Directory UMM :Data Elmu:jurnal:A:Animal Feed Science and Technology:Vol83.Issue3-4.Mar2000:

Animal Feed Science and Technology
83 (2000) 185±193

Blend of oil palm slurry and rice bran as feed
ingredient for broiler chickens
C.C. Atuahene, A. Donkoh*, I. Ntim
Department of Animal Science, University of Science and Technology, Kumasi, Ghana
Received 4 November 1998; received in revised form 2 June 1999; accepted 30 November 1999

Abstract
A 6-week feeding trial was conducted to assess the effect of four types of processed oil palm
slurry (OPS) using rice bran (RIB) as an absorbent, hereafter referred to as RIBROPS, to partially
replace maize on the growth performance of broiler chicks. Six hundred 14-day-old commercial
broiler chicks were randomly allocated to one of the ®ve dietary treatments. The dietary treatments
consisted of the control diet, which contained maize as the main energy source, and four other diets
each of which contained a ®xed amount of 100 g of one of the four types of RIBROPS kgÿ1. The
experimental diets were formulated to be both isoproteic and isoenergetic. Feed and water were
provided ad libitum for a period of 6 weeks.
The dietary treatments did not have signi®cant impact on feed intake (rˆÿ0.48), body weight
gain (rˆ0.42) and feed conversion ef®ciency (rˆÿ0.40). Carcass yields were similar. There were
no health-related problems attributable to the dietary treatments. Mortality was unaffected by the

dietary treatments. # 2000 Elsevier Science B.V. All rights reserved.
Keywords: Oil palm slurry; Rice bran; Growth performance; Chickens, Broilers

1. Introduction
In many developing countries there exists a largely untapped potential for utilising
feedstuffs for poultry. Among these is oil palm slurry (OPS), a by-product obtained
during the processing of the fruits of the oil palm (Elaeis guinensis) to obtain palm oil.
This ef¯uent is a potent pollutant (Davis, 1978). Olie and Tjeng (1971) indicated that it
has a Biological Oxygen Demand (BOD) of 20,000 ppm which is 100 times higher than
*

Corresponding author. Tel.: ‡233-51-60325.
E-mail address: pclab@ighmail.com (A. Donkoh).
0377-8401/00/$ ± see front matter # 2000 Elsevier Science B.V. All rights reserved.
PII: S 0 3 7 7 - 8 4 0 1 ( 9 9 ) 0 0 1 3 7 - 6

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C.C. Atuahene et al. / Animal Feed Science and Technology 83 (2000) 185±193

that of raw sewage. Its utilisation as an animal feed will minimise the pollution problem
as well as supply a cheap energy animal feed (Webb et al., 1977). Studies by Atuahene
et al. (1987) indicated the use of unprocessed OPS in broiler chicken diets allowed maize
levels to be signi®cantly reduced without affecting performance. However, because of its
high moisture content, OPS must be processed before it can be incorporated into poultry
feed formulations.
Many researchers have proposed different methods for treatment of the ef¯uent,
such as aerobic puri®cation and anaerobic digestion (Olie and Tjeng, 1971) as well as
biodegradation (Stanton, 1974). However, these are either impractical or uneconomical.
Webb (1975) therefore approached the problem of dehydration of the ef¯uent using
mechanically dried cassava meal and palm kernel meal as absorbent for the sludge.
In the study reported, herein rice bran was chosen for study as an absorbent as it is
currently available in large quantities in Ghana and is reported to contain low levels of
energy (Stilborn and Waldroup, 1990). This is aimed to develop a saleable by-product
from oil palm slurry and rice bran, by producing a high quality energy feedstuff for
poultry.
Regardless of its economic and nutritional status, it is essential that investigations of
the feeding potential of OPS should take cognizance of contaminants such as pathogenic
bacteria. The number and type of speci®c groups of microorganisms in a product
indicates the way it has been handled at all stages, post-harvest, for example, storage,

fermentation, processing, packaging and transportation. The level of spoilage
microorganisms can be used to predict the potential shelf-life of the product (Bainbridge
et al., 1996).
The objective of this study, therefore, was to assess the nutritive quality of resultant
four types of products from the combination of OPS and rice bran and the effect of
replacing a portion of the maize in broiler diets by the products (OPS plus rice bran in
different proportions) on growth performance. The kinds and numbers of the micro¯ora
present in fresh and processed oil palm slurry were also determined.

