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Int.J.Curr.Microbiol.App.Sci
(2015)
4(
4
): 48
-61
48
Review
Article
Extrusion of Feed/Feed Ingredients and Its Effect on Digestibility and
Performance
of Poultry: A Review
Muhammad Aziz Ur Rahman
1
, Abdul Rehman
2
, Xia Chuanqi
1,
Zhang Xing Long
1,
Cao Binghai
1*, Ji Linbao1
and
Su Huawei3
1
Department of Animal Nutrition and Feed Technology, College of Animal Science, China
Agricultural University, Beijing
, China
2
Department of Animal Sciences, University College of Agriculture, University
of Sargodha,
Sargodha, Pakistan
3
Institute of Animal Science, Ch
inese Academy of Agricu
ltural Sciences, Beijing, China
*Corresponding author
A B S T R A C T
I
ntroduction
Feed cost contributes a large proportion of
the total cost in commercial poultry bird
production
(
Khattak
et al., 2006). In feed
production to gain maximum production
from the chicken, not only ingredients
contributes the higher amount of the total
cost but feed processing also contribute a
huge cost (Beukovi
et al., 2010
;
Gracia
et
al.
, 2010
;
Wu
and
Ravindran, 2004). Feed
processing techniques have both pos
itive
and
negative effect on digestibility
and
animal performance which affect the
profitability of
production
(Al-
Marzooqi
and
Wiseman, 2009
;
Buchanan
et al.,
2010
;
Liu
et al.,
2013
). To improve the nutritional
value of the ingredients and feed different
processing techniques are being used (Liu et
al., 2013). In recent years the extrusion
technique is extensively used in feed of
animals, because this technology has
numerous advantages, including the
possibility of wide application, high
ISSN: 2319
-7706
Volume
4
Number
4
(201
5
) pp. 48
-61
http://
www.ijcmas.com
In modern poultry farming system the major emphasis is on reducing the feed cost
by adopting modern processing techniques and by enhancing feed efficiency.
Extrusion process is one of the best processing techniques not only to enhance the
nutritional value of the ingredients and feed but also efficiency of the feed. In
modern feed milling operations, extrusion is to be considered the basic process to
enhance the profitability of the feed. Extrusion process benefits in term of
enhanced nutritional value and efficiency of ingredients and feed, depending upon
many factors like structure and chemical composition of the ingredients, process
ing
conditions and machinery used in processing. Any variation for example change in
temperature, moisture, screw speed, pressure, time along with extruded material
chemical composition and structure can easily influence the nutritional value,
digestibility of feed or feed ingredients and performance of the poultry bird. To
attain maximum results from the extrusion processing techniques all conditioned
should be maintained at optimum levels.
Key words
Extrusion
processing,
Nutritiona
l
value,
Growth
Int.J.Curr.Microbiol.App.Sci
(2015)
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): 48
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49
productivity, energy efficiency and high
quality of the resulting product(
Brenes,
Viveros, Centeno, Arija, & Marzo, 2008
;
Moritz et al., 2005). Extrusion may increase
digestibility of starch by starch
gelatinization,
melting, fragmentation,
destruction of antinutritional factor and
making starch easily accessible to digestive
enzymes
(Abd El-Khalek & Janssens, 2010
;
Dust et al., 2004
;
Lankhorst, Tran,
Havenaar, Hendriks, & van der Poel, 2007
;
Liu et al., 2013
;
Ljokjel, Sorensen,
Storebakken, & Skrede, 2004
;
Murray et al.,
2001)
. Extrusion may alsobe able to increase
digestibilityvalue of proteins, amino acids
and nitrogen (Al-Marzooqi & Wiseman,
2009
;
Cheftel, 1979
;
Sagum & Arcot, 2000)
.
Extrusion process in uences protein
digestibility by denaturation of protein,
modification of side chains of amino acids
and denaturing of antinutritional factor.
Denaturation of protein leads to increased
digestibility
(
Cheftel, 1979
).
