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The Effect of Giving Probiotics and Palm Kernel Meal Subjected to Enzymatic Hydrolysis with Mannanase on Broiler Growth Performance



Mairizal , Fahmida Manin and Ella Hendalia
 
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ABSTRACT

Background and Objective: Palm kernel meal is a byproduct of processing palm oil that can be used as animal feed. Palm kernel meal contains mannan in sufficiently high quantities that its use is limited to poultry. Enzymatic hydrolysis of palm kernel cake with the enzyme mannanase produces mannose and mannooligosaccharides (MOS), which can act as prebiotics. Prebiotics are used for the growth of probiotic microbes in the digestive tract of broilers. Probiotics are living microorganisms that are given in sufficient quantities and provide beneficial effects to the health of livestock while being able to increase livestock production. This study aimed to examine the effect of probiotics and palm kernel meal hydrolyzed with mannanase enzymes on broiler growth performance. Materials and Methods: This study used a completely randomized 3×6 factorial design with 3 replicates. The first factor was 3 doses of probiotics through the drinking water (0, 1 and 2%) and the second factor was 6 ration levels of palm kernel cake after hydrolysis with mannanase enzymes (0, 10, 15, 20, 25 and 30%). The variables observed included feed consumption, body weight gain, feed conversion ratio and mortality. Results: The supply of up to 30% palm kernel meal after enzymatic hydrolysis in broiler rations did not significantly influence (p>0.05) feed consumption, body weight gain and feed conversion ratio. Probiotic administration to the level of 2% through the drinking water also showed no significant effect (p>0.05) on feed consumption, body weight gain and feed conversion ratio but showed a significant effect (p<0.05) on mortality. The provision of 1 and 2% probiotics can reduce mortality compared to feed without probiotics. The interaction between the administration of palm kernel meal after enzyme hydrolysis and the administration of probiotics showed no significant effect (p>0.05) on all the observed parameters. Conclusion: Based on these results, it can be concluded that the administration of up to 30% palm kernel meal after enzyme hydrolysis has no negative effects in broiler rations. Probiotic administration to the level of 2% also had no negative effects on broiler growth performance and did not reduce survival. There was no interaction between the palm kernel meal and probiotics on broiler growth performance.

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Mairizal , Fahmida Manin and Ella Hendalia, 2019. The Effect of Giving Probiotics and Palm Kernel Meal Subjected to Enzymatic Hydrolysis with Mannanase on Broiler Growth Performance. Pakistan Journal of Nutrition, 18: 997-1003.

DOI: 10.3923/pjn.2019.997.1003

URL: https://scialert.net/abstract/?doi=pjn.2019.997.1003
 
Copyright: © 2019. This is an open access article distributed under the terms of the creative commons attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

INTRODUCTION

Palm kernel meal (PKM) is a by-product of the process of separating palm kernel oil chemically (extraction) or physically (expeller) and contains nutrients that are useful as animal feed. PKM can be used in rations as a source of protein because the crude protein content can reach 14.5-19.6%1. The use of PKM in poultry rations is limited because of the high content of crude fiber (12-16%) and grittines2 and the low content of the amino acids, methionine, tryptophan and cystine3.

Palm kernel meal contains fiber that is high in non-starch polysaccharides (NSP) and β-mannan. Abdollahi et al.4 reported that almost 96% of the total NSP in PKM was in the form of insoluble NSP. Saenphoom et al.5 stated that content of β-mannan in PKM is 58%. The high content of nonstarch polysaccharides found in PKM increases intestinal viscosity, thereby reducing nutrient absorption6.

Mannan absorption in poultry is very limited because there is no mannanase enzyme in the digestive tract of poultry. The addition of enzymes is one way to reduce the negative effects of mannan by increasing t he availability of nutrients in poultry rations. Hydrolysis of mannan polysaccharides with the help of enzymes reduce antinutrient factors and intestinal viscosity, release nutrients from cell walls and break down mannan into simple sugars, allowing nutrients and digestive enzymes to move more freely and increase nutrient absorption7.

Hydrolysis of PKM with exogenous enzymes can reduce the components of cellulose, hemicellulose and lignin and can increase reducing sugars5, while hydrolysis using mannanase enzymes can reduce cellulose, hemicellulose and crude fiber content in PKM8-10. The hydrolysis of PKM with mannanase enzyme from Streptomyces cyaenus produces manno-oligosaccharides (MOS) predicted as mannobiose, mannotriose, mannotetrosa, mannopentosa, mannohexose and mannoheptose11. Manno-oligosaccharides are nondigestible oligosaccharides and could be potentially applied as dietary fiber and prebiotics12.

