Impact of farming models on the reproductive performance and egg quality of Vietnamese local chicken breeds: Ho and Dong Tao
ISSN 2588-1299
VJAS 2020; 3(1): 495-503
Vietnam Journal of
Agricultural
Sciences
Impact of Farming Models on the
Reproductive Performance and Egg Quality
of Vietnamese Local Chicken Breeds: Ho
and Dong Tao
Nguyen Van Duy1,2, Hoang Ngoc Mai1, Nguyen Dinh Tien1,
Nguyen Thi Phuong1 & Vu Dinh Ton1
1Faculty of Animal Science, Vietnam National University of Agriculture, Hanoi, 131000,
Vietnam
2Faculty of Veterinary Medicine, University of Liege, Liege 4000, Belgium
Abstract
The study was conducted from October 2016 to December 2017 at
the Experimental Farm, Faculty of Animal Science, Vietnam
National University of Agriculture, with the aim to evaluate the
interaction between farming model types and reproductive
performance of Ho and Dong Tao chickens. The two farming model
types used in this research were (1) the traditional type – backyard
and (2) the ameliorate type – battery cage. Data were collected from
61 Ho hens and 61 Dong Tao hens continuously during 52 laying
weeks. The total number of eggs laid by hens raised in battery cages
averaged 88.47 eggs (for Ho hens) and 94.91 eggs (for Dong Tao
hens), 35-38% higher than the number of eggs laid by hens raised in
a traditional model. The FCR index per 10 eggs laid in battery cages
was significantly lower than that in the back-yard model (P< 0.001).
In both the Ho and Dong Tao breeds, the rate between the number of
embryonated eggs by number of incubated eggs recorded in the
ameliorate model was higher than that recorded in the traditional
model (P< 0.01 for Ho chickens, P< 0.001 for Dong Tao). The weight
of eggs produced by hens raised in battery cages was higher than eggs
laid by free-range hens for both Ho and Dong Tao chickens (P< 0.01).
As such, the reproductive performances and egg quality of both Ho
and Dong Tao breeds were apparently improved when chickens were
raised in battery cages.
Keywords
Received: January 2, 2019
Accepted: June 2, 2019
Battery cage models, farming, indigenous chicken, systems
traditional, Dong Tao chicken, Ho chicken
Correspondence to
Introduction
ORCID
Vu Dinh Ton
Chicken farming in Vietnam has been actively transformed in
recent decades, leading to a significant improvement in meat and egg
495
Impact of Farming Models on the Reproductive Performance and Egg Quality of Vietnamese Local Chicken Breeds
consists of more than 1,000 Dong Tao chicken
households, totaling nearly 10,000 individuals.
Of these, only about 20 farms have a flock size
exceeding 50 hens per household (Dao Thi Hiep,
2013). The population of Ho chickens is very
small, with only 1,404 individuals distributed
among 88 households (Bui Huu Doan & Nguyen
Van Luu, 2006).
performance. Many chicken breeds with high
potential have been implemented in the country.
Chicken farming systems have been also
mechanized and well-constructed with feeding
and drinking systems, light control, and sewage
treatment systems. The influence of farming
models on egg productivity and quality has
previously been published. In detail, caged hens
were shown to produce higher numbers of eggs
in comparison with eggs laid by cage-free hens;
however, a high population density of chickens
raised in cages conclusively caused symptoms of
stress in chickens, possibly leading to reductions
of productivity and disease resistance (Özbey &
Esen, 2007). Chicken genotypes and cage
construction styles were reported to affect egg
weight, yolk weight, and shell weight (P< 0.01)
(Tůmová et al., 2011).
The fact that Ho and Dong Tao chickens
have low reproductive performances while being
raised in a traditional-style farming model
generates an interest in alternative farming
models to enhance egg productivity. For this
reason, this project aims to compare the impact
of a traditional farming model and a battery-cage
system on the reproductive performance and egg
quality of Ho and Dong Tao chickens.
The genetic sources of Vietnamese local
chickens are diverse (Berthouly et al., 2009).
Traditionally, Vietnamese local chicken breeds
were named after their original village or their
typical appearance. In Vietnam, there are about
21 local chicken breeds (MARD, 2016). The
backyard farming model has been implemented
by up to 92% of all chicken farming households
(FAO, 2008), covering 84-85% of farming
households in North Eastern and North Western
Vietnam (Lan Phuong et al., 2015).