2. Materials and methods
2.1. Source of rice bran, oil palm slurry and processing method
The rice bran (RIB) used in the study was obtained as a by-product from local
rice mills in Kumasi, while the OPS was obtained from indigenous palm oil producers.
The slurry obtained was stored in a barrel and covered for 3 days. This allowed the
thickened slurry to settle on top leaving the aqueous layer underneath. The slurry was
then scooped, mixed with RIB in different proportions, sun-dried to a moisture content of
about 100±120 g kgÿ1 DM and then stored in sacks until used in formulations. The four
different proportions of OPS and RIB, hereafter referred to as `RIBROPS' were as
follows:
 RIBROPS I: 100 units of rice bran mixed with 25 units of OPS;

 RIBROPS II: 100 units of rice bran mixed with 50 units of OPS;

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C.C. Atuahene et al. / Animal Feed Science and Technology 83 (2000) 185±193
Table 1
Chemical composition (g kgÿ1 DM) of oil palm slurry and rice brana
Component

Oil palm slurry

Rice bran

Moisture
Crude protein
Ether extract
Crude ®bre
Ash
Calcium
Phosphorus

Metabolisable energy (MJ kgÿ1)

117.4
45.6
716.3
Trace
33.8
1.9
2.6
21.7

93.5
131.0
165.3
72.6
68.3
16.5
12.8
8.8

a

The values are the means of three samples.

 RIBROPS III: 100 units of rice bran mixed with 75 units of OPS;
 RIBROPS IV: 100 units of rice bran mixed with 100 units of OPS.
The chemical compositions of the oil palm slurry and rice bran are shown in Table 1.
2.2. Dietary treatments
Five experimental diets (Table 2) were formulated: a control diet, designated as dietary
treatment I, contained none of the RIBROPS and four others, designated as dietary
treatments II, III, IV and V, which contained a ®xed amount of 100 g RIBROPS I, II, III
and IV kgÿ1 diet, respectively. The experimental diets were formulated to be isoproteic
and isoenergetic.
2.3. Chemical analysis
Proximate analyses of the OPS, rice bran, the four types of RIBROPS and experimental
diets (dry matter, crude protein, ether extract, ash and crude ®bre) were analysed by
standard procedures (Association of Of®cial Analytical Chemists, 1990). Acid-detergent
®bre (ADF), neutral-detergent ®bre (NDF) and hemicellulose (Goering and van Soest,
1970) were also estimated on the four types of RIBROPS samples. Calcium and
phosphorus analyses followed the procedure of Fick et al. (1979). Sixteen 6-week-old

broiler chicks were used to determine the nitrogen-corrected true metabolisable energy
(TMEn) content of the four types of RIBROPS. Birds were fed ad libitum on a broiler
®nisher diet for 1 week prior to force-feeding (Sibbald, 1986). The birds were housed in
individual cages with collection trays, fasted for 24 h and force-fed 30 g of the test
ingredients. Eight broilers were kept fasted during the assay to measure endogenous
losses. Excreta were collected daily for 48 h after force-feeding, oven-dried at 608C for
48 h, equilibrated to ambient conditions, weighed and ground (Dale and Fuller, 1983).
The four types of RIBROPS and fecal samples were analysed for gross energy.
Metabolisable energy values for the experimental diets were, however, calculated from
values given by the National Research Council (NRC, 1994) and the determined TMEn
contents of the RIBROPS.