Prebiotics are mixtures of indigestible oligosaccharides, consisting of three to ten carbohydrate monomers that may promote growth, colonization, or activity of the probiotic microorganisms in the gut13. A variety of molecules can be prebiotics but the majority are dietary fibers, such as oligosaccharides14. Studies have shown that prebiotics affect feed efficiency by improving the height and number of goblet cells in the jejunum of broiler chickens15 and influence the gut immune system via stimulation of the specific bacteria metabolism14. Probiotics and prebiotics can increase body weight, carcass weight and mortality rates in broiler chickens16,17. Thus, probiotics and prebiotics have been suggested as alternatives to antibiotics in animal production18,19. Probiotic containing Lactobacillus species provide resistance to the host against disease causing agents, such as E. coli, Salmonella, Campylobacter and Eimeriaa cervulina 20.

Mannanase enzyme hydrolysis of PKM is expected to support greater levels of PKM in broiler rations and act as a prebiotic source for probiotic microbes. Therefore, it is necessary to conduct a study to measure the effect of probiotics and hydrolyzed PKM supplementation on the performance of broiler chickens.

MATERIALS AND METHODS

Production of mannanase crude enzyme extract: The enzyme used in this study came from the crude extract of the mannanase enzyme produced from Bacillus cereus V9 with enzyme activity of 29.5 UI mL1 21. Bacillus cereus V9 bacteria were rejuvenated by growing in mannan liquid media with a composition of 0.5% locus bean gum (LBG), 0.05% yeast extract, 0.075% peptone and Mendels and Sternberg minerals22. Then, Bacillus cereus V9 was incubated in a shaker incubator for 88 h at room temperature with a rocking speed of 130 rpm22. Crude Mannanase extract was obtained by means of culture samples centrifuged at a speed of 12,000 rpm for 15 min at 4°C so that they were separated from the supernatant and pellet. The supernatant obtained was a crude extract of the mannanase enzyme and was then used to hydrolyze PKM.

Hydrolysis of PKM with mannanase enzyme from Bacillus cereus V9: The PKM used in this study came from PT Kurnia Tunggal Nugraha Jambi, Indonesia. PKM is first ground so that the particle size decreased without filtration. Enzyme filtrate was added to PKM with a ratio of 1 mL for each gram of PKM by spraying enzyme filtrate evenly on the PKM substrate and then incubated at room temperature for 5 h9.

Research design: This study used a 3×6 factorial completely randomized design (CRD) with 3 replicates. The first factor was 3 doses of probiotic lactic acid consisting of Lactobacillus fermentum, Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophillus23,24 through the drinking water (0, 1 and 2%) and the second factor included 6 levels of hydrolyzed PKM (0, 10, 15, 20, 25 and 30%). The composition, nutrient (%) and energy (kcal kg1) content of the treatment ration are listed in Table 1.

Table 1:
Composition, nutrient and energy of treatment rationing
1Palm kernel meal Hydrolysis, 2Content (per kg of ration); Vitamin A: 2,500 IU, Vitamin D: 3,500 IU, Vitamin E: 1.5 IU, Vitamin K3: 0.4 mg, Thiamine: 0.3 mg, Riboflavin: 1 mg, Pyridoxine: 1 mg, Cyanocobalamin: 2.4 μg, Vitamin C: 6 mg, Niacin: 7 mg, Calcium-d-pantothenate: 1 mg, Manganese: 20 mg, Iron: 5 mg, Iodine: 0.04 mg, Zinc: 20 mg, Cobalt: 0.04 mg, Copper: 0.6 mg, Antioxidant: 2 mg, Methionine: 7 mg and Lysine: 7 mg, 3Metabolism energy

Drinking water and rations were given ad libitum in 540-day-old chicks for 5 weeks of maintenance. The variables observed included ration consumption, body weight gain, feed conversion ratio and mortality.

Statistical analysis: All data were analyzed using 2-way analysis of variance (ANOVA) based on a 3×6 factorial design. If a significant main effect was found (p<0.05), then any differences were assessed using Duncan's Multiple Range Test (DMRT)25.

RESULTS AND DISCUSSION

The effect of probiotics and the use of palm kernel meal hydrolyzed by mannanase enzyme on ration consumption, body weight gain and feed conversion ratio can be seen in Table 2.

