Xác định mức năng lượng trao đổi, protein thô, lysine và methionine trong khẩu phần của gà Sao (Numida meleagris) nuôi lấy thịt ở Đồng bằng sông Cửu Long (3)_unprotected

MINISTRY OF EDUCATION AND TRAINING
CAN THO UNIVERSITY
------

SUMMARY OF DOCTORAL THESIS
Major: Animal science
Code: 62 62 01 05

NGUYEN DONG HAI

DETERMINING METABOLIZABLE
ENERGY, CRUDE PROTEIN, LYSINE
AND METHIONINE IN DIETS FOR
GROWING GUINEA FOWLS (Numida
Meleagris) IN THE MEKONG DELTA

Can Tho, 2016


The thesis was completed at College of Agriculture and
Applied biology, Can Tho University.
Scientific supervisors: Ass. Prof. Dr. Nguyen Thi Kim Dong

Reviewer 1:..........................................................................
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Reviewer 2:..........................................................................
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Reviewer 3:..........................................................................
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The thesis is defended in front of the University Examination
Council in Can Tho University

Time:…………..……………
Date:…………….……………..

Further information of the thesis could be found at:
1. Learning Resource Center of Can Tho University
2. National library of Vietnam



Chapter 1: INTRODUCTION
1.1 Necessity
Growing Guinea fowl production is developing in the Mekong delta
(MD), and giving high economic efficiency for producers. However,
studies on the digestibiliy of feed ingredients, especially feeds supply
protein are very limited to determine feed source supporting protein
effectively for growing Guinea fowls, as a basis for selecting feed to
formulate diets.
On the other hand, researches in the world and in Vietnam for optimum
metabolized energy (ME) and crude protein (CP) in the diets to feed
growing Guinea fowls gave different results. Specially, the problem with
the reduction in dietary protein and the supplement of crystal lysine (Lys)
and methionine (Met) into the diets to decrease feed cost, influence of bird
waste to environment is an important issue today. Moreover, there is
insufficient information in research and evaluation about digestibility
identifying methods on Guinea fowls to choose the appropriate study
method. For these reasons, the study “Determining metabolizable energy,
crude protein, lysine and methionine in diets for growing Guinea fowls
(Numida meleagris) in the Mekong delta” was carried out.
1.2 Objectives
Evaluating apparent nutrient and animo acid digestibilities in the diets

using four feed ingredients (soybean, soybean extraction meal, fish meal
and catfish by – product meal) to find out the feed ingredients to supply
protein effectively for growing Guinea fowls in the Mekong Delta;
Determining optimum levels of metabolizable energy, crude protein in
the diets for growing Guinea fowls;
Determining optimum levels of lysine and methionine in low CP diets
for feeding growing Guinea fowls.
Evaluating and comparing the total excreta digestibility (TD),
caecectomised bird digestibility (CD) and ileal digestibility (ID) of
nutrients and amino acids efficiently for growing Guinea fowls.
1.3 Subjects and scope
Experiment (Expt) 1: Evaluation of apparent nutrient and amino acid
1


digestibilities of diets with soybean meal and soybean extraction meal for
growing Guinea fowls.
Expt 2: Evaluation of apparent nutrient and amino acid digestibility of
diets with fish meal and catfish by-product meal for growing Guinea
fowls.
Expt 3: Effects of dietary metabolizable energy levels on growth rate,
feed utilization, nutrient intake, carcass quality, nutrient digestibilities in
growing Guinea fowls.
Expt 4: Effects of dietary lysine and methionine levels on growth rate,
carcass quality, nutrient and amino acid digestibilities of growing Guinea
Fowls.
Expt 5: Evaluation of methods to determine nutrients and amino acid
digestibilities for growing Guinea fowls.
1.4 Location and time
These researches were carried out from 2012 to 2015. These

experiments were conducted at the experimental animal farm, 474c/18
Nguyen Van Linh street, Binh An area, Long Hoa ward, Binh Thuy
district, Cantho city; Kiengiang community college; Department of
Animal Products and Animal Feed Analysis, National Institute of Animal
Science (NIAS).
1.5 Novel aspects
Comparison of feeds provide protein efficiently, nutrient and amino
acid digestibilities in diets for feeding growing Guinea fowls.
Determining optimum levels of metabolizable energy, low crude
protein, lysine and methionine in the diets for feeding growing Guinea
fowls.
Evaluation and comparison of total excreta digestibility,
caecectomised bird digestibility and ileal digestibility of nutrients and
animo acids efficiently for growing Guinea fowls.
1.6 Lay-out
The thesis has 244 pages including the introduction, the three-page
content (literature review, material and methods, results and discussion),
2


the conclusion and suggestion, and the appendix. It contains 91 data
tables, 11 figures and 277 references.
Chapter 2: LITERATURE REVIEW
Guinea fowls were brought to Vietnam from the 19th century by French
as scene birds because of their beauty with small number and scattered
distribution. Then, in April 2002, Thuy Phuong Poultry Research Center
(NIAS) imported three lines of Guinea fowls from Godollo Little Animal
Research Institute (Hungary). The results showed that Guinea fowls were
adaptable well and to give the good productivity in Vietnam. In 2009,
from the cooperation program between Cantho University (CTU) and

Godollo Little Animal Research Institute, CTU received 500 Guinea
fowls for researching and transferring to peoplle from other provinces in
MD.
Due to Guinea fowls have been a new object in recent years, so
researches on chicken in our country were quite new, rare, unsystematic.
Most of studies focused on the adaptation of the chicken in climate
condition in Vietnam and based on growth and reproductive
characteristics.
Meanwhile researches and suggestions about requirements of
metabolizable energy, crude protein, lysine and methionine for growing
Guinea fowls were more fluctuating, such as the period of 5-8 weeks of
age with 2.800-3.100 kcal ME/kg, 18-24% CP, 0.95-1.50% lysine and
0.40-0.48% methionine; 9-12 weeks of age with 2.600-3.200 kcal ME/kg,
16-20% CP, 0.79-1.30% lysine and 0.33-0.48% methionine.
Moreover, there has been no research on the supplement of synthetical
lysine and methionine to the diets with low crude protein on Guinea fowls.
This is the tendency that poultry researchers are doing to reduce
expenditure and increase the efficient feed utilisation, while reducing
environmental pollution by reducing excretion of nitrogen in the waste.
The study of the methods of determining nutrient and amino acid
digestibilities on Guinea fowls was very limited, especially amino acid
digestibility. Therefore, the study of methods to determine apparent
nutrient and amino acid digestibility of protein feeds is very necessary.
That helps evaluate appropriate methods to study the digestibility of
3


nutrients and aminio acid of feed ingredients or diets on growing Guinea
fowls. This will select feed ingredients and formulate diets accurately.
Chapter 3: MATERIAL AND METHODS