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C.C. Atuahene et al. / Animal Feed Science and Technology 83 (2000) 185±193

Table 2
Composition of diets fed to 14-day-old broiler chickens
Dietary treatments
I (Control)

II

III

IV

V

590
0
190
60
130
20
5
4
1

490

100
190
60
130
20
5
4
1

490
100
190
60
130
20
5
4
1

490

100
190
60
130
20
5
4
1

490
100
190
60
130
20
5
4
1

220.3

33.6
36.3
15.2
8.2
11.59

225.0
39.0
41.0
15.3
9.5
11.48

225.6
39.7
41.0
15.6
9.5
11.51

225.8
40.0
42.0
15.7
9.6
11.55

226.4
40.3
42.5
15.9
9.6
11.58

ÿ1

Ingredients (g kg )
Maize
RIBROPSa
Fish meal
Soyabean meal
Wheat bran
Oyster shell (ground)
Vitamin and mineral premixb
Salt (NaCl)
Allzyme PTc
Chemical analysis (g kgÿ1 DM)
Crude protein
Crude ®bre
Ether extract
Calcium
Phosphorus
MEn (MJ kgÿ1)

a
The ratio of rice bran (RB) to oil palm slurry (OPS) in RIBROPS incorporated in diets II, III, IV and IV are
100:25; 100:50; 100:75 and 100:100, respectively
b
Premix supplied (kgÿ1 diet): Vitamin A, 10,000 IU; Vitamin D3, 2000 IU; Vitamin E, 10 IU; Vitamin K,
3 mg; ribo¯avin, 2.5 g; cobalamin, 0.05 mg; pantothenic acid, 5 mg; niacin, 12.5 mg; choline, 175 mg; folic
acid, 0.5 mg; Mg, 2.8 mg; Fe, 0.5 mg; Cu, 50 mg; Zn, 25 mg; Co, 62.5 mg.
c
A proprietary feed enzyme complex derived from the fungus Aspergillus niger (Alltech, Kentucky, USA).
Allzyme PT, added to diets at 1 kgÿ1 ton, contains xylanase and pentosanase (600 XU gÿ1). Other carbohydrases
present include galactomannase, betaglucanase, cellulase, hemicellulase and pectinase.

2.4. Microbiological procedure
Samples of fresh, homogenised oil palm slurry were taken for surface viable microbial
counts and isolation (Bainbridge et al., 1996) and identi®cation (ICMSF, 1978
International Commission on Microbiological Speci®cations for Food). For microbial
count and isolation, 10 g of OPS were inoculated onto selective agar (Nutrient agar
for bacteria, MacConkey agar for coliforms and Sabouraund agar for fungi), and the
plates were incubated at 378C for 48 h. The number of colonies on the agar was counted.
Plates supporting approximately 30±300 colonies were counted and the mean of duplicate
plates noted. If growth was present after incubation, colonies were selected for
identi®cation. These procedures involved examination of colonial characteristics,
morphology, motility, staining and biochemical properties using the guidelines of
ICMSF (1978). Ten grams (10 g) each of the four types of RIBROPS samples were
homogenised and diluted in 90 ml sterile maximum recovery diluent to obtain 110ÿ1
suspensions. The diluted suspensions of the four types of RIBROPS were subjected in the
same way to surface microbial counting and microbial isolation as the fresh samples of
OPS.

