same row with different superscripts are significantly different (P<0.05). 1SH= Soybean hull. 2Abbreviation for: RBCs, red blood cells; WBC, white blood cells; PCV, packed cell volume; MCV, mean corpuscular volumes; MCHC, mean corpuscular hemoglobin concentration; HB, hemoglobin; HDL, high density lipoprotein; LDL, low density lipoprotein; VLDL, very low density lipoprotein.
Table V. Effect of dietary inclusion of soybean hull in the diet on histomorphology during different phases.
Phase |
Parameters |
Control |
3%SH1 |
6%SH |
9%SH |
SEM |
P value |
1 |
Duodenum villus |
||||||
Width (μm) |
72 |
85 |
81 |
78 |
4.51 |
0.292 |
|
Height (μm) |
621.7a |
610.7b |
597.7bc |
583.2c |
3.05 |
0.004 |
|
Crypt depth (μm) |
110.2a |
103.2b |
94bc |
85.7c |
3.45 |
0.041 |
|
Surface area (μm2) |
0.14 |
0.16 |
0.15 |
0.14 |
8.90 |
0.342 |
|
Jejunum villus |
|||||||
Width (μm) |
57.5 |
59.2 |
61.5 |
63.7 |
4.31 |
0.761 |
|
Height (μm) |
441.7 |
446.7 |
453.5 |
459.2 |
7.07 |
0.134 |
|
Crypt depth (μm) |
60.7 |
62.5 |
65.2 |
67.7 |
3.26 |
0.304 |
|
Surface area (μm2) |
0.082 |
0.085 |
0.087 |
0.090 |
6.25 |
0.493 |
|
Ileum villus |
|||||||
Width (μm) |
54.7 |
53.5 |
51.7 |
51 |
3.67 |
0.887 |
|
Height (μm) |
389.5a |
378.5ac |
368.2c |
345b |
7.15 |
0.006 |
|
Crypt depth (μm) |
50.75 |
48.75 |
48.25 |
47 |
2.97 |
0.844 |
|
Surface area (μm2) |
0.066 |
0.063 |
0.059 |
0.055 |
4.33 |
0.311 |
|
2 |
Duodenum villus |
||||||
Width (μm) |
93 |
106 |
102 |
99 |
4.51 |
0.292 |
|
Height (μm) |
642.7a |
631.7b |
618.7bc |
604.25c |
6.03 |
0.004 |
|
Crypt depth (μm) |
131.2b |
124.2a |
115ac |
99c |
5.33 |
0.006 |
|
Surface area (μm2) |
0.187 |
0.210 |
0.198 |
0.187 |
9.33 |
0.343 |
|
Jejunum villus |
|||||||
Width (μm) |
75.5 |
77.2 |
79.5 |
81.7 |
4.31 |
0.761 |
|
Height (μm) |
464.7 |
468.7 |
471.5 |
475.2 |
7.07 |
0.134 |
|
Crypt depth (μm) |
76.7 |
79.5 |
83.2 |
85.7 |
3.26 |
0.304 |
|
Surface area (μm2) |
0.112 |
0.115 |
0.118 |
0.121 |
6.60 |
0.437 |
|
Ileum villus |
|||||||
Width (μm) |
69.7 |
68.5 |
66.7 |
66 |
3.67 |
0.887 |
|
Height (μm) |
404.5a |
393.5ac |
383.2c |
360b |
7.16 |
0.006 |
|
Crypt depth (μm) |
65.7 |
63.7 |
63.2 |
62 |
2.97 |
0.844 |
|
Surface area (μm2) |
0.088 |
0.084 |
0.080 |
0.074 |
4.58 |
0.222 |
|
3 |
Duodenum villus |
||||||
Width (μm) |
110 |
123 |
119 |
116 |
4.51 |
0.292 |
|
Height (μm) |
677.7a |
666.7b |
653.7bc |
639.2c |
6.02 |
0.004 |
|
Crypt depth (μm) |
145.2a |
138.2c |
129bc |
120.7b |
5.56 |
0.041 |
|
Surface area (μm2) |
0.234 |
0.257 |
0.244 |
0.232 |
9.93 |
0.342 |
|
Jejunum villus |
|||||||
Width (μm) |
89.5 |
91.25 |
93.5 |
95.75 |
4.31 |
0.761 |
|
Height (μm) |
494.7 |
497.7 |
501.5 |
506.2 |
7.07 |
0.134 |
|
Crypt depth(μm) |
89.75 |
91.5 |
95.25 |
97.75 |
3.26 |
0.304 |
|
Surface area (μm2) |
0.140 |
0.143 |
0.147 |
0.151 |
7.08 |
0.409 |
|
Ileum villus |
|||||||
Width (μm) |
80.75 |
79.5 |
77.75 |
77 |
3.67 |
0.887 |
|
Height (μm) |
431.5c |
422.5ac |
415.2c |
407b |
7.15 |
0.006 |
|
Crypt depth (μm) |
81.75 |
79.75 |
79.25 |
78 |
2.97 |
0.844 |
|
Surface area (μm2) |
0.109 |
0.104 |
0.100 |
0.097 |
4.94 |
0.190 |
Means in the same row with different superscripts are significantly different (P<0.05). For abbreviations see Table IV.