Effect of diet on feed consumption: Based on the results of analysis of variance, the administration of probiotics and PKM hydrolyzed with mannanase enzymes and their interaction, had no significant effect (p>0.05) on the feed consumption of broiler chicken. In Table 2, it can be seen that the administration of hydrolyzed PKM to a level of 30% in the ration does not affect the consumption of feed. The results of this study indicate that the hydrolysis of PKM with mannanase enzymes can improve nutritional quality. Mairizal et al.9 reported that hydrolysis of PKM using the mannanase enzyme from Bacillus cerus V9 with an enzyme activity of 29,500 UI kg1 could reduce the crude fiber content from 16.78-9.68%. The hydrolysis of PKM with the mannanase enzyme from Penicillium italicum at a dose of 23,112 UI kg1 decreased the crude fiber content by 64.02%8 and the mannanase enzyme from Aspergillus terreus K1 at a dose of 9,000 UI kg1 reduced the crude fiber content from 21. 99-13.40%10.

Crude fiber of PKM contains high amounts of mannan5. Several studies have shown that enzymatic hydrolysis using β-mannanase significantly increases the content of mannose and mannan-oligosaccharides from PKM11,26. Mannose and mannan-oligosaccharides from enzymatic PKM hydrolysis can function as prebiotics for broilers. Prebiotics are a source of nutrition for good bacteria, such as Lactobacillus and Bifidobacteria and increase the populations of beneficial bacteria in the digestive tracts of broiler chickens. Nevertheless, the results of this study indicate that there is no relationship (p>0.05) between the administration of probiotics by giving PKM after hydrolysis with the mannanase enzyme with feed consumption of broiler chicken. This result is likely due to ineffective use of the prebiotics in hydrolyzed palm kernel meal by the probiotic lactic acid bacteria.

Table 2:
Average feed consumption, body weight gain, feed conversion ratio and mortality of broiler chickens fed probiotics and palm kernel meal from enzyme hydrolysis
a,bDifferent letters in the same column show a significant effect (p<0.05)

Wang et al.27 reported that mannan oligosaccharides (MOS) are not considered to be the direct substrate used for fermentation by microbes. However, MOS can inhibit growth of gram-negative pathogenic bacteria by offering competitive binding sites28.

Probiotic administration of lactic acid bacteria (Lactobacillus fermentum, Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophilus) to a level of 2% did not reduce feed consumption. Probiotic administration aims to balance the microbial population in the digestive tract of broilers. Probiotics are not important nutrients for livestock, so they will not affect the consumption of rations. According to Adams and Moss29, feed additives, or “feed additive” or “nutricine”, are ingredients that are mixed into feed that can affect the health and nutritional conditions of livestock, even though they are not nutrients. Similar results, namely, that the administration of probiotics does not affect the consumption of feed, were also reported by Khaksefi and Ghoorchi30, Timmerman et al.31, Jung et al.32 and Mansoub33.

Effect of diet on body weight gain: Including hydrolyzed PKM in rations showed no significant effect (p>0.05) on body weight increase in broiler chickens. Broiler chickens provided rations containing 30% hydrolyzed PKM had an average body weight of 1,146.25 g, which was not different from the average body weight of chickens with rations that did not contain hydrolyzed palm kernel cake (1,145.08 g). The research ration was formulated to be isoprotein and isoenergic, so it did not affect body weight gain. Previous research also reported that ioscaloric and isoprotein rations containing PKM did not have a negative effect on broiler chickens growth34. Supplementation of exogenous enzymes into broiler diets containing PKM to improve growth performance has been reported by Yahya et al.35, Iyayi and Davies36 and Sekoni et al.37. The results of this study prove that the hydrolysis of PKM with mannanase enzyme can reduce anti-nutritional factors in the form of fibers, especially from nonstarch polysaccharides so as not to affect broiler performance. High NSP intake can increase digesta viscosity in the digestion of broilers, thus inhibiting enzyme contact with digesta, which results in low digestibility of starch, fat and protein38-41.