It is not always seen that extrusion increase
the digestibility of starch and protein. Some
time it has no effect or may reduce the
protein and starch digestibility of the feed
ingredients or feed (G. H. Chiang, 1983
;
Dahlin & Lorenz, 1993
;
Hurr
ell &
Carpenter, 1981
;
Ljokjel, Harstad, & Skrede,
2000
;
Mahasukhonthachat, Sopade, &
Gidley, 2010
;
Plavnik & Sklan, 1995
;
Saalia
& Phillips, 2011
;
Skrede & Krogdahl,
1985).Extrusion cooking may be defined as
a short time high-temperature process in
wh
ich moistened, starchy and/or
proteiniousfood or food materials are
plasticized and cooked in a tube with the
help of moisture, temperature, pressure and
mechanical shear. Any variation in this
process for example change in temperature,
moisture
(Wood, 19
87
) screw speed(
M.
Bhattacharya & Hanna, 1985
;
B. Y. Chiang
& Johnson, 1977)pressure, time along with
extrud
ed material chemical composition and
structure
(Becker, Hill, & Mitchell, 2001
;
Colonna & Mercier, 1985
;
Lin, Hsieh, &
Huff, 1997) can easily influence the
digestibility of feed or feed ingredients. So,
to achievebetterresults from the extrusion
process optimum conditions should be
maintained.
Gelatinization of starch, structural changes
in protein and amino acid, denaturation of
anti
-nutritional factors along with
sterilization of ingredients are the main
features of extrusion process which leads to
the better digestibility, intake, feed
conversion ratio and production in po
ultry
birds. Many researchers have reported
positive effect of extrusion on the
performance of the
chicken
(Amornthewaphat, Lerdsuwan, &
Attamangkune, 2005
;
Marsman et al., 1997
;
Moritz et al., 2005
;
Nageswara
and Reddy,
2004). They attributed better performance to
improvedgelatinization, intake, digestibility,
removal of anti-nutritional factors and good
quality of extruded feed or ingredients.
However, sometimes extruded
food/ingredients have no effect or have
adverse effect on performance of the
chicken
(Ljubojevi , N. Milo evi , S.
Bjedov, & V. Stana ev, 2011
;
Naber &
Touchbur.Sp, 1969
;
Sloan, Bowen, &
Waldroup
, 1971). These results were
associated to different extrusion condition
and chemical composition of the ingredients
which influence the performance of the
poultry. This review is based on some
question like what is extrusion. Is there any
positive or negative effect on the
ingredients/feed nutritive value due to
extrusion? How poultry bird responds when
fed extruded feed/ingredients?
What is extrusion?
Extrusion process is short time high-
temperature process in which moistened,
Int.J.Curr.Microbiol.App.Sci
(2015)
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): 48
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50
starchy and/or proteinious food or food
materials are plasticized and cooked in a
tube with the help of moisture, temperature,
pressure and mechanical shear. This process
results in molecular transformation and
chemical reactions within the processed feed
or ingredients. This processing technology
has positive impact as compared to other
heat treatment because of mechanical
shearing. These mechanical shearing
treatments break covalent bond in
biopolymers, disrupt complex structure, and
mix thefood/ingredients. (Bjorck, Asp,
Birkhed, & Lundquist, 1984) in their studies
reported that break covalent bond in
biopolymers, disrupt complex structure, and
mixing of food/ingredients by mechanical
shearing treatment facilitate change in the
functional properties of food/ingredients and
or texturize them.Furthermore, the extrusion
process has also positive impact in term of
denaturing of harmful enzymes, inactivation
of anti-nutritional factors (tannin, phytate,
trypsin inhibitor, haemagglutanin) and also
sterilize the final product of
extrusion
(
Bhandari, D'Arcy, & Young, 2001
;
Carvalho & Mitchell, 2000).This extrusion
process is used in many different places and
having different application and extensively
used in food and feed
industry
(Amornthewaphat et al., 2005
;
Eastman, Orthoefer, & Solorio, 2001
;
Liu et
al., 2013). Due to increased application of
the extrusion, physic-chemical, function,
and nutritional effects of extrusion process
are considered to be of high importance. The
destruction of anti-nutritional factors,
reduction of the losses of nutrient along with
increasing digestibility of the starch and
protein are considers the bases of extrusion
process. It has also been reported by
different investigators that extrusion process
have both positive and negative effects on
food or feed ingredients/mixture nutritional
quality under different extruder conditions
(temperature, feed m
oisture,
screw speed
and screw con guration) and raw-
material
characteristics (composition, particle size).