lymphocytes ratio (H:L) and total protein concentration among all the groups. All the blood and serum biochemistry parameters were recorded in the normal range. The result regarding intestinal morphometric parameters is presented in Table V. During all phases, the 3% SH group had higher duodenal villus width and surface area than all other groups while duodenum villus height and crypt depth were (P<0.05) higher in the control group than in all SH containing diet groups. The jejunum morphological parameters were not affected during the entire period (P˃0.05). During all phases, the ileum villus width, crypt depth, and surface area were recorded as non-significant among all the groups. The villus height of the ileum in all phases was calculated (P<0.05) higher in the control group than in the 9% SH treatment group.
DISCUSSION
The effect of soybean hulls on digesta viscosity, fecal consistency, hematology, serum biochemistry, and intestinal morphometric parameters in laying hens during peak egg production period with three different periods (1, 2, and 3) were determined. The proximate analysis of feces showed a non-significant effect on the dry matter during all phases which is in line with the findings of Jarret et al. (2012) where a non-significant effect on feces dry matter was observed in swine-fed high fiber feed. The crude protein levels during phas1 and 2 were recorded (P<0.05) higher in SH-containing groups which is in agreement with the findings of Jarret et al. (2012) who recorded significantly higher nitrogen in feces of swine-fed high fiber feed. Soybean hulls containing treatment groups had (P<0.05) higher crude fiber (CF) and ash contents during phase-1 and 3 which is similar to the findings of Jarret et al. (2012) who described higher feces CF in swine fed high fiber feed than the control group. The low fiber digestibility which was recorded during the present study has possibly resulted in higher feces fiber excretion. Higher (P<0.05) crude fat contents in the control group than all SH treatment groups were recorded during all phases which are possibly due to the lower fat contents of the soybean hulls containing diets while the higher ash contents in feces of SH treatment groups is due to the comparatively higher DM contents of the feces of SH treatment groups than the control group. The viscosity of the intestinal contents during all phases was recorded (P<0.05) higher for the soybean hull containing diet groups which are similar to the findings of Tejeda and Kim (2021) who observed an increase in the intestinal viscosity for SH-containing diets during the entire rearing period for broiler when fed soybean hulls in the diet at the level of 8%. The findings of the present study are also in agreement with the statement of Langhout et al. (2000); Owusu-Asiedu et al. (2006); Tellez et al. (2014); Perera et al. (2019) that soluble fiber sources contain hygroscopic compounds (i.e., pectins, gums, and mucilages) with the ability to trap water and increase the viscosity of the digesta and cause changes in passage rate and nutrient absorption. Soybean hulls contain both soluble and insoluble water portions of fiber. The water-soluble portion of NSPs is notorious for forming a gel-like viscosity in the intestinal tract (Burnett, 1966; Gohl and Gohl, 1977). The water-soluble NSP fraction reduces or prolongs digesta passage rate through the intestinal tract due to its ability to form gel-like solid and thickened consistency and the feed consumption of young broilers declined (Salih et al., 1991; Almirall and Esteve, 1995) which is similar to the results observed in the present study. During phase-1 and 2, PCV had a higher value for the control group than SH containing treatment groups which are according to the result of Esonu et al. (2010) who in layer hen reported higher PCV in the control group than the group containing 30% soybean hull in feed. Total cholesterol during all phases was calculated (P<0.05) higher for the control group than all SH containing treatment groups which is similar to the report of He et al. (2015) who recorded lower total cholesterol in geese when fed different fibers source in feed as compared to control group with normal feed. Similarly, Mcnaughton (1978) stated that crude fiber inclusion in the diet reduces serum cholesterol levels and Regar et al. (2019) also reported lower cholesterol in broiler when fed different fiber sources (coffee pulp, Rice bran, and coconut oilcake) than that of the control group. The control group