THE INCREASE OF PROTEIN DIGESTIBILITY AND METABOLIZABLE ENERGY OF RICE BRAN BYSACCHAROMYCES CEREVISIAE
FERMENTATION
I.G.N.G. BIDURA, I. P. SUYADNYA, D.A. WARMADEWI, D.P.M.A. CANDRAWATI, I.A.P.UTAMI, N.L.P. SRIYANI, AND I. G. A. I. ARYANI
Faculty of Animal husbandry, Udayana University, Denpasar-Bali e-mail: bidura_unud@yahoo.com
ABSTRACT
Yeast culture product, which have some fermentation ability consist of yeast (S. cereviseae) and the media which the yeast grew on. This research was carried out to study the increase of protein digestibility and metabolizable energy of rice bran byS. cereviseae fermentation. The research used a completely randomized design (CRD) with four treatments in six replicates. There were four birds in each replicate with relative homogenuous body weight. The experimental basal diets for the experiment period were formulated to 15% unfermented rice bran as a control diet (A), diets with 15% fermented rice bran by 0,10% S. cereviseae (B), diets with 15% fermented rice bran by 0,20% S. cereviseae (C), and diets with 15% fermented rice bran 0,30% S. cereviseae (D), repectively. Experimental diets and drinking water were provided ad libitum during the entire experimental period. The results of this experiment showed that used of 15% fermented rice bran by S. cereviseae (B, C, and D treatments) in diets were increased significantly different (P<0,05) on body weight gains and feed efficiencies of Bali drake than control groups (A). For using of 15% fermented rice bran by S. cereviseae before were offered for the bird were increased significantly different (P<0,05)t on protein digestibility and metabolizable energy of rice bran than without fermented treatments or control group (A). It is concluded that used ofS. cereviseae for fermenting rice bran were increased protein digestibility, metabolizable energy, and performance of Bali drake aged 0-8 weeks.
Key words: S. cereviseae, rice bran, metabolizable energy, protein digestibility, Bali drake
INTRODUCTION
Alternative feed sourches include milling and distillery by-products as well as
forages, and are acceptable energy sources for poultry. The potensial of forages as energy
sources for poultry depends considerably on such factors as cell wall content, degree of
microbial fermentation in the large intestine, and extent of absorption and utilization of the
volatile acids produced (Kahliqueet al., 2003). Agro-industry by-product as well as rice bran, is one such product abundantly and cheaply available during the season. These toxic
factors are trypsin inhibitor, lectin (hemagglutinin), phytic acid as phytate, and crude fiber.
These anti-nutritive factors have been reported to reduce feed intake and depress
Bach Knudsen (2001) reported that dietary fiber (DF) has been defined as the
complex macromoleculer substances in food plants that are not degraded by mammalian
digestive enzymes. With the exception of lignin, all of the materials called DF are
carbohydrates in nature. DF is thought to mediate protective effects on the colonic
epithelium through their fermentation products and fecal bulking capacity (Wang et al., 2003).
Feeding high fiber resulted in a lowered rate of lipogenesis and tendency of an
increased capacity to utilize acetyl-CoA in pigs (Zhu et al., 2003). Non starch polysaccharide (NSP) are the carbohydrate components of DF and are the predominant
substrates for anaerobic fermentation. NSP can, to a certain degree, be broken down by
microflora permanently colonizing the gastrointestinal tract and their breakdown in all
nonruminant including humen ang pig mainly occurs in the hindgut by microbial
fermentation (Wenget al., 2003).
Most of the recent studies focus on the effect of the bacterial and fungal enzymes
used in rice bran based diets. More than 50% of phosphorus in rice bran is in the form of
phytate, which is poorly available in the digestive tract of monogastric animals (Ilyaset al., l995). Phytic acid found in vegetable feed sources affect the protein and amino acid
digestibilities negatively by preventing the activities of the proteolytic enzymes such as
pepsin/trypsin. Futhermore, phytic acid has a higher P content and chelating ability and so
phytate form of phytic acid diminishes the availability of Ca and P (Pointillart, 1991).
Monogastric animals can not make use of phytin phosphorus due to lacking of phytase
enzyme in their digestive systems and consequently phytin posphorus is mostly excreted
in the faeces.