3.1 Experimental design
Experiment 1: Evaluation of apparent nutrient and amino acid
digestibility of diets with soybean meal and soybean extraction meal
for growing Guinea fowls
The Expt was a completely randomized design on 96 birds at 6 weeks
of age (WOA) with 2 factors and 3 replications. The first factor was the
protein sources of soybean and soybean extraction meal, and the second
one was dietary crude protein (CP) levels of 16, 18, 20 and 22%. There
were 4 birds for each experimental unit. The experiment was carried out
on 2 periods for Guinea fowls at 8 and 10 WOA.
In 8 WOA period, the birds were fed experimental diets for
adaptetation and determined feed intake from 6 to 7 WOA. The feed and
excreta samples were collected in 5 days at 8 WOA. In 10 WOA period,
the birds were adapted and determined feed intake at 9 WOA. The feed
and excreta samples were collected in 5 days at 10 WOA.
The feed ingredients in the Expt were broken rice, soybean (SB) and
soybean extraction meal (SM). Besides, Permasol-500 was added to
drinking water with 2 g/drinking water litre to supply vitamine and
minerals for the chicken.
Table 3.1: Feed ingredient composition of diets in Expt 1 (% as-fed basis)
Ingredient
Broken rice
Soybean
SBM
Total

SB16
76.8
23.2
100

Soybean (SB)
SB18 SB20
71.3
65.7
28.7
34.3
100
100

SB22
60.2
39.8
100

Soybean extraction meal (SM)
SM16 SM18 SM20
SM22
77.1
71.7
66.5
60.9
22.9
28.3
33.5
39.1
100
100
100
100

SBM: soybean extraction meal; SB16; SB18; SB20; SB22; SB16; SM18; SM20; SM22: treatments
using soybean or soybean extraction meal at levels of 16; 18; 20; 22% CP.

Table 3.2: Chemical composition and ME values of diets in Expt 1 (%DM)
Item
DM
CP
EE

SB16
88.3
16.0
5.92

SB18
88.8
18.0
6.87

SB20
89.2
20.0
7.83

Treatment
SB22 SM16
89.6
87.0
22.0

16.0
8.76
2.13

4

SM18
87.1
18.0
2.19

SM20
87.2
20.0
2.26

SM22
87.3
22.0
2.33


Item
CF
NDF
Arginine
Lysine
Methionine
Threonine
ME*

SB16
2.90
12.0
0.91
0.73
0.51
0.45
3,487

SB18
3.43
13.4
1.01
0.81
0.55
0.50
3,484

SB20
3.98
14.9
1.10
0.90
0.60
0.55
3,481

Treatment
SB22 SM16

4.50
2.45
16.4
8.64
1.20
0.95
0.98
0.77
0.63
0.53
0.60
0.50
3,478
3,236

SM18
2.89
9.35
1.06
0.87
0.58
0.57
3,175

SM20
3.31
10.0
1.17
0.96
0.62

0.63
3,116

SM22
3.76
10.8
1.28
1.06
0.66
0.69
3,052

DM: dry matter; CP: crude protein; EE: Extract Ether; CF: crude fiber; NDF: neutral detergent
fiber; ADF: acid detergent fiber; Arg: arginine; Thr: threonine; *: metabolizable energy (kcal/kg
DM).

Experiment 2: Evaluation of apparent nutrient and amino acid
digestibility of diets with fish meal and catfish by-product meal for
growing Guinea fowls
This Expt was a completely randomized design on 96 birds at 6 WOA
with 2 factors and 3 replications. The first factor was the protein sources
of fish meal and catfish by-product meal, and the second one was dietary
crude protein (CP) levels of 16, 18, 20 and 22%. There were 4 birds per
experimental unit. The experiment was carried out on 2 periods for Guinea
fowls at 8 and 10 WOA. In 8 WOA period, the birds were adapted and
determined feed intake from 6 to 7 WOA, and collected feed and excreta
samples in 5 days at 8 WOA. In 10 WOA period, the birds were adapted
and determined feed intake at 9 WOA, and collected feed and excreta
samples in 5 days at 10 WOA. The feed ingredients in the Expt were
broken rice, fish meal (FM) and catfish by - product meal (CM). Besides,

Permasol-500 was added to drinking water with 2 g/drinking water litre
to supply vitamine and minerals to the chicken.
Table 3.3: Feed ingredient composition of diets in Expt 2 (% as-fed basis)
Ingredients
Broken rice
FM
CM
Total

FM16
76.8
23.2
100

Fish meal (FM)
FM18 FM20
71.3
65.7
28.7
34.3
100
100

FM22
60.2
39.8
100

Catfish by product meal (CM)
CM16 CM18

CM20 CM22
77.1
71.7
66.5
60.9
22.9
28.3
33.5
39.1
100
100
100
100

FM16; FM18; FM20; FM22; CFM16; CFM18; CFM20; CFM22: treaments using fish meal or
catfish by-product meal with CP levels in diet of 16; 18; 20; 22%.

5


Table 3.4: Chemical composition and ME values of diets in Expt 2 (% DM)

Item
DM
CP
EE
CF
NDF
Lys
Met

Thr
ME*

Treatment
FM16
91.0
16.0
1.86
1.07
6.07
0.84
0.59
0.58
3,353

FM18
91.0
18.0
2.18
1.05
6.16
0.97
0.65
0.67
3,319

FM20
91.0
20.0
2.49

1.04
6.24
1.09
0.72
0.75
3,286

FM22
91.0
22.0
2.80
1.03
6.33
1.21
0.78
0.83
3,253

CM16

CM18

CM20

CM22

91.5
16.0
2.78
1.11

6.37
0.74
0.56
0.53
3,433

91.5
18.0
3.32
1.11
6.54
0.84
0.62
0.61
3,419

91.6
20.0
3.86
1.10
6.70
0.94
0.68
0.68
3,405

91.7
22.0
4.36
1.10

6.86
1.03
0.74
0.75
3,392

DM: dry matter; CP: crude protein; EE: Extract Ether; CF: crude fiber; NDF: neutral detergent
fiber; ADF: acid detergent fiber; Arg: arginine; Thr: threonine; *: metabolizable energy (kcal/kg
DM).

Experiment 3: Effects of dietary metabolism energy levels on growth
rate, feed utilization, nutrient intake, carcass quality, and nutrient
digestibilities in growing Guinea fowl
This Expt included feeding experiment and digestibility experiment.
Feeding experiment
From 5 to 8 weeks of age (WOA)
This Expt was a completely randomized design with 5 treatments and
3 replications on 150 birds at 5 WOA. The treatments had the dietary ME
levels of 2.800; 2.900; 3.000; 3.100; 3.200 kcal/kg DM with 20% CP
level. There are 10 birds in each experimental unit. Chemical composition
(CC) and ME value in diets of Expt 3 were showed in Table 3.5.
Table 3.5: Chemical composition (% DM) of diets of Expt 3 from 5 to 8 weeks
old Guinea fowls.
Item (%)
DM
OM
CP
EE
CF
NDF

ME

ME2800
89.9
87.5
20.0
12.1
6.48
21.4
2,800

ME2900
89.5
88.6
20.0
11.2
5.77
20.2
2,900

Treatment
ME3000
89.1
89.8
20.0
10.2
5.03
18.6
3,000

ME3100
88.7
90.9
20.0
9.14
4.25
17.1
3,100

ME3200
88.4
91.8
20.0
8.29
3.62
16.2
3,200

ME2800; ME2900; ME3000; ME3100; ME3200: treatments had ME levels of 2.800; 2.900; 3.000;
3.100 và 3.200 kcal/kg DM.