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189

2.5. Experimental animals and management
A total of 600 unsexed 14-day-old commercial broiler chickens (Hybro strain), with an
average initial body weight of 0.22 kg, were allotted randomly to the ®ve dietary
treatments, in a completely randomised design. Each treatment, consisting of 120 birds,
was replicated three times. The birds were placed and reared in deep litter pens. The
study was conducted for 42 days (2±8 weeks of age). Before the start of the feeding trial
the birds were weighed and subsequently allocated to the treatments in such a way that
the mean weights differed as little as possible. Birds had free access to feed and water.
2.6. Parameters measured
Body weight gain, feed consumption and feed conversion ef®ciency (feed:gain ratio)
were determined weekly for individual replicates of each dietary treatment. Records of
mortality were also kept. All sick and dead chickens were sent to the Veterinary
Laboratory for post-mortem examination. At 56 days of age, four broilers from each of
the 15 replicates were selected at random, starved of feed for about 18 h to empty their
crops, killed by cutting the jugular vein, exsanguinated, defeathered and eviscerated.
Carcass yield was calculated from eviscerated weight and liveweight.
2.7. Histological studies
At 56 days of age, the possible deleterious effects of RIBROPS on liver were also
assessed. Four chickens from each treatment were randomly selected, killed by cervical
dislocation, the liver excised and examined to determine whether the diets had resulted
in any gross pathological changes. Liver sections were cut before staining with
haematoxylin and eosin (Humason, 1979) and examined microscopically for any
abnormalities in the cells.
2.8. Statistical analysis
Data were subjected to linear regression analysis of variance using the General Linear
Models procedure of Statistical Analysis Systems (1987). Differences among means were
determined by the t-test (Steel et al., 1997) and considered signi®cant if P 0:05†

where X is the level of OPS fraction of RIBROPS in the diet.
In general, there was no substantial difference in mean body weight gain during the
period of 2±8 weeks of age between birds fed the control diet and the RIBROPS
containing diets. The ef®ciency with which feed was converted to gain (feed: gain ratios)
was also unaffected by dietary treatments. Comparing the performance of birds fed the
four RIBROPS-containing diets, the highest rate of gain, though non-signi®cant was
observed in birds fed RIBROPS IV-containing diet (i.e. dietary treatment V). This may be
due to the high content of OPS fraction of RIBROPS in the diet. Earlier study (Atuahene
et al., 1987) showed that a corresponding increase in the OPS level resulted in faster
weight gains. The following correlations between the level of OPS fraction of RIBROPS
in the diet and weight gain and feed conversion ratio were found:
Y…weight gain† ˆ 1:97…0:091† ‡ 0:0001…0:00005†X
Y…feed : gain† ˆ 1:89…0:24† ‡ 0:0005…0:00003†X

…r ˆ 0:42; P > 0:05†
…r ˆ ÿ0:40; P > 0:05†:

Likewise, the carcass yields of broiler chickens fed diets with or without RIBROPS were
similar. This observation is similar to that of Webb et al. (1977). The level of OPS
fraction of RBROPS in the diet gave a correlation coef®cient of ÿ0.22 when linearly
regressed against carcass yield indicating OPS exerted no signi®cant impact on this
parameter.
A total of 10 mortality cases were recorded during the experimental period (Table 5).
The mortality values were rather variable and show no trends that can be attributed to
RIBROPS. Out of the 10 mortality cases, three (2.5%) each occurred among birds fed on
the control and RIBROPS III-containing diets, two (1.67%) from the RIBROPS Icontaining diet and one (0.83%) each from those on the other remaining RIBROPS
containing diets. Post-mortem autopsies indicated no speci®c causes for deaths.
The ®ndings, under the conditions of this study, showed no toxic effects in terms of
gross tissue changes in the liver. The histological characteristics of the liver from birds on
the control diet were similar to those from birds on RIBROPS based diets.
Based on results obtained with the by-products tested in this study, it is concluded that
RIBROPS is a suitable alternative energy source to be investigated in greater detail.
Acknowledgements
The authors thank Gyedu-Baah Apanin and T. Edusei for technical assistance, M.
Pobee of the Faculty of Pharmacy, UST for microbial analysis, P.Wallace of the Animal

C.C. Atuahene et al. / Animal Feed Science and Technology 83 (2000) 185±193

193

Research Institute of Ghana for the chemical analysis and Ms. Gladys Ndziba for her
secretarial assistance. We acknowledge the ®nancial support of the National Agricultural
Research Project of the Council for Scienti®c and Industrial Research of Ghana for
conducting this study.

