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Effect of Crumble-Pellet and Mash Diets with Different Levels of Dietary Protein and Energy on the Performance of Broilers at the End of the Third Week



This experiment was conducted to investigate the effect of the form of diets with different levels of protein and energy on broilers performance at the end of the third week. A total of 2800 male broiler chicks were fed with two forms of diet (mash and crumble-pellet), two levels of protein (23% and 21% CP), and two levels of energy (3200 and 3000 Kcal/Kg ME) from 1 to 21 days of age. The bodyweight (BW) and Feed conversion rate (FCR) were affected by the form of diet with the crumble-pellet form being better (P < .001). The diet with high protein significantly increased BW and decreased FCR (P < .001). The different levels of energy did not affect FCR and BW in crumble-pellet diet but should a significant effect on them in mash diet (P < .05). There were no significant interactions for any of the parameters tested except for interactions between energy and feed form. BW and FCR were improved by energy when diets were fed in the mash form (unlike the crumble-pellet form) at all ages. It is concluded that feeding crumble-pellets from 1 to 21 days of age improved BW and FCR and that an increase in the protein (unlike energy) content of the diet increased the performance of the chickens at the end of the third week.
SAGE-Hindawi Access to Research
Veterinary Medicine International
Volume 2010, Article ID 328123, 5pages
Research Article
Effect of Crumble-Pellet and Mash Diets with Different Levels of
Dietary Protein and Energy on the Performance of Broilers at the
End of the Third Week
S. Jafarnejad,1M. Farkhoy,2M. Sadegh,1and A. R. Bahonar3
1Faculty of Veterinary Medicine, University of Tehran, P.O. Box 14155-6453, Tehran, Iran
2Department of Animal and Poultry, Health and Nutrition, Faculty of Veterinary Medicine, University of Tehran, P.O. Box 14155-6453,
Tehran, Iran
3Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, P.O. Box 14155-6453, Tehran, Iran
Correspondence should be addressed to S. Jafarnejad,
Received 4 July 2010; Revised 9 November 2010; Accepted 27 December 2010
Academic Editor: Sagar M. Goyal
Copyright © 2010 S. Jafarnejad et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
This experiment was conducted to investigate the eect of the form of diets with dierent levels of protein and energy on broilers
performance at the end of the third week. A total of 2800 male broiler chicks were fed with two forms of diet (mash and crumble-
pellet), two levels of protein (23% and 21% CP), and two levels of energy (3200 and 3000 Kcal/Kg ME) from 1 to 21 days of age.
The bodyweight (BW) and Feed conversion rate (FCR) were aected by the form of diet with the crumble-pellet form being better
(P<.001). The diet with high protein significantly increased BW and decreased FCR (P<.001). The dierent levels of energy
did not aect FCR and BW in crumble-pellet diet but should a significant eectontheminmashdiet(P<.05). There were no
significant interactions for any of the parameters tested except for interactions between energy and feed form. BW and FCR were
improved by energy when diets were fed in the mash form (unlike the crumble-pellet form) at all ages. It is concluded that feeding
crumble-pellets from 1 to 21 days of age improved BW and FCR and that an increase in the protein (unlike energy) content of the
diet increased the performance of the chickens at the end of the third week.
1. Introduction
Successful broiler development is dependent on optimal feed
intake throughout the growing period. Optimal feed intake
is dependent on a number of factors such as environmental
temperature, and diet nutrient density, and physical feed
quality is considered to have a very significant impact on
broiler growth. Energy and protein are very important
nutrients for broilers like other living creatures. Energy is
required for body functioning and protein is an essential
constituent of all tissues of animal body. Protein having
major eect on growth performance of the bird is the most
expensive nutrient in broiler diets [1]. It is a widely accepted
principle in poultry nutrition that dietary energy and the
essential nutrients must be considered as an entity. To ensure
maximum utilization of energy, protein, and every nutrient
of the diet, a right proportion of these nutrients are necessary
for optimum growth of the birds and for minimization of the
surplus use of vital dietary component, and because the first
few days after hatch now represent a greater percentage of a
broiler’s lifespan than any time in history, it is critical that the
bird be given every opportunity to get oto a good start.
The physical form of feed (mash and pellet) is a crucial
factor in meat yield of broiler. Mash is a form of a complete
feed that is finely ground and mixed so that birds cannot
easily separate out ingredients; each mouthful provides a
well-balanced diet. Mash diet gives greater unification of
growth and less death loss and is more economical. However,
ground feed is not so palatable and does not retain its
nutritive value so well as ungrounded feed [2]. Pellet system
of feeding is really a modification of the mash system. It
consists of mechanically pressing the mash into hard dry
pellets or “artificial grains”. It is generally accepted that,
compared to mash, the feeding of pellets improves broiler
SAGE-Hindawi Access to Research
Veterinary Medicine International
Volume 2010, Article ID 328123, 5 pages
2Veterinary Medicine International
Tab le 1: Ingredient composition and nutrient content of experiment diet (as fed basis).