6


From 9 to 14 weeks of age
The Expt was a completely randomized design with 5 treatments and
3 replications on 150 birds at 9 WOA. The treatments had the dietary ME
levels of 2.900; 3.000; 3.100; 3.200 and 3.300 kcal/kg DM with 18% CP
level. There are 10 birds in each experimental unit. Chemical composition
and ME value in diets of Expt 3 from 9 to 14 WOA were showed in Table

3.6.
Table 3.6: Chemical composition and ME in diets from 9 to 14 WOA
Item (%)
DM
OM
CP
EE
CF
NDF
ME (kcal/bird/day)

ME2900
89.4
89.0
18.0
10.8
5.80
20.0
2,900

ME3000
89.1
90.0
18.0
10.0
5.17
19.1
3,000

Treatment

ME3100
88.7
91.3
18.0
8.87
4.32
17.1
3,100

ME3200
88.3
92.5
18.0
7.94
3.60
15.7
3,200

ME3300
87.9
93.6
18.0
6.98
2.88
14.3
3,300

ME2900; ME3000; ME3100; ME3200; ME3300: treatments had ME level with 2,800; 2,900; 3,000;
3,100 và 3,200 kcal/kg DM.

Digestibility experiment
This Expt added to the conclusion of the feeding Expt from the Expt
3. It was carried out at 8 and 10 WOA Guinea fowls. It was designed to
similar to the feeding growing Expt, but having 4 birds in each pen. Time
and procedure resemble to the Expt 1.
Experiment 4: Effects of dietary lysine and methionine levels on
growth rate, carcass quality, nutrient and amino acid digestibilities of
growing Guinea Fowls
This Expt included feeding Expt and digestibility Expt
The feeding experiment
From 5 to 8 weeks of age (WOA)
This trial was designed in a completely randomized design with 6
treatments and 3 replications. Each experimental unit had ten Guinea
fowls at 5 WOA. The treatments consisted of
1.04L0.46M: the diet had 20%CP without supply crystal Lys and Met
to the diet, and had 1.04% Lys and 0.46% Met.
7


0.91L0.40M: the diet had 18%CP without supply crystal Lys and Met
to the diet, and had 0.91% Lys and 0.40% Met.
1.10L0.45M: the diet had 18%CP with supplying crystal Lys and Met
to the diet, and had 1.10% Lys and 0.45%Met.
1.10L0.45M: the diet had 18%CP with supplying crystal Lys and Met
to the diet, and had 1.10% Lys and 0.55% Met.
1.40L0.45M: the diet had 18%CP with supplying crystal Lys and Met
to the diet, and had 1.40% Lys and 0.45% Met.
1.40L0.55M: the diet had 18%CP with supplying crystal Lys and Met
to the diet, and had 1.40% Lys and 0.45% Met.
The feed ingredients consisted of broken rice, corn, rice bran, fish

meal, soybean, DCP, crystal lysine and methionine. The chemical
composition of diets from 5 to 8 WOA were showed in Table 3.7.
Table 3.7: Chemical composition (%DM) of experimental diets of Guinea
fowls from 5 to 8 WOA
Item, %

DM
OM
CP
EE
CF
NDF
Lysine
Methionine
ME (kcal/kg DM)

1.04L
0.46M
91.2
89.3
20.0
9.36
5.69
17.4
1.04
0.46
3,098

Treatment
1.10L

1.10L
0.45M
0.55M
90.1
90.2
89.4
89.3
17.0
17.0
7.52
7.53
4.72
4.73
16.4
16.5
1.10
1.10
0.45
0.55
3,099
3,099

0.91L
0.40M
90.0
89.7
17.0
7.53
4.72
16.2

0.91
0.40
3,101

1.40L
0.45M
90.3
89.0
17.0
7.53
4.74
16.8
1.40
0.45
3,101

1.40L
0.55M
90.3
88.9
17.0
7.53
4.74
16.9
1.40
0.55
3,100

From 9-14 weeks of age
This trial was a randomly complete design with six treatments with six

diets and three replications. Each experimental unit had ten Guinea fowls
at 9 WOA. The treatments consisted of
0.98L0.43M: the diet had 18%CP without supply crystal Lys and Met
to the diet, and had 0.98% Lys and 0.43% Met.
0.80L0.37M: the diet had 15%CP without supply crystal Lys and Met
to the diet, and had 0.80% Lys and 0.37% Met.
8


0.90L0.40M: the diet had 15%CP with supplying crystal Lys and Met
to the diet, and had 0.90% Lys and 0.40% Met.
0.90L0.50M: the diet had 15%CP with supplying crystal Lys and Met
to the diet, and had 0.90% Lys and 0.40% Met.
1.20L0.40M: the diet had 15%CP with supplying crystal Lys and Met
to the diet, and had 1.20% Lys and 0.40% Met.
1.20L0.40M: the diet had 15%CP with supplying crystal Lys and Met
to the diet, and had 1.20% Lys and 0.50% Met.
Table 3.8: Chemical composition (%DM) of experimental diets of
Guinea fowls from 9 to 14 WOA
Item, %

DM
OM
CP
EE
CF
NDF
Lysine
Methionine
ME (kcal/kg DM)

0.98L
0.43M
89.9
90.9
18.0
7.38
4.46
15.0
0.98
0.43
3,199

Treatment
0.90L
0.90L
0.40M
0.50M
89.3
89.3
91.5
91.4
15.0
15.0
6.27
6.27
4.15
4.15
14.8
14.9

0.90
0.90
0.40
0.50
3,200
3,201

0.80L
0.37M
89.2
91.7
15.0
6.26
4.14
14.7
0.80
0.37
3,200

1.20L
0.40M
89.4
91.1
15.0
6.26
4.15
15.1
1.20
0.40
3,199

1.20L
0.50M
89.4
91.0
15.0
6.27
4.16
15.2
1.20
0.50
3,199

Digestibility experiment
This trial was conducted at two periods at 8 and 10 weeks old birds.
The trial was silimilar to the feeding trial of the Expt 4, but had four birds
for each experimental unit. Feed and excreta samples were collected in 5
days at eight and ten week for each experimental period.
Experiment 5: Evaluation of methods to determine nutrients and
amino acid digestibilities for growing Guinea fowls.
The Expt was a randomly complete design with three treatments and
five replications on 60 Guinea fowls at 10 WOA. The treatments were
total tract, caecetomised, and ileal digestibilities. There are 4 birds in each
experimental unit. The Expt was conducted in three weeks and similar to
the Expt 1.

9


Table 3.9: Chemical composition (% DM) of experimental diet

Item
Value (%)
Item
Value (%)
DM
88.8
NDF
12.5
OM
93.7
ADF
5.22
CP
18.0
Lysine
1.20
EE
4.98
Methionine
0.38
CF
3.40
ME (kcal/kg DM)
3,200
DM: dry matter; CP: crude protein; EE: Extract Ether; CF: crude fiber; NDF: neutral
detergent fiber; ADF: acid detergent fiber; ME: metabolizable energy.