Materials and Methods
This research was conducted from October
2016 to December 2017 at the experimental farm
of the Faculty of Animal Science, Vietnam
National University of Agriculture in Hanoi
(Vietnam). Hanoi is located at the latitude of
21°0278’ North and at the longitude of 105°
8432’ East. The weather is sub-tropical, and the
total sunshine time is about 1075.2 hours during
the year. Average monthly temperatures range
from 25.1°C in June to 18.1°C in December.
Average annual humidity is about 76.6%, with
the highest (84%) in March and the lowest (70%)
in December (GSO, 2018). The project contained
two parallel supervisions of Ho and Dong Tao
chickens. In this research, qualitative and
quantitative criteria showing reproductivity and
egg quality were recorded continuously during
the 52 weeks of the laying period. The quality of
the eggs was evaluated in terms of weight,
length, width, and the egg shape index.
Ho and Dong Tao chickens belong to the
most important local chicken breeds in Vietnam
because of their first-class meat quality,
historically regarded as traditional delicacies for
the king (FAO, 2008). Ho chicken originates
from Ho village, Thuan Thanh district, Bac Ninh
province in Northern Vietnam, and features
typical morphological characteristics, including
a massive body size and diversified feather colors
(Nguyen Van Duy et al., 2015). Meanwhile,
Dong Tao chicken originates from Dong Tao
village, Khoai Chau district, Hung Yen province
in Northern Vietnam, and is characterized by
enlarged feet, massive body size, and large
feather-color diversity (Nguyen Van Duy et al.,
2017). In general, Ho and Dong Tao chicken
farming are practised mostly at a small farming
scale and not under the management of local
authorities (Ngo Thi Kim Cuc, 2010; Pham et al.,
2013). The population of Dong Tao chickens
Egg productivity and quality
The criteria of egg productivity were
investigated on 122 Ho and Dong Tao hens (61
hens/breed: 25 hens in a traditional backyard
system and 36 hens in a battery cage model). The
hens were settled in two different farming model
types 15-20 days before laying their first egg.
The traditional farming model was constructed
with a simple chicken house, a soil-made playing
Vietnam Journal of Agricultural Sciences
496
Nguyen Van Duy et al. (2020)
yard for chickens at a density of 01 chicken/m2,
an appropriate design for natural light, was
equipped with rain covers and rice-husks spread
on the floor, and was surrounded by shade trees.
For experimental purposes, in each of flocks, a
cock was maintained to create a “family” at the
rate of 5 hens/1 cock. Alternatively, the second
experimental farming model included a multi-
cell battery cage (cell dimensions: length x width
x height = 40 x 65 x 38cm). The caging blocks
were kept at a distance of 60cm above the
ground. Each cell had a separate door tagged with
a number corresponding to a wing code. The hens
were illuminated for 16 hours per day and the
hens were inseminated artificially every two days
using 0.05mL semen doses.
Average weight was calculated based on the
weight of every egg during the 52 laying weeks.
Each egg’s length and width were measured in
the same way, using electronic sliders with a
±0.01mm accuracy. The shape index was
calculated to be equal to the ratio of the length
and width. All qualified eggs were incubated
using an automatic multi-period electric
incubator with a maximum capacity of 500 eggs.
The embryonic status was checked after 7 days
of incubation by screening under direct white
light. The number of embryonated eggs, new-
born chicks, and deformed new-born chicks were
recorded. The ratio of embryonated eggs/total
incubated eggs and new-born chicks/total
embryonated eggs were calculated in detail.
In both experimental farming models, all the
hens were provided enough drinking water and
fed comfortably with the same diet (Table 1).
Reproductive performance was tested for 52
weeks after the first-egg laying age. Qualified
eggs were collected every day and stored at room
temperature. Among those, eggs collected on
Monday and Tuesday were qualified and
quantified every Wednesday. Good eggs
collected on the other days were hatched.
Abnormal eggs (eg. cracked, ruptured, unshelled,
etc.) were eliminated.
Statistical analysis
The data were analyzed using with SAS 9.1.
the MEANS procedure was used to calculate
means and standard errors (SE). The ANOVA
procedure was used to test the differences
between means of the two farming models with
the significance level set at P< 0.05.