Crumble-pellet diets Mash diets
Ingredients(g/100gr) 12345678
Yellow corn 48.4 51 54.8 57.2 48.4 51 54.8 57.2
Soybean meal 37.9 40.5 32.4 35.2 37.9 40.5 32.4 35.2
Oil 7.15 4 6.1 3 7.15 4 6.1 3
Monocalcium phosphate 1.45 1.4 1.5 1.45 1.45 1.4 1.5 1.45
Limestone 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7
Salt 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4
Dl-methionine 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3
Lysine 0.21 0.15 0.27 0.23 0.21 0.15 0.27 0.23
Vit. & min. premix10.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
Wheatgluten 20202020
Calculated composition
Crudeprotein(%) 2323212123232121
ME (kcal/kg) 3200 3000 3200 3000 3200 3000 3200 3000
Calcium(%) 11111111
Av. phosphorus (%) 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45
Sodium (%) 0.17 0.17 0.17 0.17 0.17 0.17 0.17 0.17
Methionine (%) 0.64 0.64 0.62 0.62 0.64 0.64 0.62 0.62
L-Lysine (%) 1.35 1.35 1.25 1.25 1.35 1.35 1.25 1.25
Methionine + cystine (%) 1 1 0.95 0.95 1 1 0.95 0.95
1Each kg of premix provided vitamin A, 10000 IU; vitamin D3, 2500 IU; vitamin K, 2.4 mg; vitamin E, 44 IU; biotin, 0.1mg; folic acid, 2.0 mg; niacin, 25mg;
calcium pentothenate, 14.32mg; pyridoxine, 3.10 mg; riboflavin, 5 mg; thiamin, 1.2 mg; vitaminB12, 10.5 µg; Fe, 85 mg; Mn, 125 mg; Cu, 7.8 mg; Se, 0.09 mg;
Zn, 60 mg; chol ine chloride, 5 .5 mg.
growth rate with an increased feed intake [36]. Reasons
for the enhanced performance may be due to increased
digestibility, decreased ingredient segregation, reduction of
energy during prehension, and increased palatability [7], but
feeding pelleted rations is not enough to ensure enhanced
performance of poultry. The quality of pellets must be taken
into account also [8].
Crumble also is a type of feed prepared at the mill by
pelleting of the mixed ingredients and then crushing the
pellet to a consistency coarser than mash. Recently this form
of feed has become popular in broiler production due to its
convenience of feeding. Choi et al. [4] reported that chicks
fed the crumbled starter diet consumed more feed.
The aim of this study was to investigate the eects of
dierent levels of energy, protein and dierent feed forms
(mash and crumble-pellet), and interactions between them
on the performance of broilers in starter period upon the
broilers performance.
2. Materials and Methods
A total of 2800 commercial male broilers (Ross 308) were
used in a completely randomized design with eight treat-
ments and seven replications. One-day-old broilers (average
initial bodyweight of 45 g) were allocated to dietary treat-
ments. There were 50 birds per replicate, and the stocking
density was 17 birds/m2. Room temperature was maintained
at 33C during the first week, and it was decreased 3Ceach
week till it reached 27C at the end of the third week. All
diets were corn-soybean based. Feed and fresh water were
supplied ad libitum during the experiment. A 24-hour light
was made available to the chicks throughout the experiment.
The experiment was used in a factorial arrangement 2 ×
2×2 with two forms of diet (mash, crumble and pellet)
(crumble and pellet form of diet used, respectively, in the first
10 days and 10–21 days old), two levels of protein (23% and
21% CP), and two levels of energy (3200 and 3000 Kcal/Kg
ME). The ingredient composition and analysis of the basal
diets are shown in Tab l e 1. Feed intake and weight gain were
recorded at the end of first, second, and third week, and feed
conversion ratio (FCR) was calculated. The experimental
design was analyzed statistically using ANOVA technique.
The GLM is used to summarize data in some parameters that
are pertinent to the experiment.
3. Results and Discussion
Data on weight gain and FCR at the end of first, second,
and third week are presented in Ta bl e 2 . The weight gain was
significantly greater in broilers fed crumble-pellet diets than
mash diets when assessed over trial period (P<.001). T1
(crumble-pellet form with 3200 Kcal/Kg and 23% protein)
had the highest weight gain (951 g) and the best FCR (1.31).
The results were in accordance with those of van Biljon [9]
who reported that chickens on the crumble-pellet dietary
regimen were significantly heavier at 42d when compared
with birds fed either all-mash or ground crumble-pellet
regimen. Jahan et al. [2] reported that the highest body
Veterinary Medicine International 3
Tab le 2: Weight gain and feed conversion ratio (FCR) of broiler chickens fed on mash and crumble-pellet as aected by va rious metabolizable
energy (ME) and crude protein (CP) levels of the dietsat the end of the third week (mean + SE).
Treatments Protein
form Weight gain (g) FCR (g/g)
1st wk 2nd wk 3rd wk 1st wk 2nd wk 3rd wk
1 23 3200 A 177ab ±1.7 486a±4.8 951a±5.3 .84c±0.004 1.13d±0.009 1.31e±0.013
2 21 3200 A 172b±2.1 464b±4.8 905b±6.2 .86c±0.003 1.15d±0.009 1.35d±0.009
3 23 3000 A 179a±3.1 488a±6.8 936a±10.5 .85c±0.005 1.14d±0.011 1.30e±0.012
4 21 3000 A 177ab ±2.2 475ab ±4.2 913b±6.4 .88c±0.018 1.18c±0.004 1.37cd ±0.007
5 23 3200 B 162c±1.8 438c±4.6 842c±4.4 .87c±0.024 1.18c±0.016 1.36d±0.014
6 21 3200 B 156de ±1.6 422d±3.1 818d±8.5 .89bc ±0.020 1.21c±0.011 1.39c±0.004
7 23 3000 B 158cd ±1.8 420d±3.3 798d±6.4 .94ab ±0.032 1.24b±0.013 1.43b±0.013
8 21 3000 B 151e±1.6 401e±2.4 757e±8.3 .95a±0.007 1.28a±0.005 1.49a±0.008
Pvalue .000 .000 .000 .000 .000 .000
a-b-c-d Means with lacking common superscripts dier significantly.
Mean of 7 replicates having 50 birds in each replicate.