Starch
Starchesare polysaccharides made of basic
unit of glucose which are linked together
and form long chains. Amylose and
amylopectin are the two types of starch
molecule. In most natural starch Amylose
(linear) is average 20-30% of the starch. It is
not true for all kind of starch for example
Waxy corn starch contains only amylopectin
(branched). There are also examples of other
starches which only contain
amylose.Presence of these two kinds within
the grains give them specific properties
during cooking process and leads a major
role in gel formation process. The
contribution of amylose and amylopectin in
gel formation gives viscosity to the cooked
mate
rial.Plant stores energy in the form of
starch like rice wheat corn and other grain.
These grains are the store house of energy
for plants. Rice, wheat and corn are the
major sources of starch in poultry feed. It is
not easy for mono-gastric species includ
ing
poultry to digest the grain starch easily. A lot
of studies indicate that extrusion process
have significant effect on the starch
digestibility in the mono
-
gastric animals.
Factor affecting Gelatinization
Moisture Content
Higher level of moisture in the feed, food or
ingredients of feed/food results in higher
degree of gelatinization when combined
with higher temperature. That is the reason;
increasing moisture content leads to higher
degree of hydrolysis
(
Hakulin, Linko, Linko,
Seiler, & Seibel, 1983). (
Wood
, 1987)
observed in his studies that higher moisture
content (30-50%) leads to efficient
gelatinization. Furthermore, limited amount
Int.J.Curr.Microbiol.App.Sci
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): 48
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51
of water or solvent in the substrate required
higher heat for complete gelatinization(
Sun,
W. Yang, T. Siebenmorgen, A. Stelwagen, &
Cnossen, 2002). At the same time other
researcher
(S. Bhattacharya, Das, & Bose,
1988
;
Lin et al., 1
997
)also reported that
increase water content reduce the
gelatinization of products during the process
of extrusion. (Lund, 1981) indicated that,
usually, water to starch ratio 1.5:1 is
required for complete gelatinization, and
water to starch ratio 0.3:1 may be required
for beginning of gelatinization process.
Amylose to Amylopectin Ratio
Am
ylose and amylopectin quantity within
the cereals grains affect the gelatinization
process. Cereals are more resistant to
gelatinization with high amylose content
during the extrusion processing as compared
to cereals having the moderate to high
content of amylopectin. Starches which are
high in amylopectin are easy to swell as
compare to starch rich in amylose, amylose
containing starch during extrusion loss order
within the granules, followed by its
destruction
(Colonna & Mercier, 1985).
There is also opposite finding about this
study that higher temperature is required for
high and low amylopectin starch barley as
compare mid
-
range barely.
Lipids
In cereals internal lipid have been sho
wn
there effect on starch granules swelling and
gelatinization properties. Increasing and
decreasing the fat content effect the starch
gelatinization in extrudates. (Lin et al.,
1997)reported significantly decreased starch
gelatinization in extrudates when fat content
were increased in the byproduct. In this
study the decreased gelatinization was might
be due to the presence of starch-
lipid
interaction.
(Mira, Persson, & Villwock,
2007) reported star
ch
lipid interactions
decrease starch swelling capacity. Many
other scientists also reported that starch
-
lipid
interaction decrease solubility and granule
disruption
(Bhatnagar & Hanna, 1994b
;
Galloway, Biliaderis, & Stanley, 1989
;
Ghiasi, Varrianomarston, & Hoseney, 1982)
.
The amylo-lipid complex within starch
granules restricts the penetration of the
water
(Becker et al., 2001). (
Hoov
er &
Manuel, 1996) reported Amylose-
lipid
interaction and crystallite reorientation in
normal maize, waxy maize, dullwaxy maize
and amylomaize V starches by applying heat
moisture treatment. Amylose
-lipid formation
depends upon the material starch and li
pid.
Monoglycerides and free fatty acids are
more susceptible to make these kinds of
complexes as compare to triglycerides
(
Bhatnagar & Hanna, 1994a
).