Probiotic administration to the level of 2% through the drinking water (P2) did not show a significant effect (p<0.05) on the weight gain of broiler bodies. Probiotics can only play a role in improving the health status of livestock but have not been shown to play a role in increasing the digestibility of nutrients. The results of this study are in line with those reported by Awad et al.42 that the addition of probiotics to broilers did not show a significant effect on body weight compared to the control group. Similarly, Appelt et al.43 found that the addition of prebiotics did not significantly influence the weight gain of broiler chickens

Effect of diet on feed conversion ratio: Providing rations with hydrolyzed PKM had no significant effect (p>0.05) on feed conversion ratio. Broiler chickens who were given rations containing as much as 30% enzyme-hydrolyzed PKM had the same feed conversion ratio as the control ration (0% PKM Hydrolysis). This result is because the research ration was formulated to be isoprotein and isoenergic (Table 1) so that it did not affect feed consumption or body weight gain. High-quality feed that is palatable and balance protein and energy will result in low feed conversion ratio44. Increased nutrient digestibility of PKM enzyme-hydrolyzed as a result of reduced crude fiber content likely causes a decrease in viscosity of the digesta so as not to affect feed conversion ratio. Sundu and Dingle2 stated that the addition of enzymes in rations containing PKM can reduce digesta viscosity by 27% when compared with no enzyme administration.

The provision of probiotics to a level of 2% did not to reduce feed conversion ratio, with or without rations containing enzyme-hydrolyzed PKM. Giving probiotics only increases the health status of livestock by balancing the microflora in the digestive tract but has not been shown to increase absorption of food substances. Mountzouris et al.45 stated that probiotics can change mucin movements and microbial populations in the chicken's small intestine, so that their presence can improve intestinal function and health, improve the composition of the caecal microflora and increase absorption of nutrients. The results of this study are in line with those reported by Mutus et al.46 and Vargas-Rodriguez et al.47 who stated that the administration of probiotics did not increase feed consumption, body weight gain or feed conversion ratio in broilers.

Mortality: Probiotics showed a significant effect (p<0.05) on mortality over 35 days of maintenance, whereas the supply of hydrolyzed PKM and its interaction with the administration of probiotics showed no significant effect (p>0.05) on mortality. The mortality rate during the study based on treatment is presented in Table 2. The highest mortality rate was found in the treatment without probiotics, which was 6.67%, while probiotic administration at 1% (2.2%) and at 2% (1.67%) were not significantly different (p>0.05) in terms of mortality. The mortality observed in this study is in line with Awad et al.42 who stated that the broiler mortality rate was lower for the group supplemented with probiotics when compared to the mortality rate for the group without probiotics. Jin et al.48 stated that the addition of probiotics in broiler feed can increase endurance so that mortality is low.

The results of this study indicate that palm kernel cake can be optimized in broiler rations after being pretreated with enzymatic hydrolysis. Probiotic administration of lactic acid bacteria can only reduce mortality but cannot increase the weight gain of broiler bodies

CONCLUSION

PKM after enzyme hydrolysis can be added to a level of 30% in broiler rations. Probiotic administration to the level of 2% did not have a negative effect on broiler growth performance and reduced mortality. There was no interaction between the provision of enzyme-hydrolyzed palm kernel meal and the provision of probiotics to improve broiler growth performance.

ACKNOWLEDGMENTS

This research was funded by DIPA PNBP LP2M Universitas Jambi Number: SP-DIPA-042.01.2.400950/2018 dated December 5, 2017, in accordance with the Research Contract Number: 2657/UN21.17/LT/2018. Authors are very grateful to the Rector of Universitas Jambi and the head of the Universitas Jambi research and community service institution (LPPM) who have allowed the implementation of this research.

REFERENCES
1:  Alimon, A.R., 2004. Nutritive value of palm kernel cake for animal feed. Palm Oil Dev., 40: 12-14.
Direct Link  |  

2:  Sundu, B. and J. Dingle, 2003. Use of enzymes to improve the nutritive value of palm kernel meal and copra meal. Queensland Poult. Sci. Symp., 11: 1-15.
Direct Link  |  

3:  Fasuyi, A.O., S.O. Abiodun and O.T. Akomolafe, 2014. Bioconversion and enzymes fortification of palm kernel meal as protein supplement in broiler rations. Am. J. Exp. Agric., 4: 767-784.
CrossRef  |  Direct Link  |  

4:  Abdollahi, M.R., B.J. Hosking, D. Ning and V. Ravindran, 2016. Influence of palm kernel meal inclusion and exogenous enzyme supplementation on growth performance, energy utilization and nutrient digestibility in young broilers. Asian-Aust. J. Anim. Sci., 29: 539-548.
Direct Link  |  