∗∗A; crumble-pellet diet, B; mash diet.
weight gain was observed in the crumble group throughout
the experiment period, but these data were statistically
similar with pellet group from 5 to 8 weeks of age. Allerd
et al. [10] also reported that chicks grew faster when fed
as pellets or crumbles than when the same diets were fed
as mash. In accordance with other authors results [36,11]
the feeding of pellets, compared to mash, improved broiler
growth rate, which was associated with an increased feed
intake and improved feed conversion eciency. Also, Agah
and Norollahi [12] reported that the usage of mash diet in the
first ten days and pellet diet in other growing periods could
be having the best FCR and the highest weight gain which is
in agreement with the result of this study.
Fairfield [13] noticed that pelleting of feed also provides
the benefits of increasing the bulk density of feed, improving
feed flow ability and providing opportunities to reduce feed
formula costs through the use of alternative feed ingredients.
Maximum weight gain was observed in birds fed on diet
containing 23% CP on both crumble-pellet and mash diets
in all weeks (P<.001). Birds fed dietary energy levels of
3200 Kcal ME/kg gained significantly more weight than birds
fed 3000 Kcal ME/kg in the mash diets at second (P<.05)
and third (P<.001) weeks but no dierence in BW was
noted for birds fed the pellet diets with the dierent levels
of metabolizable energy in all weeks.
Metabolizable energy had a significant interaction with
feed form for all of the performance parameters studied.
There were interactions between metabolizable energy and
feed form on BW and FCR at all ages examined. Both main
eect and interactive data are shown in Tab l e 3.Bodyweight
was not aected by metabolizable energy when diets were fed
in pellet-crumble form. In contrast, BW decreased and also
FCR increased with reduced energy when diets were in mash
form (Ta b le 3 ).
Conflicting results on the interaction between feed forms
and energy have been reported. Whereas some trials have
showed significant interactions [14,15], others did not [16].
Scott [17] has reported a decrease in growth rate with
decreasing nutrient density and metabolizable energy when
diets were fed in mash form which is similar to the findings of
this research. This relationship was likely a reflection of the
reduced ability of birds to eat the bulkier, and possibly less
palatable, low-density mash ration. The interaction between
nutrient density and feed form on feed intake supports this
CP diets gained more weights as compared to those fed
high ME and low CP diets. These findings are contrary to
those reported by Holsheimer and Veerkamp [18], claiming
that the normal-CP diets gave significantly higher gains
than the high-CP diets at 6, 7, and 8 weeks of age. The
results were also in accordance with those of Onwudike [19]
who reported an increased daily weight gain with 2800 Kcal
ME/kg and dietary protein of 22% (in compare to 20%) in
broiler chickens. The findings of this study were in close
agreement with those of Leeson et al. [20] who found that
high-energy and low-protein diets (3000 Kcal ME/kg and
20% CP) depressed the growth of broilers. They also reported
significantly higher body weight gains with 24 and 22%
CP compared to 20%. However, Leeson et al. [21]reported
that body weight gain and growth rate were unaected by
the level of the energy in diet of broiler chicks that is in
agreement with the result of this study. Han et al. [22]
observed no dierence in body weight gain in low-protein
diets for broilers when being fortified the low-CP diets with
essential amino acids. So, it seems that growth depression
due to low-protein diets may be due to low-amino-acid
profile of such diets. In this trial, FCR was aected by the
form of diet with the pellet form being better in all weeks
On the crumble-pellet and mash diets, it was noted that
birds fed on diets containing 23% CP had lower FCR than
the birds fed on diet containing 21% CP, specially at the 2nd
and 3rd week (P<.001). A similar response to dietary energy
was observed for FCR in the mash diets at the 1st week (P<
.01) and at the 2nd and 3rd weeks (P<.001), but the eect
4Veterinary Medicine International
Tab le 3: The eect of energy, protein, and feed form and their interactions on the performance of broilers fed mash and crumble-pellet diet
BW(1st wk) NS NS ∗∗ NS ∗∗∗ ∗∗∗ NS
BW(2nd wk) NS NS ∗∗∗ NS ∗∗∗ ∗∗∗
BW(3rd wk) NS NS ∗∗∗ NS ∗∗∗ ∗∗∗ ∗∗∗
FCR(1st wk) NS NS NS ∗∗∗ NS ∗∗
FCR(2nd wk) NS NS ∗∗ NS ∗∗∗ ∗∗∗ ∗∗∗
FCR(3rd wk) NS NS ∗∗∗ NS ∗∗∗ ∗∗∗ ∗∗∗
NS =nonsignificant; P<.05; ∗∗P<.01; ∗∗∗ P<.001.
P: counteraction between energy and protein; EF: interaction between energy and feed form; PF: interaction between
protein and feed form; EPF: interaction between energy, protein, and feed form.
of dierent levels of energy on FCR in the pellet diets was
insignificant except for the 2nd week (Tables 2and 3).
The results of this study are in agreement with those of
Onwudike [19]andTemimetal.[23] who reported that feed
eciency was improved with increasing dietary CP levels
for broiler chicks. The results were also in accordance with
those of Jackson et al. [24] who noted that feed eciency
increased with increasing levels of dietary protein or energy.
The findings of this study are supported by Leeson et al.
[20] who reported improved feed eciency with 22 and 24%
CP and 3000 Kcal ME/kg as compared with diets with 20%
CP and 2600 Kcal ME/kg. Ferguson et al. [25]reportedan
increase in FCR when CP was reduced from 21.5 to 19.6%
in a six-week broiler growth trial. Similarly, Si et al. [26]
reported a significant eect of dietary CP on FCR. Nawaz
et al. [27] also reported that low-ME and high-CP diets
promised optimum performance for broiler chicks at both
starter and finisher phases which is in agreement with the
result of this study.