showed HDL during all phases which are in agreement with the findings of Regar et al. (2019) who reported higher HDL levels in the broiler for the control group compared to groups fed different fiber sources (coffee pulp, Rice bran, and coconut oilcake) in feed. The values of the hematological indices appeared similar to those earlier reported as normal for poultry. According to Esonu et al. (2010), the physiological responsiveness of the animal to its external and internal environment serves as a veritable tool for monitoring animal health and described that 30% inclusion of soybean hull (with/without supplementation enzyme) had no serious effect on the internal physiology of the layers. Similarly in the present study, it followed that up to 9% inclusion of soybean hull in the feed had no adverse effect on the internal physiology of the laying hens. All hematological and serum biochemistry values were recorded within the Thai indigenous chickens reference value range (Jain, 1993; Simaraks et al., 2004).
During all phases, the duodenum villus height and crypt depth were (P<0.05) higher in the control group than in all other SH treatments groups which is in agreement with the results of Tejeda and Kim (2020) who reported higher duodenum villus height in the broiler for the control group compared to 4, 6, and 8% Solka-floc (SF) and 4 and 6% SH in the feed while higher villus crept depth for the control group than that of SF (6 and 8%) and 4% SH in feed. During all phases, jejunum villus height, width, crypt depth, and surface area were not affected in all treatment groups which is in line with the report of, Tejeda and Kim (2020) where jejunum villus height was recorded as non-significant in broiler fed 4%SH in the feed while villus crypt depth was not affected in Solka-floc (4 and 8%) and soybean hull (8%SH) in feed. Similarly, Lai et al. (2015) in broiler reported non-significant jejunum villus height on supplementation of 0.5% FSBH (fermented soybean hull), 0.5% FSHP (Fermented soybean hull Pleurotus Eryngii), and 0.1% FSHP in feed. During all phases, the ileum villus height was (P<0.05) higher in the control group as compared to soybean hull diet groups which is in line with the result of Tejeda and Kim (2020) who documented higher ileum villus height in the broiler for the control group than both 8% SF and 8% SH in feed. Sadeghi et al. (2015) also reported shorter ileal villus height in broilers fed 3% sugar beet pulp in the diet than in the control and rice hull fed groups. Similar to the present study result, Tejeda and Kim (2020) in broiler recorded the highest ileal villus height for the control group compared to the 4 and 8% cellulose and SH containing feed groups. Contrary to the present study result, Lai et al. (2015) recorded significantly higher ileum villus height for 0.5% FSBH (fermented soybean hull), 0.5% FSHP (fermented soybean hull Pleurotus Eryngii), and 0.1% FSHP group than the control group. The impairment in the development of ileal villus could, therefore, be associated with the increase in bacterial activity that interferes with normal intestinal development (Pan and Yu, 2014). According to (Stein et al., 2008), the soybean hull contains 50% hemicellulose, 30% pectin, and 20% cellulose and the mix of different types of fibers appears to have a marked effect on intestinal morphology. Therefore, higher inclusions of such water-soluble carbohydrates reduce villus height in the ileum which might be associated with the lack of abrasive stimulus that is generally seen in such fibers compared with insoluble fibers (Rezaei et al., 2018). Anti-nutritional factors in soybean had been reported to have adverse effects on the morphology and function of digestive tracts in animals (Li et al., 1991). Furthermore, stressors that are present in the digesta can lead relatively quickly to changes in the intestinal mucosa due to the proximity of the mucosal surface and the intestinal content which is similar to the current study result for soybean hull groups having decreased intestinal villus and crypt depth height. Therefore, there is a possibility that the birds might have adapted to increasing levels of SH by increasing the passage rate through the digestive tract rather than increasing the size. However, this speculation needs further investigation. Any additional tissue turnover will increase nutrient requirements for maintenance, and will therefore lower the efficiency in terms of poor growth performance of the animal (Giannenas et al., 2010).