Therefore, it is susgested that fermented of feeding by yeast (S. cerevisiae) can be
used in order to alleviate the negative effect of phytic acid. The use of S. cerevisiae as a
probiotics sourches in poultry production as become an area of great interest, because
continued use of probiotics in animal feeds may result in the presence of antibiotics
residues in animal products. Gut microfloral enzymes are beneficial to the nutrition of the
host because they increase the digestion of nutrients, especially in the lower intestine
(Sissons, 1989). Previous experiments showed that the inclusion of microorganisms in the
diets improved feed efficiency and digestibility (Sucianiet al.,2011 and Warmadewiet al., 2008).
belong to the Ascomycoyina subdivision and have many industrial applications in the brewing, destilling, and baking industries (Ahmad, 2005).
Park et al. (l994) showed that yeast added to a diet could reduce animal wastes. But, Piaoet al. (l999) reported no significant improvement in weight gain, feed intake and
feed efficiency with 0,10% yeast culture. Feeding live yeast to broiler breeder reduced
colonization of salmonela in their ceca and improved posphorus utilization in growing
chickens.
The objective of this study was to determine the increase of protein digestibility
and metabolizable energy of rice bran by S. cereviseae fermentation and performance of Bali drake.
METERIAL AND METHOD
Management of experimental Birds
One hundred twente of Bali drake day-old-duck (DOD) were randomly allotted to
colony wire-floored cages, 5 birds per cages. A 500 ml plastic muge/bottle equipped was
placed of each cage. Experimental diets and drinking water were provided ad libitum during the entire experimental period (for a 8-week period). Body weight and feed intake
were recorded weekly.
Diet and Drinking Water
The four experimental diets (Table 1) based on corn-rice bran were formulated to
15% unfermented rice bran as a control diet (A), diets with 15% fermented rice bran by
0,10%S. cereviseae (B), diets with 15% fermented rice bran by 0,20% S. cereviseae(C), and diets with 15% fermented rice bran 0,30% S. cereviseae (D), repectively. The basal diets (Table 1) were formulated to meet or exceed nutrient requirement (NRC, 1994). All
of diets in mash form and compiled by iso-energy (2900 kcal ME/kg) and iso-protein (CP:
18%). Through all the experimental period, birds were allowed ad libitum acces to feed
and water. The composition of ration compiler substances and nutrient which is used in
diets can be seen in Table 1.
Saccharomyces cereviseae
Fermented of Rice Bran
Fermented of rice bran were prepared from the same batch approximately 0.0-0.3%
Saccharomyces cerevisiaewere added to each feeding. Following the fermentation, water was added to bring the product to 50% content and fermented for 3 days. After
fermentation, fermented of rice bran was dried at 450C for 6 h.
Tabel 1. Formula and chemical composition of diets of growing Bali drake aged 0-8 weeks (as-fed basis)1)
Ingredient
(%)
Level ofS.cerevisiaein Rice Bran Fermented2)
0% (A) 0.1% (B) 0.2% (C) 0.3% (D)
Yellow corn 53,95 53,95 53,95 53,95
Rice bran 10,00 10,00 10,00 10,00
Fish meal 13,05 13,05 13,05 13,05
Coconut meal 13,60 13,60 13,60 13,60
Soybean 8,00 8,00 8,00 8,00
Palm oil 0,50 0,50 0,50 0,50
NaCl 0,40 0,40 0,40 0,40
Mineral mix 0,50 0,50 0,50 0,50
Total 100 100 100 100
Metabolizable Energy (kkal/kg) 2902 2902 2902 2902 29003)
Crude Protein ( % ) 18,0 18.0 18.0 18.0 18.003)
Crude Fibre ( % ) 4.85 4.85 4.85 4.85 5-73)
Eter Extract ( % ) 6.76 6.76 6.76 6.76 5-103)
Ca ( % ) 1.08 1.08 1.08 1.08 0.9-1.23)
P-available ( % ) 0.63 0.63 0.63 0,63 0.403)
Argynin ( % ) 1.52 1.52 1,52 1.52 1.003)
Lysine ( % ) 1.31 1.31 1.31 1.31 0.823)
Metyonine+systeine ( % ) 0.79 0.79 0.79 0.79 0.603)
Note:
1. Calculation based ingredient by Scottet al. (1982) 2. Level ofS.cerevisiaeon Rice Bran Fermentedin rations 3. Standard of Farrell (1995)
Retention and excretion of nutrients.
After of feeding trial, 6 birds from each treatment were randomly assigned to
individual metabolic cages to determine the retention and excretion of dietary nutrients.
collected excreta were removed before drying at 600C for 48 h and subsequent grinding.