It is concluded that feeding crumble-pellets from 1 to 21
days of age improved BW and FCR and that an increase in the
protein (unlike energy) content of the diet increased pellet
performance at the end of the third week. In conclusion, it
is obvious that feeding crumble-pellets from 1 to 21 days
of age improves BW and FCR and that an increase in the
protein (unlike energy) content of the diet increases chickens
performance at the end of the third week.
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... The results of this experiment showed that feed form improved growth rate of turkeys. The results were supported by Nir et al., (1994), Yalda and Forbes (1995), Greenwood et al., (2004), Amornthewaphat et al. (2005), Jahan et al., (2006), Salari et al., (2006), Forbes et al. (2007), Mirghelenj and Golian (2009), Yaghoubfar et al. (2009), Jafarnejad et al., (2010, Hassan and El-Sheikh (2010), Chewning et al., (2012) and Farghly (2012). Feed form (pellets) improves the growth rate due to enhanced protein efficiency (Engberg et al., 2002;Greenwood et al., 2004;Aderibigbe et al., 2013). ...
... Pellets have been shown to improve feed conversion by up to four points, possibly due to an increased palatability, reduced ingredient segregation and decreased energy used during feed consumption. The results in the improvement of feed conversion by pelleted feed are in agreement with the findings ofAmornthewaphat et al., (2005),Jahan et al., (2006),Salari et al., (2006), Cutlip, et al., (2008,Mirghelenj and Golian (2009), Yaghoubfar et al., (2009), Hassan and El-Sheikh (2010,Jafarnejad et al., (2010),Awojobi et al., (2011), Beg et al., (2011) and Farghly (2012). However, Canan et al., (2005 and ...
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... Pelleting of feed reduces wastage and increases feed intake by birds (Abdollahi et al., 2013). Processing of the crumble diet involves pelleting the ingredients before crushing them to a consistency coarser than the mash (Jafarnejad et al., 2010) whereas the mash is the finely ground form so that the birds cannot easily separate out the ingredients. However, Sena et al. (2013) noted faster growth among birds reared on pellets. ...
The cost of chicken production in developing countries is 300% higher than in developed nations. Overreliance on the key protein feed ingredients especially soybean and fishmeal (SFM) that are characterized by rising food-feed competition and supply chain impediments exacerbate the situation. The use of insect protein as a sustainable alternative protein source has attracted global attention recently. However, there is a dearth of empirical insights on farmers’ preferences for commercial insect-based feed for chicken production in Sub-Saharan Africa. This study evaluated farmers’ willingness to pay for attributes of insect-based commercial chicken feed in Kenya using a choice experiment based on a survey of 314 predominantly chicken farmers. Results show that the farmers are willing to pay premium prices ranging between US$ 0.35 and US$ 3.45 for insect-based feed in the form of either pellets or mash, feed explicitly labelled as containing insects, insect protein feed mixed with SFM and dark-colored feed. These findings provide evidence for multi-stakeholder collaborations to facilitate the creation of an inclusive insect-based feed regulatory framework for sustainable feed and chicken production.
... Nutrient digestibility, feed consumption, and palatability of pelleted feeds can be modified by pelleting, due to changes in the chemical composition of feed, such as starch gelatinization and protein hydrolysis (Behnke et al., 1994;Massuquetto et al., 2019). Animals that are fed with pelleted feed tend to exhibit better performance compared with animals fed with mash feed (Jafarnejad et al., 2011;Jahan et al., 2006). In addition, the pelleting process can improve the physical characteristics of feed when compared with mash feed. ...
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Pelleted feeds are widely used in monogastric animal production systems because they not only improve animal performance (increasing digestibility and feed consumption) but are convenient to store and handle. However, pellet quality can be affected by many factors. While previous studies have reported the effect of a single or several factors on pellet quality, no studies have investigated how pellet quality can be affected by the large number of factors that vary during feed manufacturing. Therefore, the current study reports using machine learning regression models to predict pellet quality using commercial feed mill data. A dataset consisting of 2,471 observations describing the pellet manufacturing process, the feed formulation, and environmental conditions (e.g. outdoor temperature were collected from two feed mill lines for 8 months. Sixteen features (13 continuous, 3 categorical) were used for building the regression models, and the output was the pellet durability index (PDI) of the pelleted feeds. Twelve regression algorithms including Linear Regression (LR), Least Absolute Shrinkage and Selection Operator (LASSO) regression, Ridge Regression (RR), Support Vector Regression (SVR), Linear Support Vector Regression (LSVR), Random Forest (RF), Decision Tree (DT), Gradient Boosting Regression (GBR), Adaptive Boosting Regression (ABR), Multi-Layer Perceptron (MLP) neural network, K-Nearest Neighbor (KNN), and Stacking Regression (SR) were examined in this study. Feature importance analysis using permutation importance was performed to identify what features were most relevant for each model. Average outdoor temperature, bakery byproduct and wheat inclusion levels, as well as production line, all had high permutation importance values while the fat added into the mixer (with controls at the mill already in place to limit it) was less important than most features. The cleaned dataset was preprocessed and then split into a training (80% of total samples, n = 1,147) and a testing (20% of total samples, n = 287) set. A 5-fold cross-validation process was applied and learning curves were used to verify the presence of overfitting for each algorithm before and after tuning the hyperparameters on the training set. The models that exhibited overfitting were excluded from the final results and only models with tuned hyperparameters were evaluated on the testing set. The SVR algorithm was selected as the best overall model for predicting PDI, as it had the lowest mean absolute and mean squared prediction errors (MAE = 3.280, MSPE = 16.192), and the second highest concordance correlation coefficient (CCC = 0.636). In conclusion, this study shows that feed mill features describing manufacturing parameters, feed formulation, and environmental data can be successfully used to build machine learning regression models for pellet quality prediction.