Measurements in the digestibility Expt 1, 2, 3, 4 and 5, such as dry
matter (DM), ash, crude protein (CP), ether extract (EE), crude fiber (CF),
neutral detergent fiber (NDF), acid detergent fiber (ADF), amino acid

(AA) of residual feed and excreta samples, comsumed feed, digestibility
of nutrients and amino acids, nitrogen retention.
Measurements in the feeding Expt 3, 4 consisted of feed intakes,
comsumed nutrients, body weight (BW), daily weight gain (DWG), feed
conversation rate (FCR), carcass weight, meat nutrients of Guinea fowls
in the Expts, and economic return.
3.2 Data analysis
All of data of the thesis organized by Microsoft Office Excel 2010 and
then analyzed by Minitab program version 16.1.0.0 (Minitab, 2010). The
analysis of variance by General Leaner Model of Minitab 16.1.0.0. When
the F-test was signigicantly (P<0.05), the Tukey test was used to find
significant differentces between the treatment averages. Paired T-test was
used to compare average values at two old periods.

Chapter 4: RESULTS AND DISCUSSIONS
4.1 Experiment 1: Evaluation of apparent nutrient and amino acid
digestibility of diets with soybean meal and soybean extraction meal
for growing Guinea fowls
At the 8-week old period
Table 4.1: Apparent nutrient and amino acid digestibilities (%)
Items

DM
OM

CP source
SB
SM
81.1
82.3

80.5
81.9

CP
16
79.3c
80.7c

CP level
CP
CP
18
20
80.4bc
81.9a
81.8bc
83.5a

10

P
CP
22
81.6ab
82.4ab

CP
sources
0.132

0.321

CP
levels
0.001
0.001


Items

CF
NDF
Arginine
Lysine
Methionine
Threonine
Valine

CP source
SB
SM
34.9
47.7
87.2
87.6
83.7
81.6
79.9

CP

16
31.7b
43.8b
83.5c
84.8c
79.2c
75.5c
74.0c

36.5
47.9
87.1
88.6
84.0
82.2
79.0

CP level
CP
CP
18
20
34.7ab
39.8a
47.7ab
50.8a
86.0b 89.2a
87.5b 90.1a
83.0b 87.2a
80.5b 85.6a

77.8b 83.7a

P
CP
22
36.6ab
48.9ab
89.9a
89.9a
86.0a
85.7a
82.3a

CP
sources
0.259
0.866
0.851
0.031
0.583
0.392
0.372

CP
levels
0.008
0.009
0.001
0.001
0.001

0.001
0.001

SB: soybean; SM: soybean extraction meal; DM: dry matter; OM: organic matter; CF: crude fiber;
NDF: neutral detergent fiber; values in rows with different superscript letters are significant different
(P<0.05).

Table 4.2: Nitrogen retention (g/bird/day) of birds at 8 weeks of age
Item

NR
NR/NI, %
NR/W0,75*

CP source
SB
SM
0.66
48.6
0.98

0.65
48.5
0.97

CP
16
0.47c
43.3c
0.71c

CP level
CP
CP
18
20
0.60b 0.75a
47.5bc 53.1a
0.90b 1.11a

P
CP
22
0.79a
50.3ab
1.16a

CP
sources
0.779
0.911
0.837

CP
levels
0.001
0.001
0.001

NI: nitrogen intake; NR: nitrogen retention; W0,75: metabolic weight; *: g/kgW0.75;

Values in rows with different superscript letters are significant different (P<0.05).

The results of Table 4.1 and Table 4.2 showed that the apparent
nutrient and almost amino acid digestibilities, nitrogen retention of the
treatments with soybean were equal to those with soybean-extraction meal
(P>0.05). The nutrient and amino acid digestibility values, nitrogen
retention were the highest (P<0.05) in the CP20 treatment.
At 10-week old period
Table 4.3: Apparent nutrient and amino acid digestibilities (%)
Item

DM
OM
CF
NDF
Arginine
Lysine
Methionine
Histidine
Threonine
Valine

CP source
SB
82.1
83.6
42.2
51.4
90.3
89.4

87.2
76.1
82.3
78.9

SM
81.9
83.2
40.1
49.9
88.2
89.4
87.2
83.2
85.4
80.9

CP level
CP16
80.1b
81.5b
35.3b
45.5b
85.4b
84.5b
82.0b
71.2b
75.7b
71.3b

CP18
82.5a
83.9a
42.4a
52.2ab
89.8a
90.3a
87.9a
83.0ab
84.6a
81.7a

CP20
82.8a
84.4a
43.6a
52.6a
89.8a
90.6a
89.4a
85.2a
87.4a
82.6a

P
CP22
82.6a
83.8a
43.2a
52.2ab

91.8a
92.2a
89.4a
79.1ab
87.6a
84.0a

CP sources
0.389
0.236
0.250
0.374
0.011
0.913
0.980
0.045
0.031
0.275

Values in rows with different superscript letters are significant different (P<0.05).

11

CP levels
0.001
0.001
0.009
0.023
0.001
0.001

0.001
0.038
0.001
0.001


Table 4.4: Nitrogen retention (g/bird/day) of birds at 10 weeks of age
Item

NR
NR/NI, %
NR/W0,75*

CP source
(M)
SB
SM
1.04
66.9
1.07

1.04
67.8
1.07

CP
16
0.79b
61.1c
0.82b

CP level
(N)
CP
CP
18
20
1.10a 1.12a
75.6a 69.0b
1.14a 1.15a

P
CP
22
1.15a
63.7c
1.18a

CP
sources
0.877
0.264
0.895

CP
levels
0.001
0.001
0.001

NI: nitrogen intake; NR: nitrogen retention; W0,75: metabolic weight; *: g/kgW0.75;
Values in rows with different superscript letters are significant different (P<0.05).

The results of Table 4.3 and Table 4.4 showed that the nutrient, and
almost amino acid digestibility values, nitrogen retention of the treatments
with soybean were equal to those with soybean-extraction meal (P>0.05).
The nutrient and amino acid digestibility values, nitrogen retention of the
CP18, CP20 and CP22 treatments were higher (P<0.05) than those of the
CP16 treatment. However, when increasing CP level was higher 18%CP
in the diets, nutrient and animo acid digestibilities, nitrogen retention were
not significantly different (P>0.05) among these treatments.
4.2 Experiment 2: Evaluation of apparent nutrient and amino acid
digestibility of diets with fish meal and catfish by-product meal for
growing Guinea fowls
At 8 week-old period
Table 4.5: Apparent nutrient and amino acid digestibilities (%)
Item
DM
OM
CF
NDF
Arginine
Lysine
Methionine
Threonine
Valine

CP source

CP level

P

FM

CM

CP16

CP18

CP20

CP22

CP
sources

CP
levels

80.1
83.8
40.7
59.5
82.4
87.2
81.8
78.8
74.8

79.4
83.4
39.4
50.7
75.8
80.1
74.7
72.1
61.8

78.0c
82.1c
35.4c
50.4b
71.3c
76.3c
69.3c
64.3c
53.2c

78.8bc
83.3bc
37.6bc
52.8b
76.6bc
82.7b
76.8b
72.7b
63.1bc

81.7a
84.8a
45.1a
59.9a
82.8ab
86.5a
81.8a
80.6a
74.1ab

80.5ab
84.2ab
42.1ab
57.3ab
85.7a
89.1a
85.1a
84.3a
82.7a

0.168
0.266
0.364
0.001
0.003
0.001
0.001
0.002
0.002

0.001
0.001
0.001
0.005
0.001
0.001
0.001
0.001
0.001

FM: fish meal; CM: catfish by-product meal; DM: dry matter; OM: organic matter; CF: crude fiber;
NDF: neutral detergent fiber; values in rows with different superscript letters are significant

different (P<0.05).