CONCLUSION
It is concluded that the effect of different levels of soybean hulls replacing soybean meal in the basal diet on various parameters was not adverse. Among soybean hulls treatment groups, the 3% and 6% SH diet group showed better effects for various parameters than that of the 9% SH group and the inclusion of this level will help to provide the least-cost feed ingredients to the poultry industry to generate revenue and provide quality protein in the form of eggs to common people with better/low prices.
ACKNOWLEDGMENTS
We acknowledge the staff of the Department of Poultry Science and Faculty of Animal Husbandry and Veterinary Science (FAHVS), The University of Agriculture, Peshawar Pakistan, and Sadiq Brother (SB) Company (Rawalpindi, Punjab) who provided technical and laboratory facilities.
Animal welfare statement
The experiment was approved by the ethical committee of the Faculty of Animal Husbandry and Veterinary Science, The University of Agriculture Peshawar, Pakistan
Funding
This study was financially supported by the Higher Education Commission (HEC) of Pakistan through (HEC Indigenous Scholarship) grant.
Statement of conflict of interest
The authors have declared no conflict of interest.
REFERENCES
Almirall, M., Francesch, M., Perez-Vendrell, A.M., Brufau, J., and Esteve-Garcia, E., 1995. The differences in intestinal viscosity produced by barley and β-glucanase alter digesta enzyme activities and ileal nutrient digestibilities more in broiler chicks than in cocks. J. Nutr., 125: 947-955.
AOAC, 2000. Official methods of analysis, Maryland, USA.
Bedford, M.R., and Classen, H.L., 1993. An in vitro assay for prediction of broiler intestinal viscosity and growth when fed rye-based diets in the presence of exogenous enzymes. Poult. Sci., 72: 137-143. https://doi.org/10.3382/ps.0720137
Burnett, G.S., 1966. Studies of viscosity as the probable factor involved in the improvement of certain barleys for chickens by enzyme supplementation. Br. Poult. Sci., 7: 55-75. https://doi.org/10.1080/00071666608415606
Campbell, T.W., 1995. Avian hematology and cytology. Iowa State University Press, Ames.Vol. 413
Castro Júnior, F.G., de Moura Camargo, J.C., de Castro, A.M.M.G., and Budiño, F.E.L., 2005. Fibra na alimentação de suínos. Bol. Indúst. Anim, 62: 265-280. http://www.iz.sp.gov.br/bia/index.php/bia/article/view/1297
Esonu, B.O., Iheshiulor, O., Chukwuka, O., Omede, A., and Ogbuewu, I., 2010. Performance characteristics and hematology of laying birds fed Safzyme supplemented soybean hull diet. Rep. Opin., 2: 16-21. http://www.sciencepub.net/report/report0208/03_3543report0208_16_21.pdf
Esonu, B.O., Izukanne, R.O., and Inyang, O.A., 2005. Evaluation of cellulolytic enzyme supplementation on production indices and nutrient utilization of laying hens fed soybean hull-based diets. Int. J. Poult. Sci., 4: 213-216. https://doi.org/10.3923/ijps.2005.213.216
Feng, J., Liu, X., Xu, Z.R., Wang, Y.Z., and Liu, J.X., 2007. Effects of fermented soybean meal on digestive enzyme activities and intestinal morphology in broilers. Poult. Sci., 86: 1149-1154. https://doi.org/10.1093/ps/86.6.1149
Giannenas, I., Pappas, I.S., Mavridis, S., Kontopidis, G., Skoufos, J., and Kyriazakis, I., 2010. Performance and antioxidant status of broiler chickens supplemented with dried mushrooms (Agaricus bisporus) in their diet. Poult. Sci., 89: 303-311. https://doi.org/10.3382/ps.2009-00207
Gobl, B., and Gohl, I., 1977. The effect of viscous substances on the transit time of barley digesta in rats. J. Sci. Fd. Agric., 28: 911-915. https://doi.org/10.1002/jsfa.2740281008
He, L.W., Meng, Q.X., Li, D.Y., Zhang, Y.W., and Ren, L.P., 2015. Meat quality, oxidative stability, and blood parameters from Graylag geese offered alternative fiber sources in growing period. Poult. Sci., 94: 750-757. https://doi.org/10.3382/ps/pev020
Henly, A.A., 1957. The determination of serum cholesterol. Analyst, 82: 286-287.