Results
Reproductive traits and egg production
The data on laying percentage of Ho and
Dong Tao chickens is shown in Figure 1.
Generally, the laying rate of Ho and Dong Tao
Eggs were weighed individually using an
electronic balance with a ±0.01g accuracy.
Table 1. Ingredients and nutritive composition of the diet for the laying hens
Ingredients
Corn
Proportion (%)
34.00
Concentrated feed1
Rice bran
16.50
16.00
Paddy
33.00
Premix Mineral –vitamins2
0.50
Nutritive composition of the diet (g kg-1)
Crude protein (CP)
Fat content
142.5
53.46
6.50
Calcium
Phosphorus
5.90
Fiber
42.21
3030.12
Metabolizable energy (kcal kg-1)
Note: 1 Protein-rich feed, crude protein 45%; 2 vitamin A: 3 000 000 UI kg-1, vitamin D3: 30 000 UI kg-1, vitamin E: 100 mg kg-1
497
Impact of Farming Models on the Reproductive Performance and Egg Quality of Vietnamese Local Chicken Breeds
chickens is shown in Figure 1. Generally, the
laying rate of Ho and Dong Tao chickens was
low. The laying rate of Ho hens was lower than
that of Dong Tao hens. The laying rate of these
two breeds varied by about 20%.
analyses in Tables 2 and 3 revealed an apparent
disparity in feed consumption for hens raised in
battery cages compared to hens raised in a
traditional style, with the domination belonging
to the earlier group.
The influence of the farming model type on
the reproductive performance of Ho and Dong
Tao chickens is analyzed in Tables 2 and 3. In
both experimental breeds, almost all the
remarkable indicators of egg productivity
showed considerable relationships with the
farming model types.
The egg hatchability criteria also showed a
tight correlation with the farming model types.
Concretely, the number of qualified eggs for
incubation, number of embryonated eggs,
embryonated eggs/incubated eggs ratio, and
hatched eggs/incubated eggs ratio were
significantly correlated with the farming model
types in both Ho and Dong Tao breeds (P< 0.01;
P< 0.001) (Tables 4 and 5). The embryonated
eggs/incubated eggs ratio of eggs laid by hens
in a ameliorate farming model type was higher
than those of the hens raised in traditional type
by about 13% for Ho chickens and 18% for
Dong Tao.
The production yield during the 52 laying
weeks of Ho hens raised in battery cages was
88.47 eggs on average, which was 35% higher
than the number of eggs laid by Ho hens freely
released in a traditional farming model (P< 0.05,
Table 2). Meanwhile, egg productivity of Dong
Tao hens raised in battery cages during the 52
laying weeks was 94.91 eggs on average, which
was 38% higher than the number of eggs laid by
hens raised in a conventional model (P< 0.05,
Table 3). The amount of feed consumed by the
hens per day, the feed consumption for 52 weeks,
the feed conversion ratio to produce 10 eggs, and
the FCR were significantly correlated with the
flock type in both Ho and Dong Tao breeds. Data
Similarly,
the
ratio
of
hatched
eggs/incubated eggs was very different between
the two farming model types with the dominance
belonging to the hens raised in battery cages (P<
0.001). On the contrary, there were no
differences between the two farming model types
in the hatched eggs/fertile eggs ratio and chick
malformation ratio for the two chicken breeds.