5:  Saenphoom, P., J.B. Liang, Y.W. Ho, T.C. Loh and M. Rosfarizan, 2011. Effect of enzyme treatment on chemical composition and production of reducing sugars in palm (Elaeis guineenis) kernel expeller. Afr. J. Biotechnol., 10: 15372-15377.
Direct Link  |  

6:  Ng, W.K., 2004. Researching the use of palm kernel cake in aquaculture feeds. Palm Oil Dev., 41: 19-21.
Direct Link  |  

7:  Latham, R.E., M. Williams, K. Smith, K. Stringfellow, S. Clemente, R. Brister and J.T. Lee, 2016. Effect of β-mannanase inclusion on growth performance, ileal digestible energy and intestinal viscosity of male broilers fed a reduced-energy diet. J. Applied Poult. Res., 25: 40-47.
CrossRef  |  Direct Link  |  

8:  Olaniyi, O.O., 2014. Effect of beta-mannanase treatment on nutritive quality of palm kernel meal. Afr. J. Microbiol. Res., 8: 2405-2410.
Direct Link  |  

9:  Mairizal, F. Manin and E. Hendalia, 2018. Performans ayam broiler yang diberi Probio_ FM dan bungkil inti sawit hasil hidrolisis dengan enzim mannanase yang diproduksi dari Bacillus cereus V9. Laporan Penelitian Dosen Senior LPPM Universitas Jambi, Indonesia.

10:  Chen, W.L., M.F. Jahromi, S.C.L. Candyrine, J.B. Liang, N. Abdullah and Z. Idrus, 2018. Enzymatic hydrolysis drastically reduces fibre content of palm-kernel expeller, but without enhancing performance in broiler chickens. Anim. Prod. Sci., (In Press). 10.1071/AN17860

11:  Purnawan, A., Y. Yopi and T.T. Irawadi, 2017. Production of manooligomannan from palm kernel cake by mannanase produced from streptomyces cyaenus. Biosaintifika: J. Biol. Biol. Educ., 9: 73-80.
CrossRef  |  Direct Link  |  

12:  Yopi, A. Purnawan, A. Thontowi, H. Hermansyah and A. Wijanarko, 2006. Preparasi mannan dan mannanase kasar dari bungkil kelapa sawit. Jurnal Teknologi, 4: 312-319.
Direct Link  |  

13:  Erdogan, Z., S. Erdogan, O. Aslantas and S. Celik, 2010. Effects of dietary supplementation of synbiotics and phytobiotics on performance, caecal coliform population and some oxidant/antioxidant parameters of broilers. J. Anim. Physiol. Anim. Nutr., 94: E40-E48.
CrossRef  |  Direct Link  |  

14:  Gourbeyre, P., S. Denery and M. Bodinier, 2011. Probiotics, prebiotics and synbiotics: Impact on the gut immune system and allergic reactions. J. Leukocyte Biol., 89: 685-695.
CrossRef  |  Direct Link  |  

15:  Baurhoo, B., L. Phillip and C.A. Ruiz-Feria, 2007. Effects of purified lignin and mannan oligosaccharides on intestinal integrity and microbial populations in the ceca and litter of broiler chickens. Poult. Sci., 86: 1070-1078.
CrossRef  |  Direct Link  |  

16:  Brzoska, F., S. Buluchevskij, K. Stecka and B. Sliwinski, 2007. The effects of lactic acid bacteria and mannan oligosaccharide, with or without fumaric acid, on chicken performance, slaughter yield and digestive tract microflora. J. Anim. Feed Sci., 16: 241-251.
Direct Link  |  

17:  Kathirvelan, C., D. Premchandar, M.R. Purushothaman, P. Vasanthakumar and D. Chandrasekaran, 2012. Study on synergistic effects of non starch polysaccharides NSP degrading enzyme, probiotic and prebiotics supplementation on broiler performance. Int. J. Agric. Biosci., 1: 20-22.
Direct Link  |  

18:  Alkhalf, A., M. Alhaj and I. Al-Homidan, 2010. Influence of probiotic supplementation on blood parameters and growth performance in broiler chickens. Saudi J. Biol. Sci., 17: 219-225.
CrossRef  |  Direct Link  |  

19:  Saad, N., C. Delattre, M. Urdaci, J.M. Schmitter and P. Bressollier, 2013. An overview of the last advances in probiotic and prebiotic field. J. Food Sci. Technol., 50: 1-16.
CrossRef  |  Direct Link  |  