Ipharraguerre, I.R., and Clark, J.H., 2003. Soyhulls as an alternative feed for lactating dairy cows: A review. J. Dairy Sci., 86: 1052-1073. https://doi.org/10.3168/jds.S0022-0302(03)73689-3
Jain, N.C., 1993. Essential veterinary hematology. Lea and Febiger, Philadelphia. pp. 417.
Jarret, G., Cerisuelo, A., Peu, P., Martinez, J., and Dourmad, J.Y., 2012. Impact of pig diets with different fibre contents on the composition of excreta and their gaseous emissions and anaerobic digestion. Agric. Ecosyst. Environ., 160: 51-58. https://doi.org/10.1016/j.agee.2011.05.029
Khurshid, H., Baig, D., Jan, S. A., Arshad, M., and Khan, M.A., 2017. Miracle crop: the present and future of soybean production in Pakistan. MOJ Biol. Med., 2: 189-191. https://doi.org/10.15406/mojbm.2017.02.00042
Lai, L.P., Lee, M.T., Chen, C.S., Yu, B., and Lee, T.T., 2015. Effects of co-fermented Pleurotus eryngii stalk residues and soybean hulls by Aureobasidium pullulans on performance and intestinal morphology in broiler chickens. Poult. Sci., 94: 2959-2969. https://doi.org/10.3382/ps/pev302
Langhout, D.J., Schutte, J.B., De Jong, J., Sloetjes, H., Verstegen, W.A., and Tamminga, S., 2000. Effect of viscosity on digestion of nutrients in conventional and germ-free chicks. Br. J. Nutr., 83: 533-540. https://doi.org/10.1017/S0007114500000672
Li, D.F., Nelssen, J.L., Reddy, P.G., Blecha, F., Klemm, R.D., Giesting, D.W., and Goodband, R.D., 1991. Measuring suitability of soybean products for early-weaned pigs with immunological criteria. J. Anim. Sci., 69: 3299-3307. https://doi.org/10.2527/1991.6983299x
Lowry, O.H., Rosebrough, N.J., Farr, A.L., and Randall, R.J., 1951. Protein measurement with the Folin phenol reagent. J. biol. Chem., 193: 265-275. https://doi.org/10.1016/S0021-9258(19)52451-6
McNaughton, J.L., 1978. Effect of dietary fiber on egg yolk, liver, and plasma cholesterol concentrations of the laying hen. J. Nutr., 108: 1842-1848. https://doi.org/10.1093/jn/108.11.1842
Mielenz, J.R., Bardsley, J.S., and Wyman, C.E., 2009. Fermentation of soybean hulls to ethanol while preserving protein value. Bioresour. Technol., 100: 3532-3539. https://doi.org/10.1016/j.biortech.2009.02.044
Muir, W.M., Rogler, J.C., and Linton, D.D., 1985. Soymill feed as a fiber source to reduce energy intake in experimental diets. Nutr. Rep. Int., 32: 737-742.
Newkirk, R., 2010. Soybean: Feed industry guide. Canadian International Grains Institute, Canada, pp. 26-35.