... Several previous studies on bulk density compared the pellet and mash forms in poultry diets. It was found that the pellet form can increase the bulk density of the feed and that the mash form could improve feed intake, growth, and feed efficiency (Jafarnejad et al. 2010;Chehraghi et al. 2012;Zohair et al. 2012). The second factor is the effect of fiber. ...
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The increasing worldwide production of citric acid by the fermentation of substrates for use as a flavoring and a preservative in foods has resulted in the generation of large amounts of waste and by-products from fermented. There is a challenge to reduce the waste from these products by using them as animal feed. An experiment was conducted to study the utilization of citric acid by-products (CABP) as a feed ingredient in Japanese quail diets. A total of 560 1-day-old quail chicks were randomly distributed into five groups, with CABP included at 0, 3, 6, 9, and 12% of the diets. Each treatment had four replicate pens of 28 birds per pen throughout the 42-day trial period. CABP inclusion at 9 or 12% of the diet, respectively, resulted in a decrease in feed intake of 5.90 and 9.52%, body weight of 5.67 and 9.16%, and body weight gain of 5.44 and 9.97%, compared with the control diet (p < 0.05). Carcass traits and relative organ weights were not significantly different among the treatments (p > 0.05). The 12% CABP group showed a decrease in the digestibility of crude protein and apparent metabolizable energy, but there was an increase in the amount of crude fiber compared with the control diet (p < 0.05). The utilization of CABP in diets can reduce feed costs leading to increased investment returns. In conclusion, CABP can be included at up to 6% of quail diets without significant effects on growth performance or nutrient digestibility.
... Houshmand et al. (2012) observed better growth performance of broiler chickens fed diets containing 23.4% and 20.2% CP for starter and finisher phases, respectively, than in birds fed diets with 15% less protein. Jafarnejad et al. (2010) reported improved productive performance in broilers (1 to 21 days) fed higher dietary protein levels (23% vs. 21% CP). In starter broiler chickens, the optimum dietary CP level has been established at Efecto de la concentración de proteína en la dieta sobre rendimiento productivo, características de la canal y composición química de carne de pollos de engorda en el trópico seco Nº 25, Vol. 12 (2), 2020. ...
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Introducción: Las dietas actuales de pollos de engorda, tienden a incrementar los niveles de proteína para obtener variables productivas altas que son logradas en forma conjunta con mejoras genéticas, de manejo, sanitarias, entre otras. Sin embargo, el incremento en los niveles de proteína en la dieta no siempre acompaña el incremento en eficiencia productiva de los pollos de engorda debido a múltiples factores que intervienen en el sistema de producción. El objetivo de esta investigación fue evaluar el efecto de niveles crecientes de proteína cruda (PC) en las dietas sobre el comportamiento productivo, las características de la canal y la composición química de la carne de pechuga y muslo de pollos de engorde en el trópico seco. Método: El estudio incluyó 200 pollos de engorde Ross de 1 día de edad. Las dietas de tratamientos (T) para las fases de inicio y finalizado tuvieron concentración de proteína cruda (PC; %) de: 21 y 18.1 (T1); 21.4 y 18.5 (T2); 21.8 y 18.9 (T3); 22.2 y 19.3 (T4), respectivamente. Dentro de cada una de las fases de alimentación, las cuatro dietas de tratamiento fueron formuladas con niveles similares de energía metabolizable aparente. En un diseño completamente aleatorio, las aves fueron asignadas a los cuatro tratamientos con cinco réplicas (corrales de piso) de 10 aves cada una. El ensayo se dividió en dos fases (inicio y finalizado) de 21 días cada una (42 días en total). Resultados: La concentración de proteínas no tuvo ningún efecto (P > 0.05) en el aumento de peso, mientras que el consumo de alimento fue mayor en T1 (P < 0.05) que en T2 y T3. La conversión alimenticia fue mejor en T2 y T4 (P < 0.05) que en T1. No hubo influencia del tratamiento en el peso o en los cortes de la canal (P > 0.05). El rendimiento de la canal fue mayor (P < 0.05) en T1 que en T3. La materia seca y el extracto etéreo de la carne de la pechuga y el muslo fueron similares (P > 0.05) entre los tratamientos. La proteína cruda de la pechuga fue mayor (P < 0.05) en T2 que en T3. La menor (P < 0.05) concentración de PC en la carne de muslo fue en T3. Discusión o Conclusión: Estos resultados indican que en la zona subtropical del noreste de México los aumentos de PC sobre los valores de T2 (21.4% y 18.5% PC en dietas de inicio y finalizado, respectivamente) no mejoraron el rendimiento productivo, las características de la canal o la composición química de la carne de pollos de engorde.
... However, the magnitude of pelleting benefits, and therefore its cost-effectiveness, seems to vary depending, besides other factors, on the dietary ND (Leeson et al., 1999;Lecznieski et al., 2001;Lemme et al., 2006;Brickett et al., 2007;Jafarnejad et al., 2010;Abdollahi et al., 2018b). In a recent 21-day study with broilers fed maize-based diets, Abdollahi et al. (2018b), reported that pelleting improved weight gain (WG) by 33.9 % (249 g/bird) in very low (11.71 ...