20:  Dalloul, R.A., H.S. Lillehoj, T.A. Shellem and J.A. Doerr, 2003. Enhanced mucosal immunity against Eimeria acervulina in broilers fed a Lactobacillus-based probiotic. Poult. Sci., 82: 62-66.
CrossRef  |  Direct Link  |  

21:  Mairizal, Y. Marlida, Mirzah and F. Manin, 2018. Isolation and characterization of mannanase-producing Bacillus cereus isolated from the Hindgut of Termites. Pak. J. Nutr., 17: 116-123.
CrossRef  |  Direct Link  |  

22:  Mandels, M. and D. Sternberg, 1976. Recent advances in cellulase technology. J. Ferment. Technol., 54: 267-286.
Direct Link  |  

23:  Manin, F., E. Hendalia and A. Aziz, 2007. Isolasi dan produksi isolat bakteri asam laktat dan Bacillus sp dari saluran pencernaan ayam buras asal lahan gambut sebagai sumber probiotik. J. AGRITEK (J. Ilmu-ilmu Pertanian Teknol. Pertanian Kehutanan), 15: 74-78.

24:  Manin, F., 2012. [The potency of Lactobacillus acidophilus and Lactobacillus fermentum from digestive tract of local chickens growing in peat soil as probiotic sources]. J. Ilmiah Ilmu-Ilmu Peternakan, 13: 221-228, (In Indonesian).
Direct Link  |  

25:  Steel, R.G.D. and J.H. Torrie, 1980. Principles and Procedures of Statistics: A Biometrical Approach. 2nd Edn., McGraw Hill Book Co., New York, USA., ISBN-13: 9780070609266, Pages: 633.

26:  Navidshad, B., J.B. Liang, M.F. Jahromi, A. Akhlaghi and N. Abdullah, 2016. Effects of enzymatic treatment and shell content of palm kernel expeller meal on performance, nutrient digestibility and ileal bacterial population in broiler chickens. J. Applied Poult. Res., 25: 474-482.
CrossRef  |  Direct Link  |  

27:  Wang, X., Y.Z. Farnell, E.D. Peebles, A.S. Kiess, K.G.S. Wamsley and W. Zhai, 2016. Effects of prebiotics, probiotics and their combination on growth performance, small intestine morphology and resident Lactobacillus of male broilers. Poult. Sci., 95: 1332-1340.
CrossRef  |  Direct Link  |  

28:  White, L.A., M.C. Newman, G.L. Cromwell and M.D. Lindemann, 2002. Brewers dried yeast as a source of mannan oligosaccharides for weanling pigs. J. Anim. Sci., 80: 2619-2628.
CrossRef  |  Direct Link  |  

29:  Adams, M.R. and M.O. Moss, 2000. Food Microbiology. 2nd Edn., Royal Society of Chemistry, University of Surrey Guildford, UK.

30:  Khaksefidi, A. and T. Ghoorchi, 2006. Effect of probiotic on performance and immunocompetence in broiler chicks. J. Poult. Sci., 43: 296-300.
CrossRef  |  Direct Link  |  

31:  Timmerman, H.M., A. Veldman, E. van den Elsen, F.M. Rombouts and A.C. Beynen, 2006. Mortality and growth performance of broilers given drinking water supplemented with chicken-specific probiotics. Poult. Sci., 85: 1383-1388.
CrossRef  |  Direct Link  |  

32:  Jung, S.J., R. Houde, B. Baurhoo, X. Zhao and B.H. Lee, 2008. Effects of galacto-oligosaccharides and a Bifidobacteria lactis-based probiotic strain on the growth performance and fecal microflora of broiler chickens. Poult. Sci., 87: 1694-1699.
CrossRef  |  Direct Link  |  

33:  Mansoub, N.H., 2010. Effect of probiotic bacteria utilization on serum cholesterol and triglycrides contents and performance of broiler chickens. Global Vet., 5: 184-186.
Direct Link  |  

34:  Yeong, S.W., T.K. Mukherjee and R.I. Hutagalung, 1981. The nutritive value of palm kernel cake as a feedstuff for poultry. Proceedings of the National Workshop on Oil Palm By-Product Utilization, December 14-15, 1981, Kuala Lumpur, Malaysia, pp: 100-107.