Owusu-Asiedu, A.J.F.J., Patience, J.F., Laarveld, B., Van Kessel, A.G., Simmins, P.H., and Zijlstra, R.T., 2006. Effects of guar gum and cellulose on digesta passage rate, ileal microbial populations, energy and protein digestibility, and performance of grower pigs. J. Anim. Sci., 84: 843-852. https://doi.org/10.2527/2006.844843x
Pan, D., and Yu, Z., 2014. Intestinal microbiome of poultry and its interaction with host and diet. Gut Microbes, 5: 108-119. https://doi.org/10.4161/gmic.26945
Perera, W.N.U., Abdollahi, M.R., Zaefarian, F., Wester, T.J., Ravindran, G., and Ravindran, V., 2019., Influence of inclusion level of barley in wheat-based diets and supplementation of carbohydrate on growth performance, nutrient utilization, and gut morphometry in broiler starters. Br. Poult. Sci., 60: 736-748. https://doi.org/10.1080/00071668.2019.1639142
Regar, M.N., Tulung, B., Londok, J.J.M.R., Moningkey, S.A.E., and Tulung, Y.R.L., 2019. Blood lipid profile of broiler chicken as affected by a combination of Feed restriction and different crude fiber sources. IOP Conf. Ser. Earth Environ. Sci., 387: 012053. https://doi.org/10.1088/1755-1315/387/1/012053
Rezaei, M., Karimi Torshizi, M.A., Wall, H., and Ivarsson, E., 2018. Body growth, intestinal morphology, and microflora of quail on diets supplemented with micronized wheat fiber. Br. Poult. Sci., 59: 422-429. https://doi.org/10.1080/00071668.2018.1460461
Rojas, M.J., Siqueira, P.F., Miranda, L.C., Tardioli, P.W., and Giordano, R.L., 2014. Sequential proteolysis and cellulolytic hydrolysis of soybean hulls for oligopeptides and ethanol production. Ind. Crops Prod., 61: 202-210. https://doi.org/10.1016/j.indcrop.2014.07.002
Roland, S.R.D.A., and Caldwell, D., 1985. Relationship of calcium to wet droppings in laying hens. Poult. Sci., 64: 1809-1812. https://doi.org/10.3382/ps.0641809
Sadeghi, A., Toghyani, M., and Gheisari, A., 2015. Effect of various fiber types and choice feeding of fiber on performance, gut development, humoral immunity, and fiber preference in broiler chicks. Poult. Sci., 94: 2734-2743. https://doi.org/10.3382/ps/pev292
Salih, M.E., Classen, H.L., and Campbell, G.L., 1991. Response of chickens fed on hull-less barley to dietary β-glucanase at different ages. Anim. Feed Sci. Technol., 33: 139-149. https://doi.org/10.1016/0377-8401(91)90052-T
Simaraks, S., Chinrasri, O., and Aengwanich, W., 2004. Hematological, electrolyte and serum biochemical values of the Thai indigenous chickens (Gallus domesticus) in northeastern, Thailand. Songklanakarin J. Sci. Technol., 26: 425-430.
Stein, H.H., Berger, L.L., Drackley, J.K., Fahey, Jr, G.C., Hernot, D.C., and Parsons, C.M., 2008. Nutritional properties and feeding values of soybeans and their coproducts. In: Soybeans, AOCS Press. pp. 613-660. https://doi.org/10.1016/B978-1-893997-64-6.50021-4
Tejeda, O.J., and Kim, W.K., 2020. The effects of cellulose and soybean hulls as sources of dietary fiber on the growth performance, organ growth, gut histomorphology, and nutrient digestibility of broiler chickens. Poult. Sci., 99: 6828-6836. https://doi.org/10.1016/j.psj.2020.08.081
Tejeda, O.J., and Kim, W.K., 2021. Effects of fiber type, particle size, and inclusion level on the growth performance, digestive organ growth, intestinal morphology, intestinal viscosity, and gene expression of broilers. Poult. Sci., 100: 101397. https://doi.org/10.1016/j.psj.2021.101397
Tellez, G., Latorre, J.D., Kuttappan, V.A., Kogut, M.H., Wolfenden, A., Hernandez-Velasco, X., and Faulkner, O.B., 2014. Utilization of rye as energy source affects bacterial translocation, intestinal viscosity, microbiota composition, and bone mineralization in broiler chickens. Front. Genet., 5: 339. https://doi.org/10.3389/fgene.2014.00339
Vahouny, G.V., 1982. Dietary fibers and intestinal absorption of lipids. In: Dietary fiber in health and disease. Springer, Boston, MA., pp. 203-227. https://doi.org/10.1007/978-1-4615-6850-6_19
Walugembe, M., Rothschild, M.F., and Persia, M.E., 2014. Effects of high fiber ingredients on the performance, metabolizable energy and fiber digestibility of broiler and layer chicks. Anim. Feed Sci. Technol., 188: 46-52. https://doi.org/10.1016/j.anifeedsci.2013.09.012
Zak, B., 1957. Simple rapid microtechnique for serum total cholesterol. Am. J. clin. Pathol., 27: 583-588. https://doi.org/10.1093/ajcp/27.5_ts.583
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