The influence of nutrient density (ND) and feed form (FF) on the performance, coefficient of apparent ileal digestibility (CAID) of nitrogen (N), starch, fat, calcium (Ca), phosphorus (P), gross energy (GE) and the N-corrected apparent metabolisable energy (AMEn) in broilers fed wheat-based diets was examined in a 35-day trial. A completely randomised design was used, with a 5 × 2 factorial arrangement of 10 treatments (6 replicates per treatment, 8 birds per replicate) involving 5 dietary nutrient densities (VL, very low ND; L, low ND; M, medium ND; H, high ND and VH, very high ND) and 2 F F (mash and pellet). Significant (P < 0.01) interactions between ND and FF were observed for weight gain and feed intake during the whole grow-out period. Birds fed pelleted diets outperformed mash-fed birds at each ND level, but the pellet-induced benefits were of higher magnitude at the lowest ND. Increasing ND lowered (P < 0.001) the feed conversion ratio from 1.540 in VL to 1.381 in VH diets. Increasing dietary ND progressively increased (P < 0.001) the CAID of N, fat and P. Feeding pelleted diets lowered (P < 0.05) the CAID of N, starch, fat and, AMEn. The absolute weight of gizzard was lower (P < 0.05) in pellet-fed birds than mash-fed birds and the opposite was observed (P < 0.05) for the gizzard pH. The current results showed that the performance benefits associated with feeding pelleted diets to broilers are diluted at higher dietary ND, highlighting the importance of determining optimum dietary ND in broiler diets to maximise the expected beneficial outcomes of feeding pelleted diets.
... Svihus et al. (2004) reported that feeding broilers with a pelleted diet increased weight gain and feed intake, and improved FCR compared with those maintained on a mash diet, such results are in line with the findings of the present study. In almost all reports, performance improvement with pelleted diets are alike attributed to increased nutritional density, improved starch digestibility due to chemical changes during pelleting, better nutrient intake, changes in physical feed form, reduced feed waste, and decreased energy expenditure in eating (Amerah et al., 2008;Jafarnejad et al., 2010). It is well known that the use of carbohydrate enriched easily digestible diets in the commercial feeding of broilers with minimal mobility in the densely crowded houses immensely enhances the risk of liver disorders. ...
... The increase of feed intake was necessary for fast growth rate. Moreover, Behnke and Beyer, (2002) reported that the cost of broiler production determined by the feed consumption it was estimate about 70% of the total broiler production cost, the most important factor that could measure about to feed types (pellet, crumble, and mash) that the growth rate influenced by one of them (Jafarnejad et al., 2010). Generally, the diets are used in poultry farms there are three forms, crumble, pellet and Mash. ...
... The low feed intake observed, particularly with birds on toasted I. manni meal diet maybe attributed to the presence of anti-nutritional factors like tannins reported to adversely affect feed intake (Umoren et al., 2007); Suleiman, (2017). Lack of palatability in the feed due to the presence of anti-nutritional factors, dustiness (Umoren et al., 2008;and Effiong et al., 2014) and the bulky nature of the feed sample (Jafarnejad et al., 2010) may have also contributed to the low intake of the feeds with I. manni meal. At the finisher phase, the average daily feed intake of birds fed control diet was statistically (P>0.05) ...
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The aim of the research was to prove that the different feed forms affects the performance and carcass production. In total 240 New Lohmann MB 202 day-old chickens were randomly divided into five groups of treatment for 35 days of rearing period. There were 6 replications with 8 birds per pen. The chickens were fed starter feed at 1-21 days and finisher feed at 22-35 days with different feed forms: mash-mash (MM), mash-crumble (MC), mash-pellet (MP), crumble-crumble (CC), and crumble-pellet (CP). The data were obtained and statistically analyzed by ANOVA, then followed by Duncan’s New Multiple Range Test. Feed form did not give any effect to feed consumption and weight gain but it affected feed conversion (P>0.05). MP kept the highest rate of feed conversion by the end of rearing period. Carcass yield showed that various feed form on days 0-21 did not affect carcass percentage of broiler chickens. The birds which ate pelleted feed on days 22-35 have higher (P>0.05) carcass weight than those consumed mashed and crumbled feeds. It is concluded that chicken fed with mash-pellet feed had the best feed conversion. Besides, the birds which ate pelleted feed on days 22-35 had highest carcass weight.
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An experiment involving 270 straight run one-day-old Hubbard broiler chicks was conducted on floor pens to investigate the effect of different levels of energy and protein on live performance and carcass responses of broilers chicks. Six broiler starter diets with two levels of metabolizable energy (ME) i.e., 2800 and 3000kcal/kg each with three levels of crude protein (CP) i.e., 20, 21 and 22% were offered to birds from hatching to 28d of age. Similarly, six broiler finisher diets with two levels of ME i.e. 3000 and 3200kcal/kg and 3 levels of CP i.e. 16, 17 and 18%, and 18, 19 and 20%, respectively, were offered during 29-42d of age. The chicks were randomly divided into 18 replicate of 15 chicks each and there were 3 replicates under each diet. Feed intake was significantly (p<0.05) high in diet having low ME during both phase, with 20 and 22% CP during starter phase whereas all CP levels showed non-significant effects on feed intake at finisher phase. Low ME and high CP diets showed high feed intake (p<0.05) during starter and finisher phases. Higher weight gains (p<0.05) were observed at low ME diets during the experiment. Dietary CP contents at low ME did not affect the weight gain during starter phase whereas high CP with low ME showed high weight gain in finisher phase. The response of CP and ME was similar for good feed conversion ratio (FCR) as was observed for feed intake and weight gain. No significant differences of dietary treatments were observed on any of the carcass characteristics. From the recent study, it is obvious that low ME and high CP diets promised optimum performance for broiler chicks at both starter and finisher phases.