35:  Yahya, M., K. Azhar, F.Y. Chin, A.B. Idris and N. Vincent, 2000. Use of commercial enzyme to improve utilization of palm kernel expeller meal in poultry diets. Proceeding of the 22nd Malaysian Society of Animal Production Annual Conference, May 29-June 1, 2000, Kota Kinabalu, Malaysia, pp: 155-156.

36:  Iyayi, E.A. and B.I. Davies, 2005. Effect of enzyme supplementation of palm kernel meal and brewer's dried grain on the performance of broilers. Int. J. Poult. Sci., 4: 76-80.
CrossRef  |  Direct Link  |  

37:  Sekoni, A.A., J.J. Omage, G.S. Bawa and P.M. Esuga, 2008. Evaluation of enzyme (Maxigrain®) treatment of graded levels of Palm Kernel Meal (PKM) on nutrient retention. Pak. J. Nutr., 7: 614-619.
CrossRef  |  Direct Link  |  

38:  Annison, G. and M. Choct, 1991. Anti-nutritive activities of cereal non-starch polysaccharides in broiler diets and strategies minimizing their effects. World's Poult. Sci. J., 47: 232-242.
CrossRef  |  Direct Link  |  

39:  Mathlouthi, N., J.P. Lalles, P. Lepercq, C. Juste and M. Larbier, 2002. Xylanase and β-glucanase supplementation improve conjugated bile acid fraction in intestinal contents and increase villus size of small intestine wall in broiler chickens fed a rye-based diet. J. Anim. Sci., 80: 2773-2779.
PubMed  |  Direct Link  |  

40:  Centeno, M.S.J., P.I.P. Ponte, T. Ribeiro, J.A.M. Prates and M.A.L. Ferreira et al., 2006. Galactanases and mannanases improve the nutritive value of maize and soybean meal based diets for broiler chicks. J. Poult. Sci., 43: 344-350.
CrossRef  |  Direct Link  |  

41:  Amerah, A.M., C. Gilbert, P.H. Simmins and V. Ravindran, 2011. Influence of feed processing on the efficacy of exogenous enzymes in broiler diets. World's Poult. Sci. J., 67: 29-36.
CrossRef  |  Direct Link  |  

42:  Awad, W.A., K. Ghareeb, S. Abdel-Raheem and J. Bohm, 2009. Effects of dietary inclusion of probiotic and synbiotic on growth performance, organ weights and intestinal histomorphology of broiler chickens. Poult. Sci., 88: 49-56.
CrossRef  |  PubMed  |  Direct Link  |  

43:  Appelt, M.D., R.V. Nunes, P.C. Pozza, W.T.M. da Silva, I. Venturi and C.G.V. Nunes, 2010. [Levels of probiotics in animal and vegetal origin feed for broilers]. Rev. Bras. Zootec., 39: 765-771, (In Portuguese).
CrossRef  |  Direct Link  |  

44:  Anggorodi, R., 1995. Poultry feed science progress advanced. Fakultas Peternakan, Institut Pertanian Bogor, Bogor.

45:  Mountzouris, K.C., P. Tsirtsikos, E. Kalamara, S. Nitsch, G. Schatzmayr and K. Fegeros, 2007. Evaluation of the efficacy of a probiotic containing Lactobacillus, Bifidobacterium, Enterococcus and Pediococcus strains in promoting broiler performance and modulating cecal microflora composition and metabolic activities. Poult. Sci., 86: 309-317.
CrossRef  |  PubMed  |  Direct Link  |  

46:  Mutus, R., N. Kocabagli, M. Alp, N. Acar, M. Eren and S.S. Gezen, 2006. The effect of dietary probiotic supplementation on tibial bone characteristics and strength in broilers. Poult. Sci., 85: 1621-1625.
CrossRef  |  Direct Link  |  

47:  Vargas-Rodriguez, L.M., L.A. Duran-Melendez, J.A. Garcia-Masias, J.L. Arcos-Garcia, B.M. Joaquin-Torres nd M.G. Ruelas-Inzunza, 2013. Effect of probiotic and population density on the growth performance and carcass characteristics in broiler chickens. Int. J. Poult. Sci., 12: 390-395.
CrossRef  |  Direct Link  |  

48:  Jin, L.Z., Y.W. Ho, M.A. Ali, N. Abdullah, K.B. Ong and S. Jalaludin, 1996. Adhesion of Lactobacillus isolates to intestinal epithelial cells of chicken. Lett. Applied Microbiol., 22: 229-232.
CrossRef  |  Direct Link  |  

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