References
Association of Of®cial Analytical Chemists, 1990. Of®cial Methods of Analysis, 15th Edition. AOAC,
Arlington, Virginia, USA.
Atuahene, C.C., Donkoh, A., Swatson, H., 1987. Oil palm slurry (OPS) as partial replacement for maize in the
diets of broiler chickens. Anim. Feed Sci. Technol. 17, 157±162.
Bainbridge, Z., Tomlins, K., Wellings, K., Westby, A., 1996. Methods for assessing quality characteristics of
non-grains starch staples, Part 3. Laboratory methods. Natural Resources Institute, Chatham, UK.
Dale, N.M., Fuller, H.L., 1983. Oven drying vs. freeze drying of excreta in true amino acid availability and true
metabolizable energy assay. Poult. Sci. 62, 1407±1408, (Abstr.).
Davis, J.B., 1978. Palm oil mill ef¯uent: a review of methods proposed for its treatment. Trop. Sci. 20, 233±262.
Fick, K.R., McDowell, L.R., Miles, P.H., Wilkinson, N.S., Funk, J.D., Conrad, J.H., 1979. Methods of Mineral
Analysis for Plant and Animal Tissues, 2nd Edition. Department of Animal Science, University of Florida,
Gainesville, USA.
Goering, H.K., van Soest, P.J., 1970. Forage ®bre analysis (apparatus, reagents, procedures and some
applications). Agriculture Handbook No. 379, Agriculture Research Service. United States Department of
Agriculture, Washington DC, USA, p. 20.
Humason, G.L., 1979. Animal Tissue Techniques, 4th Edition. Freeman, San Francisco, CA, USA, p. 661.
International Commission on Microbiological Speci®cations for Foods (ICMSF), 1978. Microorganisms In
Foods 1. Their Signi®cance and Methods of Enumeration, 2nd Edition. University of Toronto Press, Toronto,
Canada.
Jacobs, B.M., Gestein, M.J., 1968. A Handbook of Microbiology. Van Nostrand, Princeton.
Mertens, D.R., 1985. Recent concepts useful in optimizing nutrition of dairy cows. In: The 1985 Proc.
Minnesota Nutr. Conf. Minnesota, pp. 99±123.
National Research Council, 1994. Nutrient Requirements of Domestic Animals. Nutrient Requirements of
Poultry, 9th revised Edition. National Academy Press, Washington, DC., USA.
Olie, J.J., Tjeng, T.D., 1971. Treatment and disposal of palm oil ef¯uent. Oil Palm News 10/11, 23±24.
Salle, A.J., 1961. Fundamental Principles of Bacteriology, 5th Edition. McGraw-Hill, New York.
Sibbald, I.R., 1986. The TME system of feed evaluation: Methodology, feed composition data and bibliography.
Animal Research Center Contribution 85±19, ON, Canada.
Stanton, W.R., 1974. Treatment of ef¯uent from palm oil factories. The Planter 50, 382±387.
Statistical Analysis Systems Institute Inc., 1987. Procedures Guide for Personal Computers, Version, 6 Edition.
SAS Institute, Cary, NC.
Stilborn, H.L., Waldroup, P.W., 1990. An evaluation of low-energy feedstuffs in diets for laying hens. Anim.
Feed Sci. Technol. 27, 327±339.
Steel, R.G.D., Torrie, J.H., Dickey, D.A., 1997. Principles and procedures of statistics. A Biometrical Approach,
3rd Edition. McGraw-Hill, New York.
Webb, B.H., 1975. Potential process for utilisation of agro-industrial waste for production of food. UMAGA/
FAUM Food Conference 1975, Reprint No. 36.
Webb, B.H., Hutagalung, R.I., Cheam, S.T., 1977. Palm oil mill waste as animal feed. In: Earp, D.A., Newall, W.
(Eds.), Processing and Utilisation. International Development in Palm Oil, Malaysia, pp. 125±145.
Zindel, H.C., 1970. Bacteriological procedures. Michigan State University Agricultural Experiment Station
Research Report 117, 45±46.