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This study was conducted to explore the extent to which CP can be reduced in corn-soybean meal broiler starter diets by amino acid supplementation while maintaining adequate performance. Using corn and soybean meal of known composition, diets were formulated by linear programming using a minimum of 107.5% of NRC (1994) amino acid recommendations. No minimum CP was required; as each amino acid became limiting crystalline sources were provided to meet the minimum specification. In sequence these were Met, Thr, Lys, Val, Ile, Arg, Phe, and Trp, resulting in eight treatments ranging from 16.61 to 22.48% CP. All diets contained 0.3% sodium bicarbonate and 0.2% aluminum hydroxide as a buffer and antacid. Three additional treatments utilized potassium sulfate to maintain a minimum dietary electrolyte balance (Na + K - Cl) of 250 meq/kg. Each treatment was fed to twelve replicate groups of six male broiler chicks from 1 to 21 d. Reducing CP below 20% while providing indispensable amino acids resulted in a significant reduction in body weight (BW) and feed conversion ratio (FCR). Crude protein content of freeze-dried carcasses declined and fat content increased as diet CP decreased. Feather content (actual weight or % of BW) was not affected until the CP was reduced to less than 18%. Maintaining dietary electrolyte balance at 250 meq/kg in reduced CP diets had no significant effect on any parameter.
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A six-week trial was conducted to study the effect of decreasing dietary crude protein (CP) level on the performance of broilers in hot climatic conditions. Four experimental rations having CP 23 (control group), 22, 21 and 20%, with optimal amino acid balance were prepared. All the four rations were isocaloric having ME 3200 kcal/kg with Energy: Protein (E:P) 139.0, 146.5, 152.4 and 160 in diets A, B, C and D respectively. One hundred and twenty day-old chicks were randomly distributed into 12 experimental units, each having 10 chicks. Rations were randomly allotted to experimental units such that each unit received three replicates. The experimental diets were fed to birds from day 1st to 42nd. Performance of birds was monitored in terms of weight gain, feed consumption and feed conversion ratio (FCR). At the end of experiment, two birds per each replicate were randomly selected and slaughtered to record the data on carcass yield, breast meat yield, abdominal fat and composition of breast meat. Results of the trial suggested that weight gain was significantly (P<0.01) increased in birds on diets with CP 20 and 21%. Feed consumption and FCR remained un-changed for all the treatment groups. Eviscerated carcass yield was significantly (P<0.05) higher for the group fed on diet with 20% CP. Breast meat yield, abdominal fat and composition of breast meat also remained un-changed. Economic evaluation of the trial revealed that decreasing CP levels from 23 to 20% resulted in reduced feed cost per kg of live weight gain, which clearly indicated that this approach was useful especially in severe summer conditions. The overall picture of the study suggests that dietary protein level of broilers could be reduced from 23 to 20%, with beneficial effects on growth performance and carcass characteristics and increased economic returns in hot environmental conditions, provided that levels of essential amino acids are closely looked after.
Restricted lighting is used commercially to regulate early growth and limit losses associated with sudden death syndrome (SDS), ascites and leg problems. Standard lighting programs may not be suited for broilers marketed at 35 d of age, and promote injury (scratching, i.e., cellulitis) by creating peak feeding periods. This study evaluates four lighting programs, three phases of mash or crumble starter feeding and two diet densities on performance and mortality of broilers marketed at 35 d of age. Two trials each utilized 7200 male broiler (Cobb × Cobb) chicks randomly housed in six (2.75 × 4.90 m) floor pens in each of eight rearing rooms. Four lighting programs were replicated in each trial and consisted of: (a) 23C (23L:1D 0-35 d); (b) 16C (23L:1D 0-3 d, 16L:8D 4-35 d); (c) DDI (delayed decreasing increasing) (23L:1D 0-3 d; 20L:4D 4-6 d, 16L:8D 7-10 d; 8L:16D 11-15 d; 12L:12D 16-20 d; 16L:8D 21-28 d; and 20L:4D 29-35 d); and (d) IL (intermittent lighting, provided in four cycles of 6 h d-1 the same total daily hours of light as the DDI program). Two diet densities were applied for the starter and grower diets; high (ME 3170/3200 kcal; CP 251/210 g) or low (ME 3100/3060 kcal; CP 235/195 g kg-1 starter/grower diet, respectively). The two starter types were fed as combinations of mash (M) or crumble (C): (1) M 0-12 d followed by C 12-21 d; (2) C 0-12 d followed by M 12-21 d; and 3) C 0-21 d. The respective grower/finisher density diets were fed in a pelleted form. By 35 d of age the body weight (BW) of broilers maintained under the DDI lighting program was significantly lower than BW of broilers held under the other lighting programs (16Ca > ILab > 23Cb). Overall (0-35 d) feed conversion (corrected for mortality, but not market weight at 35 d) was highest for broilers reared under the 23Ca > IL ab > DDIb > 16Cc lighting programs, respectively. SDS (%) mortality was highest for IL (1.68a) = 23C (1.53a) ≥ 16C (1.02ab) ≥ DDI (0.80b) lighting programs. There were no significant differences in 35 d BW or feed conversion of broilers fed mash or crumble starter. Feeding mash diets did lower 21 d BW, but this decrease in early growth did not significantly reduce overall mortality. Broilers fed the low as compared to the high-density diets weighed less at 21 d, but weighed significantly more at 35 d, and had a higher (P < 0.05) 0-35 d feed conversion. Low as compared to high-density diets did reduce SDS mortality significantly (0.72 vs. 1.81%, respectively). Lighting programs that do provide variable extended dark periods will alleviate broiler mortality as compared to constant (23 or 16 h ) or intermittent lighting programs. However, these broilers had a significantly lower body weight when marketed at 35 or less days of age.