12


Table 4.6: Content of nitrogen retention of 8-week old birds (g/bird/day)
Item
CP source
CP level
P

NR
NR/NI, %
NR/W0,75

FM

CFM

CP16

CP18

CP20

CP22

CP
sources

0.83
66.6
1.07

0.76
60.2
0.99

0.56c
54.5d
0.75c

0.69b
59.2c
0.91b

0.98a
74.7a
1.26a

0.93a
65.1b
1.21a

0.001
0.001
0.006

CP
levels
0.001
0.001
0.001

NI: nitrogen intake; NR: nitrogen retention; W0,75: metabolic weight; *: g/kgW0.75;
Values in rows with different supercript letters are significant different (P<0.05).

The results of Table 4.5 and Table 4.6 indicated that the apparent CF,
NDF, almost amino acid digestibilities, and nitrogen retention of the
treatments with fish meal were higher (P<0.05) than those of the
treatments with catfish by-product meal. When increasing CP levels in the
diets, the apparent nutrient and animo acid digestibility values, nitrogen
retention of the treatments rose and had the highest for the CP20 treatment
(P<0.05).
At 10-week old period
Table 4.7: Apparent nutrient and AA digestibilities (%) of 10-week old birds

Item

CP source

DM
OM
CF
NDF
Arginine
Lysine
Methionine
Threonine
Valine

FM
83.8
86.1
49.5
60.9
84.2
89.3
85.1
84.8
82.5

CM
81.5
84.3
44.9
55.7

77.2
83.1
78.2
77.3
69.6

CP level
CP16
81.2b
83.7b
41.3b
52.0b
73.4b
79.6b
73.5b
71.0b
62.7b

CP18
84.0a
85.8a
49.2a
58.7a
84.7a
87.8a
83.7a
84.7a
79.8a

CP20

84.1a
86.0a
50.4a
63.5a
85.3a
89.3a
85.7a
86.3a
83.4a

P
CP22
81.3b
85.3ab
47.9ab
59.0a
79.4ab
88.1a
83.6a
82.2a
78.3a

CP sources
0.001
0.001
0.016
0.006
0.004
0.001
0.001

0.001
0.001

CP levels
0.001
0.011
0.008
0.001
0.003
0.001
0.001
0.001
0.001

FM: fish meal; CM: catfish by-product meal; DM: dry matter; OM: organic matter; CF: crude fiber;
NDF: neutral detergent fiber; values in rows with different superscript letters are significant different
(P<0.05).

Table 4.8: Nitrogen retention content (g/bird/day) of 10 week-old birds
Item
NR
NR/NI,%
NR/W0,75

CP source
FM
CM
1.16
1.10
76.9

72.6
1.14
1.08

CP16
0.90c
70.7b
0.90b

CP level
CP18 CP20
1.15b 1.23a
80.4a 77.1a
1.13a 1.19a

P
CP22
1.24a
70.8b
1.22a

CP sources
0.008
0.001
0.039

CP levels
0.001
0.001
0.001

NI: nitrogen intake; NR: nitrogen retention; W0,75: metabolic weight; *: g/kgW0.75; values in rows with
different superscript letters are significant different (P<0.05).

13


The results of Table 4.7 and Table 4.8 showed that DM, OM, EE, CF,
NDF, almost amino acid digestibilities, and nitrogen retention of the
treatments with fish meal were significantly higher (P<0.05) than those of
catfish by-product meal. The apparent DM, OM, CF, NDF, almost amino
acid digestibilities, nitrogen retention of the CP18, CP20 and CP22
treatments were higher (P<0.05) than CP16. However, those values on
CP18 treatment were not different significantly (P>0.05) from CP20 and
CP22 treatments.
4.3 Expirement 3: Effects of dietary metabolizable energy levels on
growth rate, feed utilization, nutrient intake, carcass quality, nutrient
digestibilities in growing Guinea fowl
Feeding experiment
From 5 to 8 weeks of age (WOA)
Table 4.9: Daily nutrient intakes (g/bird) of Guinea fowls from 5-8 WOA
Item
DM
OM
CP
EE
CF
NDF
ME

ME2800
44.2c
38.7c
8.83c
5.34a
2.86a
9.47a
124c

ME2900
49.1bc
43.5bc
9.84bc
5.49a
2.84ab
9.90a
142bc

Treatment
ME3000
53.1ab
47.7ab
10.6ab
5.42a
2.67ab
9.90a
159b

ME3100
58.2a

52.9a
11.7a
5.32a
2.47b
9.92a
180a

ME3200
50.2bc
46.2b
10.1bc
4.17b
1.82c
8.14b
161ab

P
0.001
0.001
0.001
0.001
0.001
0.005
0.001

DM: dry matter; OM: organic matter; CF: crude fiber; NDF: neutral detergent fiber; Values in rows
with different superscript letters are significant different (P<0.05)

Table 4.10: Final live weight (FW), daily weight gain (DWG) and feed
conversation ratio (FCR) of birds from 5 to 8 WOA

Item
FW, g/bird
DWG, g/bird/day
FCR

ME
2800
849c
15.2c
3.25

ME
2900
873bc
16.0bc
3.42

Treatment
ME
3000
905b
17.2b
3.46

P
ME
3100
979a
19.9a
3.31

ME
3200
919b
17.7b
3.21

0.001
0.001
0.361

Values in rows with different superscript letters are significant different (P<0.05)

Table 4.9 and Table 4.10 showed that DM, OM, CP, and ME intakes,
final body weight (FW), daily weight gain (DWG) increased from the
ME2800 to the ME3100, and those highest values were significantly
(P<0.05) in the ME3100 treatment.
14


From 9 to 14 weeks of age (WOA)
Table 4.11: Nutrient intakes (g/bird/day) of birds from 9 to 14 WOA
Item
DM
OM
CP
EE
CF
NDF
ME, kcal/bird/day

ME
2900
48.2e
42.9e
8.69e
5.22ab
2.80a
9.63b
140d

ME
3000
53.0d
47.8d
9.56d
5.30a
2.74a
10.1a
159c

Treatment
ME
3100
56.1c
51.2c
10.1c
4.98c
2.42b
9.57b

174b

ME
3200
64.3a
59.4a
11.6a
5.11bc
2.32c
10.1a
206a

P

ME
3300
61.5b
57.6b
11.1b
4.29d
1.77d
8.79c
203a

0.001
0.001
0.001
0.001
0.001
0.001

0.001
DM: dry matter; OM: organic matter; CF: crude fiber; NDF: neutral detergent fiber; values in rows
with different superscript letters are significant different (P<0.05).