Processing/Screw Speed
Processing time and screw speed of the
extruder have also major effect on the
gelatinization of the extrudate.(
Jain,
D.Mridula, & Neharika, 2013)reported that
screw speed alters the physical
characteristics of the extrudates. (
Basediya,
Pandey, Shrivastava, Khan, & Nema,
2013)
reported
that during extrusion process
speed ofextruder influence the nutritional
quality of the extrudates. Decrease starch
gelatinization has been reported by
researcher
(B. Y. Chiang & Johnson, 1977)
by incr
easing
the speed of screw
during
processing
. T
hey concluded that the reduced
starch gelatinization was due to less cooking
time caused by enhanced screw speed
whichdecreased
retention time of the sample
in the extruder. Changes of screw speed
result
ed in changes of products temperature
and variation in the
temperature
may be able
to
influence the starch gelatinization
.
S
imilar
results have been reported by (Lin et al.,
1997) during study.
They
reported
changes
Int.J.Curr.Microbiol.App.Sci
(2015)
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): 48
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52
in
starch gelatinization caused by variation of
temperature
due to screw
spe
ed.A
s
described
earlier
during
extrusion process
screw speed is also one of the
factorsa
ffect
ing
nutritional value of
substrate
(Basediya et al., 2013). T
he
screw
produce
s
the sh
e
ar force which is also one of
the
reasons
to
change
the nutritional value of
extrudates
(Marsman, Gruppen, &
Vanderpoel, 1993). Normally, shear forces
are varied by changing the screw speed.
However, by changing the screw speed the
residence time is largely affected.
Granule size
Granule size has effecton gelatinization of
starch during extrusion process.Larger the
granule sizes, easier is to gelatinize and the
smaller granule size takes long time to
get
gelatinize
d
.
(Chiotelli & Le Meste, 2002
;
Peng, Gao, Abdel-Aal, Hucl, & Chibbar,
1999)reported that large starch granules
within the endosperm have a higher
gelatinizationcapacity than small granules
and hence
re
ectgreater crystallinity of large
granuleas compare to small starch granules.
The process of extrusion reduces particle
size and changes the crystalline structure of
the starch which makes starch more
available for digestive enzymes (Goelema,
Smits, Vaessen, & Wemmers, 1999
;
Thomas, Huijnen, van Vliet, van Zuilichem,
& van der Poel, 1999
).
Effect of extrusion processing on
digestibility of poultry
Starch structure of cereals is an important
factor for digestion of starch and is therefore
considered as key factor to determine the
quality of starch in feed. Starch digestion is
also affected by other factor like animal
related factors. Animal related factor are
breed, age, sex, feed intake and passage rate
of feed in gastrointestinal tract of the animal.
Hence the starch digestibility of
gastrointestinal tract in poultry depends
upon a lot of factors including amylose and
amylopectin ratio. Extrusion process is also
one of major factors affecting digestibility of
starch by its gelatinization. (Nayak, Berrios,
& Tang, 2014)reported that extrusion
process is involved in the gelatinization
process. Other researchers(Lankhorst et al.,
2007) also reported that the quality of
carbohydrate can be modified by thermo-
mechanical treatment through gelatinization
or shift towards the resistant starch (Dust et
al., 2004). In excess water condition, less
systematic amorphous regions of starch
disrupted
firstly, which allows the water to
join free hydroxyl group of the starch
granules. The effect of moisture on starch
may be due to its new crystallization or
recrystallization or due to perfection
ofstarch granules crystallization regions.
High temperature and moisture extrusion
results in greatergelatinization and
signi
cant rise in
in
-
vitro
starchdigestibility
(Ljokjel et al., 2004
;
Murray et al., 2001
;
Zimonja and Svihus,
2009)
and
in
-
vivo
starch digestibility (
Nalle
et al., 2013
;
Zimonja and Svihus, 2009).
(Nalle et al., 2013) reported enhanced
apparent illeal starch digestibility in their
experiment. The digestibility of the starch
due to extrusion is increased due
to
gelatinization and by making starch more
liable to enzyme degradation.
Glennie
(1987) explained more starch susceptibility
to enzyme degradation after extrusion
process due to increased water solu
bility
indices, reduced amylose content and
molecular weight of starch during the
extrusion process
.
Zimonja
and
Svihus
(2009)
reported
increased starch
susceptibil
ity for enzymatic breakdown in
the higher gelatinization degree of the
starch.