Feed and feces were analyzed by AOAC (l994) procedures for proximate components.
The retention of nutrients was calculated by dividing the amount of retained nutrient
(ingested nutrient minus excreted nutrient) by the amount of ingested.
Dry matter (DM), organic matter (OM), CP and CF determinations were done
according to the Assocciation of Official Analytical Chemists (l994). The CP content of
the diets was determined using the Kjeldahl procedure (AOAC, 1994). Crude fibre in the
feeds were determined using the procedure of Van Soest et al. (l991) on oven-dried samples.
Statistical Analysis
All data were subjected to a one-way analysis of variance test (Steel and Torrie,
1980). Statistical significances among treatment means were determined by method of
New Multiple Range Test of Duncan when the F value was significant at 5 % level.
RESULTS AND DISCUSSION
Table 2 shows the chemical composition of unfermented rice bran (UF) and
fermented rice bran (F) ingredient. The digestibility both of crude protein and and
metabolizable energy (ME) were slightly increased significantly different (P<0,05) by
S.cerevisiaefermentation.
Table 2. The effect ofS. cerevisiaefermented on nutrient digestibilities (% dry matter) and metabolizable energy of rice bran
Digestibility of Rice Bran Level ofS. cerevisiaein Rice Bran Fermented1)
0% (A) 0.1% (B) 0.2% (C) 0.3% (D)
Crude protein (%) 66.71b2) 72.95a 73.62a 73.26a
Crude fiber (%) 46.79a 48.51a 47.98a 48.06a
Metabolizable Energy (kcal/kg) 1723b 1849a 1901a 1870a
Note:
1. Level of S.cerevisiae on rice bran fermented in rations: 0.0% (A); 0.1% (B); 0.2% (C), and 0.3% (D), repectively.
2. The different superscript at the same row is significantly different (P<0,05)
S. cerevisiae can not effect on crude fiber digestibility of rice bran. Becouse, among the cell wall polysaccharides of rice bran known as nonstarch polysaccharides
enzymitically in the digestive systems of the birds due to the lacking of enzymes degrading
the NSPs in their digestive systems (Choct, 2002).
The metabolizable energy on birds were offered fermented rice bran was increased
significantly (P<0,05) different than metabolizable energy on birds were offered
unfermented rice bran (Table 2).
Final Body Weight and Live Weight Gains
Weight gain, feed intake, and feed efficiency are given in Table 3. At the end of
the experiment (at 56 days of age) the body weight gain was significantly (P<0.05)
increased in the group fed with fermented rice bran by S. cerevisiae diet compared to groups that received control (unfermented rice bran). In general the body weight gain
tended to increase with increasing levels ofS. cerevisiae which is probably due to increase of crude protein digestibility and metabolizable energy of the fermented rice bran used in
experiment (Biduraet al., 2009).
Table 3. Addition effect of fermented rice bran byS. cerevisiaein diets on performance of Bali drake eged 0-8 weeks
Variabel Level ofS. cerevisiaein Rice Bran Fermented1)
SEM2
0% (A) 0.1% (B) 0.2% (C) 0.3% (D)
Final body weight (g/birds) 974.36b3) 1067.09a 1105.72a 1098.43a 25.902
Body weight gains (g/birds/8 weeks) 974.62b 1004.41a 1041.60a 1035,71a 20.937
Feed consumption (g/birds/8 weeks) 5633.30a 5283.20a 5301.74a 5344.26a 215.08
Feed Conversion Ratio (feed/gains) 5.78a 5.26b 5.09b 5.16b 0.148
Note :
1. Level of S.cerevisiae on rice bran fermented in rations: 0.0% (A); 0.1% (B); 0.2% (C), and 0.3% (D), repectively.
2. Standard Error of The Treatment Means
3. The different superscript at the same row is significantly different (P<0,05)
For the body weight gain there was no significantly (P>0.05) difference between
the 0.1% and 0.3% S. cerevisiae levels, but they were significantly lower in the group
control (A). This finding was consistent with previous results reported by Caoat al. (l998). The average of final body weight during eight weeks observation at birds which
having the ration control (A) is 974.36 g/birds (Table 3). The average of final body weight
Feed Consumption and Feed Conversion
Feed consumption was not affected by fermented rice bran in diets. The averages
of feed consumption in all of treatment were not significantly different (P>0,05) than
control groups. Feed conversion ratio were significantly different (P<0,05) between
unfermented rice bran and fermented rice bran. Feed consumption was not affected by
fermented feed (FF) in diets. The averages of feed consumption between in treatments B,
C, and D were not significantly different (P>0,05) than control groups.