Figure 1. Laying percentage of Ho and Dong Tao chickens in the battery cage model by weeks
Vietnam Journal of Agricultural Sciences
498
Nguyen Van Duy et al. (2020)
Table 2. Laying performance and feed consumption of Ho hens by farming model types
Battery cage model
Criteria
Traditional model
P
n1
Means ± SE
n2
Means ± SE
Total number of eggs in 52 weeks of
laying (eggs)
36
88.47 ± 3.87
5
65.52 ± 8.23
*
Feed consumption per hen per day (g)
36
36
105.97 ± 0.71
38.57 ± 0.25
5
5
97.32 ± 1.84
35.42 ± 0.67
***
***
Feed consumption per hen in 52 weeks
of laying (kg)
Feed conversion ratio (FCR/10 eggs)
(kg)
36
4.36 ± 0.03
5
5.40 ± 0.10
***
Note: (n1): number of hens; (n2): number of blocks *** P<0.001; * P< 0.05; Means ± SE: Mean ± Standard Error
Table 3. Laying performance and feed consumption of Dong Tao hens by farming model types
Battery cage model
Traditional model
Criteria
P
n1
Means ± SE
n2
Means ± SE
Total number of eggs in 52 weeks of
laying (eggs)
36
36
36
94.91 ± 4.40
5
68.92 ± 8.61
96.24 ± 2.01
34.80 ± 0.76
*
Feed consumption per hen per day (g)
105.79 ± 0.60
38.51 ± 0.22
5
5
***
***
Feed consumption per hen in 52 weeks
of laying (kg)
Feed conversion ratio (FCR/10 eggs)
(kg)
36
4.06 ± 0.02
5
4.57 ± 0.09
***
Note: (n1): number of hens; (n2): number of blocks; *** P< 0.001; * P< 0.05; Means ± SE: Mean ± Standard Error
Table 4. Fertilizing ability of Ho chickens by farming model types
Battery cage model
Traditional model
Means ± SE
Criteria
n
Means ± SE
27.15 ± 2.10
24.04 ± 1.89
n
Incubated eggs (eggs)
46
46
61
61
12.42 ± 0.28
8.93 ± 0.25
Embryonated eggs (eggs)
Embryonated eggs/incubated eggs ratio
(%)
46
46
88.27 ± 0.82
75.09 ± 1.38
61
61
75.52 ± 1.82
61.78 ± 1.41
Hatched eggs/incubated eggs ratio (%)
Hatched eggs/embryonated eggs ratio
(%)
46
46
85.19 ± 1.47
1.74 ± 3.19
61
61
85.95 ± 1.20
1.27 ± 0.58
Chick malformation ratio (%)
Note: (n): number of incubation batches; *** P< 0.001; ** P< 0.01; NS: P> 0.05; Means ± SE: Mean ± Standard Error
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Impact of Farming Models on the Reproductive Performance and Egg Quality of Vietnamese Local Chicken Breeds
Table 5. Fertilizing ability of Dong Tao chickens by farming model types
Battery cage model
Means ± SE
Traditional model
Means ± SE
Criteria
n
n
Incubated eggs (eggs)
47
47
47
36.36 ± 1.43
32.10 ± 1.26
35
35
14.08 ± 1.41
9.85 ± 0.99
Embryonated eggs (eggs)
Embryonated eggs/incubated
eggs ratio (%)
88.70 ± 0.90
75.73 ± 1.24
35
35
70.55 ± 1.42
58.87 ± 2.52
Hatched eggs/incubated eggs
ratio (%)
47
47
Hatched eggs/embryonated eggs
ratio (%)
85.46 ± 1.21
1.33 ± 0.60
35
35
83.52 ± 3.32
1.78 ± 0.89
Chick malformation ratio (%)
47
Note: (n): number of incubation batches; *** P< 0.001; NS: P> 0.05; Means ± SE: Mean ± Standard Error
Table 6. Weight and external egg quality measurements of Ho hens by farming model type
Battery cage model
(n = 1080)
Traditional model
(n = 586)
Criteria
P
Means ± SE
51.43 ± 0.17
52.47 ± 0.09
41.63 ± 0.05
1.26 ± 0.35
Means ± SE
50.37 ± 0.18
52.95 ± 0.10
41.65 ± 0.07
1.27 ± 0.15
Weight (g)
Length (mm)
Width (mm)
Shape index
**
NS
NS
NS
Note: (n): number of specimens; ** P <0.01; NS: P >0.05; Means ± SE: Mean ± Standard Error
Table 7. Weight and external egg quality measurements of Dong Tao hens by farming model type
Battery cage model
(n = 1723)
Traditional model
(n = 1106)
Criteria
P-value
Means ± SE
51.69 ± 0.19
53.81 ± 0.11
40.79 ± 0.22
1.32 ± 0.38
Means ± SE
50.55 ± 0.14
52.81 ± 0.08
41.39 ± 0.06
1.28 ± 0.11
Weight (g)
Length (mm)
Width (mm)
Shape index
**
***
***
***
Note: (n): number of specimens; ** P< 0.01; *** P< 0.001; Means ± SE: Mean ± Standard Error
than the weight of eggs produced by hens raised
in the conventional farming model (51.43g and
Weight and external egg quality
The indicators of weight and external egg
quality measurements are presented in Table 6
(for Ho breed) and Table 7 (for Dong Tao breed).