Abd El-
Khalek and
Janssens (2010)
also reported similar finding that extrusion
of corn showed an increase digestibility of
Int.J.Curr.Microbiol.App.Sci
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53
starch because of accessibility of digestive
enzymes to starch. Water or moisture
content is always considered primary part of
the extrusion process. Some studies have
reported that extrusion without water can
als
o improve the digestibility of the raw
starches
(Al-
Marzooqi
and
Wiseman, 2009
;
Liu et al., 2013). Improvement in
di
gestibility of raw starches during extrusion
process without water might be due to
granular disorganization (as evidenced by
X-ray diffraction patterns) and changes in
crystallinity
(Al-
Marzooqi
and
Wiseman,
2009). Improved starch gelatinization and
digestibility has also been reported by (
Liu
et al., 2013
)
in dry extrusion.
Ex
trusion process is not always considered
to increase the digestibilty of the ingridients
(
Davis
and
Arnold, 1995
;
Nalle et al., 2013)
.
Although it is considered more benficial
method to increase the digestibility of the
starch but it is not true in every situation.
Some time it has no effect or negative effect
on the digestibility of the ingridients or feed.
Plavnik
and
Sklan (1995) have found no
differences in starch apparent digestibility of
extruded diet in broiler.
Dahlin
and
Lorenz
(1993) reported lower carbohydrate
digestibility in high tannin sorghum
extruded
at low
-
moistures (15g/kg) and low
-
temperatures (80 100
C).
Mahasukhonthachat et al. (
2010
) reported
starch decreased rate that was due to
increasing extrusion moisture from 250 to
400 g/Kg. For maximum benefits from the
extrusion process, in case of digestibility,
the
extrusion condition should be standardized.
It is necessary to standardize the temperature
and moisture during the extrusion process
because fluctuation in the temperature may
be able to affect t
he gelatinization process of
starch. Retrogradation of starch is also an
important factor in the process of
gelatinization. This process occurs when
gelatinized starch internal molecule re-
associate. Retrogradation process occurs
more quickly in the amylose based starch
while the process of retrogradation is known
to be low in amylopectin based starch and
need more time (
Lii
et al., 2004). It is
generally described that in mono gastric
animal retrograded starch is resistant to
digestion
(
Eerlingen
et al., 1994).
This
process mainly depends upon the
concentration of the water (
Zeleznak
and
Hoseney, 1986). To obtain maximum
benefits from extruded diet/ingredients
water concentration should be maintained at
standard level.
As described earlier extrusion process may
ca
n increases the digestibility of the starch
and proteins. A lot of reasercher have
reported positive effect on digestibility of
protein by extrusion process (
Ahmed
et al.
,
2014
; Al
-
Marzooqi
and
Wiseman, 2009
;
Arija et al., 2006
; Lichovnikova
et al., 2004
;
Marsman et al., 1997
;
Nalle et al., 2013).
It
should be kept in mind boht possibilities of
increasing and decreasing digestibiltiy can
happen after the extrusion process. Th
ese
possiblities mainly depends upon the
processing conditiones, chemical
compostion and other factors. Processing
pattren especailly heat processing of food
in
uences protein digestibility
bydenaturation of protein which increase
protein digestibility. Heat processing
alsomodifiyside chains of amino acids
which delay the action of digestive enzymes.
Al-
Marzooqi
and
Wiseman (2009)
reported
infuenced amino acid digestibility in
growing
poultry birds fed ingredients
extruded at high processing temperatures.
Signi
cantly higher apparent ileal crude
protein (CP) digestibili
ty
. Marsman et al.
(1997) was reported in broiler fed extruded
soybean meal. Improved ileal digestibility of
CP and amino acids in chicken has also been
reported by Arija et al. (2006) when broiler
chicken were fed diet containing extruded
Int.J.Curr.Microbiol.App.Sci
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54
kidney bean. Extrued diets in laying hen also
increased total tract apparent digestibility
(TTAD) of essential amino acids an
d
nitrogen retention (Lichovnikova et al.,
2004). Ahmed et al. (2014) r
eported
increased
apparent ileal digestibility of CP
and some of AA such as Asp, Glu, Ser, Thr
and Trp when fed extruded canola meal to
the chicken. Nalle et al. (2013)
reported
reduced trypsin inhibitor activity of peas
following extrusion process. Similarly,
Mariscal
-
Landin
et al. (2002) reported that
reducedtrypsin inhibitor actvityin rawand
extruded Friléne peas which were supposed
to increase protein and amino
aciddigestibilities.Similar results have been
reported by other workers (
Hancock
et al.,
1992
;
Hancock
and
Bramel
-Cox, 1991).