The results of Table 4.11 showed that DM, OM, CP and ME intakes
increased from the ME2900 treatment to the ME3200 treatment, and got
the highest values in the ME3200 treatment (P<0.05).
Table 4.12: Final live weight (FW), daily weight gain (DWG) and feed
conversation ratio (FCR) of Guinea fowls from 9 to 14 WOA
Item
FW, g/bird
DWG, g/bird/day
FCR
Total penses*
Total income *
Profit*

ME
2900
1,545d
14.8d
3.65b
125,667
169,968
44,301

ME
3000
1,609c
16.3c

3.65b
128,839
177,027
48,187

Treatment
ME
ME
3100
3200
1,660b
1,727a
17.5b
19.1a
b
3.61
3.81ab
131,569 136,909
182,545 189,988
50,976
53,079

P
ME
3300
1,669b
17.7b
3.94a
136,880
183,627

46,747

0,001
0.001
0.004
-

*: Vietnam dong; values in rows with different superscript letters are significant different (P<0.05).

The results of Table 4.12 indicated that final live weight, profit of the
ME3200 treatment were the highest significantly (P<0.05).
Table 4.13: Carcass parameters of Guinea fowls in Expt 3 (g/bird)
Treatment

Item
LW
CW
DP, %
BLP, %

ME2900
1.660d
1.168c
70.4
46.0

ME3000
1.690c
1.190c
70.4

46.1

ME3100
1.728b
1.226b
71.0
46.3

P
ME3200
1.770a
1.260a
71.2
48.5

ME3300
1743b
1.230b
70.6
47.1

0.001
0.001
0.269
0.068

LW: live weight; CW: carcass weight; DP: dressing percentage; BLP: breast and leg percentage;
values in rows with different supercript letters are significant different (P<0.05).

15

Table 4.13 showed that the live weight and carcass weight were the
highest (P>0.05) in the ME3200 treatment. The percentage of carcass,
percentage of breast and thigh weight were similar to them (P>0.05).
Digestibility experiment
At the 8-week old period
Table 4.14: Apparent nutrient digestibilities (%) of 8-week old birds
Item
DM
OM
EE
CF
NDF
ADF

ME2800
71.2d
72.9d
80.7b
25.3c
30.7b
27.6b

ME2900
74.1c
77.7c
82.8ab
26.5bc
34.7b

29.4b

Treatment
ME3000
78.7b
80.7b
83.3ab
30.4ab
38.5ab
35.4ab

ME3100
82.8a
84.2a
85.0a
34.2a
45.6a
39.4a

ME3200
80.5ab
83.1ab
84.9a
31.6a
45.3a
39.3a

P
0.001
0.001

0.024
0.001
0.003
0.005

DM: dry matter; OM: organic matter; CF: crude fiber; NDF: neutral detergent fiber; ADF: acid
detergent fiber; values in rows with different superscript letters are significant different (P<0.05).

Table 4.15: Content of nitrogen retention (g/bird/day) at 8-week old birds
Item
NR
NR/NI, %
NR/W0,75 *

ME2800
0.76d
53.9d
0.99d

ME2900
0.85c
60.8c
1.09c

Treatment
ME3000
0.90bc
64.2bc
1.13bc

ME3100
1.01a
72.0a
1.25a

ME3200
0.95ab
68.1ab
1.19ab

P
0.001
0.001
0.001

NI: nitrogen intake; NR: nitrogen retention; W0,75: metabolic weight; *: g/kgW0.75; Values in rows with
different supercript letters are significant different (P<0.05)

The results of Table 4.14 and Table 4.15 indicated that the apparent
DM, OM, CF, NDF and ADF digestibilities, nitrogen retention got the
highest values (P<0.05) for the ME3100 treatment.
At 10 week-old period
Table 4.16: Apparent nutrient digestibilities (%)
Item
DM
OM
EE
CF
NDF
ADF

ME2900
72.9d
74.5d
83.7
28.3b
37.0c
30.5c

ME3000
78.2c
79.9c
84.4
29.6b
41.6bc
32.3bc

Treatment
ME3100
80.6bc
82.5bc
85.5
30.6ab
47.2b
40.5ab

ME3200
84.0a
85.6a
85.9

39.8a
59.3a
42.7a

ME3300
81.9ab
84.1ab
85.8
40.0a
58.8a
41.6a

P
0.001
0.001
0.102
0.004
0.001
0.002

DM: dry matter; OM: organic matter; CF: crude fiber; NDF: neutral detergent fiber; ADF: acid
detergent fiber; values in rows with different superscript letters are significant different (P<0.05)

16


Table 4.17: Content of nitrogen retention at 10-week old birds (g/bird/day)
Item
NR
NR/NI, %

NR/W0,75

ME2900
0.86d
58.5d
0.85d

Treatment
ME3100 ME3200
1.16b
1.27a
78.7b
85.6a
1.12b
1.21a

ME3000
1.06c
72.0c
1.03c

ME3300
1.19b
80.9b
1.15ab

P
0.001
0.001
0.001

NI: nitrogen intake; NR: nitrogen retention; W0,75: metabolic weight; *: g/kgW0.75; values in rows with
different superscript letters are significant different (P<0.05)

The results of Table 4.16 and Table 4.17 showed that apparent DM,
OM, CF, NDF and ADF digestibilities, nitrogent retention had the higest
values (P<0.05) in the ME3200 treatment.
4.4 Experiment 4: Effects of dietary lysine and methionine levels on
growth rate, carcass quality, nutrient and amino acid digestibilities of
growing Guinea Fowls
Feeding experiment
From 5 to 8 week of age (WOA)
Table 4.18: Nutrient intakes (g/bird/day) of birds from 5 to 8 WOA
Item

DM
CP
EE
CF
NDF
Lysine
Methionine
ME

Treatment
1.04L
0.46M
54.9
11.0a
5.14a

3.12a
9.57a
0.57b
0.25b
170

0.91L
0.40M
52.6
8.94b
3.96b
2.48b
8.54b
0.48c
0.21d
163

1.10L
0.45M
52.0
8.85b
3.91b
2.46b
8.54b
0.57b
0.23c
161

1.10L
0.55M

52.0
8.84b
3.91b
2.46b
8.58b
0.57b
0.28a
161

1.40L
0.45M
52.8
8.98b
3.98b
2.50b
8.89b
0.74a
0.24bc
164

1.40L
0.55M
53.0
9.01b
3.99b
2.51b
8.94b
0.74a
0.29a
164

P
0.153
0.001
0.001
0.001
0.001
0.001
0.001
0.158

DM: dry matter; CP: crude protein; EE: extract ether; CF: crude fiber; NDF: neutral detergent fiber;
values in rows with different superscript letters are significant different (P<0.05).