Director of Feed Services National Grain and Feed Association [Note: This is the fourth in a series of articles on various aspects of feed manufacturing and operations. This edition is the first of a two articles on aspects of feed pelleting operations, and focuses on pelleting quality-assurance procedures and improving pellet quality. The second article will address pellet system equipment operations and pelleting operation efficiency. Feed mill managers may wish to circulate this publication as an education/training tool to appropriate mill employees involved in manufacturing operations.] Pelleting – the most capital-and energy-intensive feed manufacturing operation – is a key driver of feed mill profit-ability. Currently, more than 80 percent of feed for non-ruminant animals in the United States is pelleted. The improved perfor-mance of swine and broilers when fed pelleted feed is well documented [Behnke; 1994] and can be attributed to: De-creased feed wastage; reduced selective feeding; decreased ingredient segregation; less energy spent for prehension; de-struction of pathogenic organisms; increased digestibility; and improved palatability. Pelleting of feed also provides the benefits of: 1) increasing the bulk density of feed; 2) improving feed flowability; and 3) providing opportunities to reduce feed formula costs through the use of alternative feed ingredients.
In a completely randomized design, (with 6 treatments and 3 replications) the effect of feeding mash, pellet and crumble diets and duration time on performance of broilers was studied. 936 Ross broilers randomly allocated to one of following treatments: T1) mash diet in total growing period (TGP) (control diet), T2) pellet diet in TGP, T3) pellet diet in starter and mash diet in other growing period (OGP), T4) mash diet in starter and pellet diet in OGP, T5) crumble diet in first ten days and mash diet in OGP, T6) mash diet in first ten days and pellet diet in OGP. All of chickens were fed with iso energetic and iso nitrogenous diets, for six weeks. In total period (1 to 42 days) feed intake was minimize for T2. Treatments had not different significant effects on weight gain and feed conversion ratio (FCR), but Duncan test were showed a significant difference between T3 and T6 (1859g vs. 2090g and 1.99 vs. 1.73 respectively). The lowest FCR and the highest weight gain were belonged to T6. Carcass, abdominal fat and heart weight percentages to live weight did not significantly differ.
A total of 144 ISA-i757 broiler chicks were fed on mash, pellet and crumble diet in the age duration of 21 to 56 days to compare the performance of broiler on different dietary groups. All the forms of feed were of identical composition as well as same environment and management were provided for all the treatments. The body weight of birds fed on mash, pellet and crumble group from 4th to 8th weeks of age differed significantly (P0.01). Total cost of production was significantly (P< 0.01) less for crumble and this was statistically similar with pellet group. The results of this experiment give an impression that crumble form of feed is better than mash and pellet form for the production of commercial broiler for the age duration of 21 to 56 days.
An experiment was conducted to evaluate the effects of feed form on lysine and dietary energy levels necessary for maximum body weight gain (BWG) and feed efficiency (FE) of male broilers from 14 to 30 d and to determine if birds realize a benefit in productive energy from consuming pelleted diets. A 2 x 3 x 2 factorial treatment arrangement was achieved by feeding diets in two forms (mash and steam-conditioned pellets) with three levels of digestible lysine (0.85, 0.95 and 1.05 % of the diet) and two dietary energy levels (3050 and 3200 kcal ME/kg). Male broiler chicks were provided a nutritionally adequate diet (3100 kcal ME/kg and 22.7% CP) from 0-13 d. Four pens of 32 birds were fed each dietary treatment. Mean body weight and feed consumption were obtained at 14 and 30 d. Average feed intake (AFI) was used to calculate lysine conversion ratio and calories consumed per bird. Pellet-fed birds consumed significantly less digestible lysine (P=0.0061) to achieve the same amount of BWG as the mash-fed birds. Pellet-fed birds exhibited a linear increase in BWG (P=0.0188) with increasing lysine concentrations, while mash-fed birds did not display a growth response at digestible lysine levels greater than 0.85%. Birds fed 3200 kcal ME/kg diets had greater BWG (P=0.006) than those fed 3050 kcal diets. No feed form x dietary energy level interaction was observed for any parameter. Feed form had no effect on AFI (P=0.3784). These findings suggest that improved BWG obtained with pelleted diets may be the result of reduced energy expenditure during meal consumption, indicating that feed form may influence perceived nutrient needs.
In a factorial arrangement of treatments Arbor Acres and Ross male broiler chicks were given four diets with 3,200 kcal ME/kg and four diets with 2,880 kcal ME/kg, two CP levels per energy level (23.1 and 33.6% in the high-energy diet and 21.0 and 29.7 in the low-energy diet) and two Lys levels per CP level per energy level (1.20 and 1.36% per CP level in the high-energy diets and 1.08 and 1.22% per CP level in the low-energy diets). The diets were given to 8 wk of age. Weight gain of Arbor Acres chicks was significantly higher (P less than .05) than that of Ross chicks at 6 and 7 wk of age, but feed to gain ratios were also significantly higher (P less than .05) at 6, 7, and 8 wk of age. Weight gain and feed to gain ratios were significantly better (P less than .05) on the high-energy diets than on the low-energy diets at 6, 7, and 8 wk of age. With equal Lys content, the normal-CP diets gave significantly higher gains (P less than .05) than the high-CP diets at 6, 7, and 8 wk of age. With equal CP content, the high-Lys diets gave significantly more gain (P less than .05) than the normal-Lys diets at 6, 7, and 8 wk of age. Oven-ready and breast meat yields of Ross chicks were significantly higher (P less than .001) compared with those of Arbor Acres chicks at 6, 7, and 8 wk of age and yields of edible organs, skin and fat, and remaining carcass were significantly lower (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)