As
already discussed that heat treatment can
also increase the digestibility of the amino
acid. This theory is supported by
Fernandezfigares
et al. (1995)
experiments.
They reoported increased digestibility of
amino acid in growing broiler
fed
heat
treated (autoclaving) vetch and bitter vetch
meals. Fapojuwo
et al. (1987) also reported
59% increased digestibility (0.449 versus
0.714) when dry extrusion temperature of
sorghum increased from 50 to 200
C.
Extrusion process is not always considered
to have beneficial effect on the digestibilty
of the ingridients (
Davis
and
Arnold, 1995).
This process may have no or negative effect
on the bioavailability and digestibility of the
protein, amino acid and nitrogen of the
ingridients/feeds. The variation in the
digestibility may be attributed due to a lot of
factor like fluctuation in the processing
condtioned, chemical composition of the
indgirdients and machinary used. Nalle et al.
(2013) reported that extrusion had no effect
on apparent ileal protein digestibility.
Heat processing have negative effect of
the
bioavailability of the amino acids in feed
stuff
(
Parsons
et
al.,
1992
). Over heating of
feed stuff can decrease protein solubility and
may also can destroy certain amino acids
(
Araba
and
Dale, 1990). Negative effect of
high extrusion temprature has also been
reported by
Vande
rpoel
et al. (1992). These
effects can reduce the digestibility of protein
and amino acid.
Skrede
and Krogdahl
(1985) reported reduced total tract
digestibility of all amino acids due to heat
treatment of soybean meal by autoclaving at
135°C for 30 minutes. Similar results on the
protein and amino acid digestibility results
has b
een repoted by
Ljokjel et al.
(
2000
)
and
Ljokjel et al. (2004). Similar findings were
also observed for amino acid digestibility
with increased heat treatment, mainly for
lysine
(Martinez Amezcue
and
Pars
ons,
2007
). Some time processing techniques
have no effect on the digestibility of the
protein.
Nalle et al. (2013) reported extrusion
process of Peas (Pisum sativum L.) did not
change apparent ileal protein digestibilty.
Saalia
and
Phillips
(
2011
) reported
similar
results about
in
-
vitro
protein digestibility
and fluorodinitrobenzene (FDNB)-available
lysine between extruded and non-
extruded
peanut meal. One of the most important
amino acid is lysine, which is mostly
condsidered firs
t limiting amino acid in creal
based animal feed, is very susceptible to
heat treatment and can easily react with free
sugar cause Milard reaction. Due to this
milard reaction the availability of the lysine
reduced so the digestibilty of the feed is
reduced.
Effect of extrusion processing on
performance of poultry
Extruder conditions along with compositon
of ingridients and feed may influences starch
gelatinisation at vairous level which may
cause differences in growth performance of
Int.J.Curr.Microbiol.App.Sci
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55
the poultry. Different studies described
different effect of extrusion on the
perfornamce of the poultry
(Amornthewaphat et al., 2005
;
Ljubojevi et
al., 2011
;
Nageswara et al., 2004
;
Sloan et
al., 1971). Extrusion of corn meal has
signif
icantly affected the improvement of
production performance of broiler chickens.
Moritz et al. (2005) observed that extrusion
process of corn led to an increase in bo
dy
weight of broiler chickens, aged 0 to 3
weeks. Furthermore, Marsman et al. (1997)
reported improved growth performance of
the broilers fed extruded SBM. Conditioning
time can change the degree of geletinization
of starch. So,degree of geletinization can
affect the growth rate and body weight of
the poultry. Abd El-
Khalek
and
Janssens
(2010) reported different degree of
geletiniztion affect the body weight and
growth rate in pigon.
Extrusion process may also have no effect
on the performance of the poultry
(Nageswara et al., 2004)
.
Sloan et al. (1971)
reported
that extrusion have no effect on
weight gain and feed effeciency ratio in
broilers.
Similar observations were made by
Naber
and
Touchbur.Sp (1969).