Table 4.19: Final live weight (FW), daily weight gain (DWG) và feed
conversation rate (FCR) of Guinea fowls from 5 to 8 WOA
Item

FW, g/bird
DWG, g/bird
FCR

Treatment
1.04L
0.46M
942a
19.1a
3.16d

0.91L

0.40M
827d
14.9d
3.91a

1.10L
0.45M
862c
16.2c
3.63b

1.10L
0.55M
881c
16.9c
3.42bc

1.40L
0.45M
905b
17.8b
3.29cd

1.40L
0.55M
938a
18.9a
3.10d

Values in rows with different superscript letters are significant different (P<0.05)

17

P
0.001
0.001
0.001


The results of Table 4.19 showed that final live weight of 8-week old
Guinea fowls were the highest values (P<0.05) in the 1.04L0.46M and the
1.40L0.55M.
From 9 to 14 weeks of age (WOA)
Table 4.20: Nutrient intakes (g/bird/day) of Guinea fowls from 9 to 14 WOA
Item

DM
CP
EE
CF
NDF
Lys
Met
ME

Treatment
0.98L
0.43M
60.6
10.9a

4.47a
2.70
9.06
0.60b
0.26b
194

0.80L
0.37M
62.1
9.32b
3.89b
2.57
9.10
0.50c
0.23c
199

0.90L
0.40M
63.4
9.52b
3.97b
2.63
9.39
0.57b
0.25bc
203

0.90L

0.50M
62.2
9.34b
3.90b
2.58
9.28
0.56bc
0.31a
199

1.20L
0.40M
63.9
9.59b
4.00b
2.66
9.64
0.77a
0.26bc
204

P

1.20L
0.50M
60.6
9.08b
3.80b
2.52
9.20

0.73a
0.30a
194

0.516
0.001
0.004
0.405
0.467
0.001
0.001
0.513

DM: dry matter; CP: crude protein; EE: extract ether; CF: crude fiber; NDF: neutral detergent fiber;
values in rows with different supercript letters are significant different (P<0.05)

Table 4.21: Final live weight (FW), daily weight gain (DWG), feed
conversation rate (FCR) and profit of Guinea fowls from 5 to 14 WOA
Item
Treatment
P
0.98L
0.80L
0.90L
0.90L
1.20L
1.20L
0.43M 0.37M 0.40M 0.50M 0.40M 0.50M
FW, g/bird
1,690a

1,527c
1,598b
1,604b
1,626b
1,688a 0.001
a
c
b
b
b
DWG, g/bird/day
18.6
14.7
16.4
16.5
17.1
18.5a 0.001
c
a
b
b
b
FCR
3.63
4.73
4.34
4.21
4.19
3.65c 0.001
Total expense*

Total income*

137,306
185,940
48,635

134,784
167,952
33,167

135,881
175,747
39,866

135,901
176,407
40,506

136,993
178,860
41,867

135,860
185,713
49,853

Profit*
*: VND; values in rows with different superscript letters are significant different (P<0.05).

-

-

Table 4.22: Carcass parametters of Guinea fowls (g/bird)
Item

Final live weight
Carcass weight
Breast percentage, %
Thigh percentage, %

0.98L
0.43M
1,700a
1,264a
23.6
23.2

0.80L
0.37M
1,532c
1,101c
22.5
22.7

Treatment
0.90L
0.90L
0.40M 0.50M
1,615b

1,621b
1,169b
1,187b
22.7
23.0
22.8
22.8

1.20L
0.40M
1,623b
1,190b
23.4
23.0

Values in rows with different supercript letters are significant different (P<0.05)

18

1.20L
0.50M
1,695a
1,257a
23.5
23.1

P
0.001
0.001
0.180

0.913


The results of Table 4.21 and Table 4.22 showed that final live weight,
carcass weight were the highest (P<0.05) in the 0.98L0.43M and the
1.20L0.50M treatments. The breast and thigh percentage of the treatments
were similar (P>0.05).
Digestibility experiment
At 8 week-old period
Table 4.23: Nutrient digestibilities (%) of birds at 8 weeks of age
Item

Treatment
1.04L
0.91L
1.10L
1.10L
1.40L
1.40L
0.46M
0.40M
0.45M
0.55M
0.45M
0.55M
DM
80.6a
78.4d
78.8cd
79.1cd

79.3bc
80.1ab
OM
84.1a
79.9d
80.6cd
81.1cd
81.7bc
83.1ab
EE
85.4
83.5
83.7
83.7
83.7
83.8
CF
26.7
23.8
23.2
23.9
25.2
28.8
NDF
45.3a
34.0c
35.8c
37.1bc
37.8bc
41.2ab

Arginine
89.6a
78.4b
79.9b
80.0b
80.0b
82.2ab
a
b
ab
ab
a
Lysine
82.6
78.2
80.6
81.2
82.4
82.5a
Methionine
85.6ab
72.9c
75.7bc
88.0a
83.6ab
88.2a
a
b
b
b

ab
Threonine
77.5
64.1
64.8
65.3
67.0
74.1ab
Valine
80.5a
73.5b
75.7ab
75.8ab
76.2ab
76.8ab
Values in rows with different superscript letters are significant different (P<0.05)

P

0.001
0.001
0.089
0.091
0.001
0.008
0.004
0.001
0.006
0.014

Table 4.24: Content of nitrogen retention at 8 week-old period (g/bird/day)
Item

Treatment
P
1.04L
0.91L
1.10L
1.10L
1.40L
1.40L
0.46M 0.40M 0.45M 0.55M 0.45M 0.55M
NI
1.45a
1.23b
1.23b
1.23b
1.25b
1.25b
0.001
NF
0.43b
0.52a
0.50a
0.49a
0.41b
0.30c
0.001
NR
1.02a

0.71c
0.73c
0.74c
0.84b
0.95a
0.001
NR/NI, %
70.5b
57.5c
59.2c
60.0c
67.4b
76.3a
0.001
NR/kgW0.75*
1.26a
0.91c
0.92c
0.94c
1.04b
1.17a
0.001
NI: nitrogen intake; NR: nitrogen retention; W0.75: metabolic weight; *: g/kgW0.75; Values
in rows with different superscript letters are significantly different (P<0.05).