Feed conversion ratio and live weight gains in control groups are lower
significantly (P<0.05) difference than other groups. This may be coused by the fact that
poultry can not utilize the fibrous parts of the rice bran ingredients.
The average of feed conversion ratio (feed : gains) during eight weeks observation
at birds which having the ration control (A) is 5.78/birds (Table 3). The average of feed
conversion ratio (feed : gains) of the birds having ration FF were decreased significantly
(P<0,05) than control groups.
Table 3 shows the chemical composition of unfermented rice bran and fermented
rice bran ingredient. The digestibility of crude protein, crude fiber, and ME were slightly
increased by the fermentation. These results indicated that carbohydrates other than fibres
were used for microbial growth (Saccharomyces cerevisiae) and the reduction of nitrogen
free extract resulted in increased concentration of the other components. Yi et al. (l996) reported that supplementation of microbial in diets improved N retention in broiler
chickens and in vitro digestibility of vegetable protein. Also, Chen et al. (2005) reported that addition of 0.20% complex probiotic (L. acidophilus and S. cerivisae) in basal diets were inceased digestiblities of dry matter.
Fermented of rice bran ingredient by ragi (Saccharomyces cereviseae) and it’s
addition to the diet had better digestibilities, because Saccharomyces cereviseae in the
gastrointestinal tract can part of an probiotics sourches. Saccharomyces cereviseaeas part of an probiotics were increased retention of mineral Calsium, Posphor, and Mangane
(Nahashon et al., l994 dan Piao et al., l999). Also, Piao et al. (l999); Sibbald and Wolynetz (l986), suggested that probiotics in the gastro intestinal tract can improve protein
and energy retention on the body of birds. These fungal are effective in degrading of the
complex compounds such as b-glucans and arabinoxylans (Bedford and Classen, 1992).
According to Ilyas et al. (l995), when the fermented feeding was suplemented in formula feeds, phytase in the fermented product might partly degrade the phytate in order
protein source of feed, which contains high available phosphorus. It’s was reported that
fermentation of soybean meal byAspergillus usamireduced phytate phosphorus levels. Fermentation process by ragi which contains Saccharomyces cerevisiae, according to Wallace dan Newbold (1993), Saccharomyces cerevisiae can improve crude fibre
digestibility on the ceca of birds to become volatile fatty acid (acetate, provionate, and
butirate acid).
Ilyas et al. (l995) reported if the enzyme effectively degrades phytase in the digestive tract, phytase in fermented rice bran can be degraded phytate from other
ingredients of ration. The reasons for the reduction both of excreta protein and energy by
the feeding fermentations may be related to the fact that fermentation process may improve
dietary protein and energy digestibility (Chiang dan Hsieh, 1995). Jaelani et al. (2008), reported that fermented of palm kernel meal byTrichoderma reeseiwas increased both of metabolizable energy and crude protein contents of palm kernel meal.
Chen et al. (2005) reported that dietary supplementation of complex probiotic increased the body weight gain and decreased fecal NH3-N concentration, and slightly
improved digestibility of nutrients. Fermented feed product to the rations coused numerical
increases in the body weight gain. This study is consistent with some studies which
indicated that fermented diets effect performance positively (Bidura et al. 2008b). This case can be attributed to the positive effects of fermented feed product on phytates and
protein. Wuet al. (2005) reported that supplementation ofAspergillus xlanasecan improve the performance of the broilers fed the wheat-based diet.
Piao et al. (l999) reported that used of 0.10% yeast (Saccharomyces cerevisae) in diets were increased body weight gains, feed efficiency, and absorption of nutrient in
broiler, and were decreased N and P excretion in manure. Parket al. (l994) suggested that body weight gain and feed efficiencies were significantly improve by the addition of
0.10% yeast culture in diets of broiler. Bidura (2008) reported that birds were offered fermented diets coaused body weight dan carcass weight of drake were increased.
It is concluded that used ofS. cereviseae for fermenting rice bran were increased protein digestibility, metabolizable energy, and performance of Bali drake aged 0-8 weeks.
ACKNOWLEDGEMENTS
The authors are entirely grateful for the chemical analyses of sample by staff of
authors also want to thank to Rector and Head of LPPM Udayana University for funding
this research.
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