Nageswara
et al. (2004) also reportedno benefical effect
on performance of layer by using different
processing techniques on maize-soy or
maize soy-palm kernal diets including
extrusion cooking or expander extrusion
except extrusion processing of the maize soy
diet which only improved feed utilisation
ef
ciency. Similarly, Ljubojevi et al. (
2011
)
reported
similar production for
both
extruded and control feed and concluded
there was no expectation that the extrusion
process had major po
sitive effects.
It is considered that extrusion have positive
effect on the performance of the chicken but
there are also some studies which reported
negative effect of extrusion on the
performance of chicken. Amornthewaphat et
al.
(2005) observed that extruded crushed
corn has a negative effect on performance of
broilers. Similar results on growth
performance of broilers have also been
reported by Zhuge et al. (1990) when fed
diet having sorghum that was wet-
extruded
130/135
C prior to incorporation into broiler
diets.
Moisture content of diets may also in uence
feed intake
(
Moritz et al., 2001
)
and thus can
influence the digestibility and performance
of the poultry bird. One explanation for the
variation in results may that these
differences are due to different types of
extruders (wet or dry, with one or two
extractors) and different condition during
the extrusion process, such as temperature,
humidity, pressure, etc. (Hongtrakul et al.,
1998). Table Re
ferences
(
Alonso
et al.,
2000
;
Camire
et al.
, 1990
).
On the basis
of
the reviw, although extruion
technique seems to have more benfits on
nutritient digestibility and performance in
poutlry but extrusion porcess effect on
nutrient digestibility and performance of
poultry is in-consistent. The unequivocal
performance of poultry and nutrient
digestibility was mainly due to variationsin
processing techniques and extrusion
conditions. To obtain maximun nutrient
digestibility and performance of the poultry
processing techniques and extrusion
conditions should be maintained at standard
levels.
Int.J.Curr.Microbiol.App.Sci
(2015)
4(
4
): 48
-61
56
Geletinization Digestibility of Starch Digestibility
Protein,Nitrogen, amino
acids
Performance
Sloan et al., 1971 Extrusion X X X Performance
Cheftel, 1979 Extrusion X X Protein X
Hurrell and Carpenter, 1981 Extrusion X X Amino Acid X
Chiang, 1983
Extrusion X X Amino Acid X
Skrede and Krogdahl, 1985 Extrusion X X Protein, Amino Acid X
Fapojuwo et al., 1987 Extrusion X X Protein X
Bhattacharya et al., 1988 Extrusion Geletinization X X X
Zhuge e t al., 1990 Extrusion X X X Performance
Camire et al., 1990 Extrusion X Digestibility X X
Hancock and Bramel-Cox, 1991 Extrusion X X Nitrogen X
Hancock et al.,1992 Extrusion X X Nitrogen X
Dahlin and Lorenz, 1993 Extrusion X Digestibility X X
Plavnik and Sklan, 1995
Extrusion X Digestibility X X
Marsman et al., 1997 Extrusion X X CP,Amino Acid Performance
Ljokjel et al., 2000 Extrusion X X Protein, Amino Acid X
Alonso et al., 2000 Extrusion X Digestibility X X
Murray et al., 2001 Extrusion Geletinization X X X
Sun et al., 2002 Extrusion Geletinization X X X
Lichovnikova et al., 2004 Extrusion X X Amino Acid X
Dust et al., 2004 Extrus ion Geletinization X X X
Nageswara et al., 2004 Extrusion X X X Performance
Ljokjel et al., 2004 Extrusion Geletinization X X X
Amornthewaphat et al., 2005 Extrusion X X X Performance
Moritz et al., 2005 Extrusion X X X Performance
Milo evi et al., 2006 Extrusion X X X Performance
Arija et al., 2006 Extrusion X X CP,Amino Acid X
Martinez Amezcua and Parsons, 2007 Extrusion X X Amino Acid X
Zimonja and Svihus, 2009 Extrus ion Geletinization Digestibility X X
Marzooq and Wiseman 2009 Extrusion Geletinization X X X
Mahasukhonthachat et al., 2010 Extrusion X Digestibility X X
El-Khalek and Jamssens, 2010 Extrusion X Digestibility X X
Ljubojevi et al., 2011 Extrusion X X X Performance
Liu et al., 2013 Extrusion X Digestibility X X
Represents Increasing trend
Represents no effect
Process
Author
Reasults
Extrusion effect on Digestibility and Performance in Poultry: SUMMARY
Represents decreasing trend
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