The results of Table 4.23 and Table 4.24 showed that the apparent
nutrient, almost amino acid digestibilities, and nitrogen retention contents
of the 1.04L0.46M and 1.40L0.55M treatments were significantly higher
(P<0.05) than those of other treatments. The waste nitrogen content of the
1.40L0.55M treatment was lower than (P<0.05) the 1.04L0.46M

treatment.
At 10 week-old period
19


Table 4.25: Nutrient and amino acid digestibilities (%) of 10-week old birds
Treatment
P
0.98L
0.80L
0.90L
0.90L
1.20L
1.20L
0.43M 0.37M 0.40M 0.50M 0.40M
0.50M
DM
85.5a
72.5d
81.4c
82.0c
82.7bc
84.8ab
0.001
a
d
c
c
bc
OM

88.1
77.4
83.2
83.6
85.4
86.9ab
0.001
EE
88.3
86.3
86.3
86.2
86.8
87.2
0.063
CF
38.5a
26.5b
28.8ab
31.2ab
33.5ab
36.3ab
0.033
NDF
59.8a
35.2c
38.1c
45.7bc
47.4bc
57.6ab

0.001
Arg
90.4a
78.5e
83.2d
85.8c
88.4b
90.0ab
0.001
Lys
89.3a
77.2c
77.6c
80.4b
87.3a
89.5a
0.001
Met
88.4a
74.1c
80.6b
89.7a
82.7b
89.4a
0.001
Thr
80.0a
61.9c
65.3bc
65.8bc 69.0abc

76.1ab
0.001
Val
85.0
72.0
75.3
76.5
80.3
82.8
0.219
Values in rows with different superscript letters are significant different (P<0.05)
Item

Table 4.26: Nitrogen retention (g/bird/day) of birds at 8 weeks of age
Item

Treatment

P

0.98L
0.80L 0.90L
0.90L
1.20L
1.20L
0.43M 0.37M 0.40M 0.50M 0.40M 0.50M
NI
1.49a
1.24b
1.23b

1.24b
1.25b
1.25b
0.01/0.001
NF
0.38b
0.50a
0.35b
0.32bc
0.26cd
0.22d
0.01/0.001
NR
1.11a
0.74e
0.89d
0.92cd
0.99bc
1.02ab
0.02/0.001
NR/NI, %
74.7bc
60.0d
71.8c
74.2bc
79.0ab
82.2a
1.04/0.001
NR/kgW0.75
1.10a

0.74e
0.88d
0.91cd
0.98bc
1.01ab
0.02/0.001
NI: nitrogen intake; NR: nitrogen retention; W0.75: metabolic weight; *: g/kgW0.75; Values
in rows with different superscript letters are significant different (P<0.05)

Table 4.25 and Table 4.26 showed that the apparent nutrient, almost
amino acid digestibilities, and nitrogen retention of the 0.98L0.43M and
1.20L0.50M treatments were the highest values (P<0.05). The content of
excreta nitrogen of the 1.20L0.50M was lower (P<0.05) than the
0.98L0.43M treatment.
4.5 Experiment 5: Evaluation of methods to determine nutrients and
amino acid digestibilities for growing Guinea fowls.
The apparent nutrient and amino acid digestibilities, nitrogen retention
content of total tract digestibility (TD) and caecectomised bird
digestibility (CD) were presented in Table 4.27.

20


Table 4.27: Apparent nutrient digestibilities (%) and nitrogen
retention content (g/bird/day) of TD and CD
Item
DM
OM
EE
CF

NDF
ADF
NR, g/bird/day
NR/NI, %
NR/kgW0.75

Treatment
TD
84.7
85.6
86.9
41.2
55.4
43.8
1.47
82.8
1.18

CD
82.6
83.8
85.8
21.0
38.9
21.8
1.41
80.7
1.13

SEM

P

Difference
TD/CD

0.58
0.55
0.58
2.31
1.92
2.77
0.02
0.72
0.02

0.033
0.045
0.225
0.001
0.001
0.001
0.084
0.078
0.097

2.10
1.80
1.10
20.2

16.5
22.0
-

DM: dry matter; CP: crude protein; EE: extract ether; CF: crude fiber; NDF: neutral detergent fiber;
ADF: acid detergent fiber; NI: nitrogen intake; NR: nitrogen retention; W0.75: metabolic weight; *:
g/kgW0.75; values in rows with different superscript letters are significant different (P<0.05).

Table 4.27 showed that the apparent CF, NDF and ADF digestibilities
of total tract digestibility were higher (P<0.05) than those of
caecectomised bird digestibility due to microbial fermentation in caeca of
the chicken to degrade fiber composition, so the nutrient digestibility
coefficients were increased.
Table 4.28: Apparent amino acid digestibilities (%) of total tract digestibilty
(TD), caecectomised bird digestibility (CD) and ileal digestibility (ID)
Item (%)
Arginine
Isoleucine
Lysine
Methionine
Histidine
Threonine
Valine
Acid glutamic
Tyrosine

TD
87.8a
82.9a
86.3a

87.5a
78.3a
81.9a
78.9a
83.4a
79.1a

Treatment
CD
84.7ab
78.1b
84.0b
82.6b
66.6b
71.8b
71.4b
80.2b
73.1b

ID
84.0b
76.5b
83.6b
82.3b
66.0b
71.2b
70.9b
78.3b
72.7b

SEM

P

0.97
1.04
0.46
1.06
1.24
1.66
1.17
0.62
1.47

0.036
0.003
0.003
0.008
0.001
0.001
0.001
0.001
0.016

Values in rows with different superscript letters are significant different (P<0.05).

Table 4.28 indicated that the apparent digestibility values of 9 amino
acids (isoleucine, lysine, methionine, histidine, threonine, valine, acid
glutamic, tyrosine and prolin) of intact birds were significantly higher
(P<0.05) than those of caecectomised birds, while apparent digestibility

values of other amino acids were similar (P>0.05). Almost apparent
21


amino acid digestibility values of intact birds were significantly higher
(P<0.05) than those of ileal digestibility.
Chapter 4: CONCLUSIONS AND RECOMMENDATIONS
4.1 Conclusions
(1) The nutrient, almost amino acid digestibilities, nitrogen retention
of the treatments with soybeans meal were similar to those of soybean
extraction meal.
(2) The nutrient, almost amino acid digestibilities, nitrogen retention
of the treatments with fish meal were higher than those of catfish byproduct meal.
(3) The diets contained ME levels of 3,100 and 3,200 kcal/kg DM fed
chicken from 5 to 8 weeks and from 9 to 14 weeks of age, respectively,
had significantly higher nutrient intakes, nutrient digestibilities, daily
weight gain, weights of carcasses, breast and thigh and best profits.
(4) The diet containing 1.40% lysine, 0.55% methionine and 17% CP
and the diet containing 1.20% lysine, 0.50% methionine, 15% CP given
to chicken from 5 to 8 weeks and from 9 to 14 weeks of age, respectively,
gave significantly higher daily weight gain, digestibilities of nutrients,
almost amino acids, nitrogen retention and carcass parameters (P<0.05),
better profits and had low excreta nitrogen amount.
(5) The apparent digestibility coefficients of CF, NDF and ADF were
higher (P<0.05) for the intact birds as compared to the caecetomised birds.
Almost amino acid digestibility values obtained from the intact birds were
significantly higher (P<0.05) than ileal digestibility coefficients. The
digestibilities of isoleucine, lysine, methionine, histidine, threonine,
valine, glutamic acid, tyrosine, proline were significantly higher (P<0.05)
for intact birds as compared to caecetomised birds. The amino acid

digestibility values of the caecetomised birds were similar to ileal
digestibility values.
4.2 Recommendations
Using soybean for researching and soybean extraction meal for Guinea
fowl production in order to get higher profits for producers.

22