For Ho chickens, the weight of eggs produced by
hens raised in battery cages was slightly higher
50.37g, respectively, P< 0.01). Other criteria
about egg size (length, width, and shape index)
showed no significant correlations with the
farming model types (P> 0.05). For Dong Tao
Vietnam Journal of Agricultural Sciences
500
Nguyen Van Duy et al. (2020)
chickens, the difference of egg weights produced
by hens raised in the two models was statistically
meaningful (P< 0.01). The egg size criteria
revealed a significant correlation with the farming
model types (P< 0.001). Overall, the size of eggs
laid by Dong Tao hens raised in a traditional flock
were slightly higher than the size of eggs laid by
Dong Tao hens raised in cages (Table 7).
influential factor on changing physiological
behaviors of laying hens (Özbey & Esen, 2007).
According to our data, feed consumption for
hens raised in battery cages was relatively higher
than those raised in a traditional production type.
The narrow space possibly stimulated the eating
demand of the chickens. Nonetheless, the egg
reproductive performance of chickens raised in
battery cages was significantly higher than that
of chickens raised on the ground, resulting in a
more effective feed conversion ratio per 10
eggs recorded.
Discussion
Reproductive traits and egg production
Poultry reproductive performance is strongly
regulated by genetic factors (Dottavio et al.,
2001). In this study, the egg productivity of Ho
and Dong Tao chickens raised in traditional and
battery cage models were recorded as 65.52-
88.47 eggs/hen/laying year and 68.92-94.91
eggs/hens/laying year, respectively. Egg
production depended on the farming model type.
Compared to other studies, the laying
performances of these two breeds were higher
than that of fighting chickens (54.04
eggs/hen/year) and the Mia breed (55-60
eggs/hen/year) (MARD, 2016). However, the
egg productivities of Ho and Dong Tao chickens
were intensely lower than that of Ri chickens
(123 eggs/hen/year) (FAO, 2008). The
reproductive cycles of Ho and Dong Tao
chickens usually last 2-3 weeks, with the
frequency of one egg per 2-3 days. After the
laying period, hens entered an incubation stage
lasting about 3 weeks. Recently, small automatic
incubators (500 eggs per plant) have been
popularly used in farming households for egg
incubation. This has contributed to an increase in
egg production by decreasing the incubating
period. In some cases, farmers use female turkeys
for incubating. The purpose of these practices is
to increase the hatching rates, and to also push
the next reproductive cycle of the hens. However,
the habit of hatching without eggs in Ho and
Dong Tao hens is mostly unavoidable.
The rates of embryonated eggs in the Ho and
Dong Tao experimental populations in the
traditional model were considerably lower than
that of other local chicken breeds. In detail, this
rate in Ho and Dong Tao chickens was 75.52%
and 70.55%, respectively, compared to this
indicator in multi-toe chickens (80.45%) (
Nguyen Hoang Thinh et al., 2017) and in
H’mong chickens (89.56%) (Duong Thi Anh
Dao & Vu Thi Cuc, 2011). The massive bodies
of Ho and Dong Tao chickens, which causes
difficulties in mating, elucidates this low fertile.
Besides, semen quality of Ho and Dong Tao
cocks is not high (Do Thi Hue et al., 2017).
Weight and external egg quality parameters
This study showed that there was a
significant difference in egg weight of both
chicken breeds by farming model types. This
result encounters a conflict with a previous
report, which stated that eggs laid by chickens
raised on the ground were heavier than those laid
by chickens raised in battery cages (Özbey &
Esen, 2007). However, a significant correlation
between farming models and egg weight was also
recorded in another research paper which showed
that the eggs from cages were heavier than those
from the litter (Tůmová et al., 2011).
Egg weight is an indicator influenced by
chicken body weight and genetic factors (Moula
et al., 2009). In this study, the weight of eggs
produced by Ho and Dong Tao chickens raised in
two experimental farming model types were
50.37-51.43g and 50.55-51.69g, respectively.
Meanwhile, the egg weight of H’mong chickens
and multi-toe chickens were 38.10g (Nguyen Thi
Phuong et al., 2017) and 39.70g ( Nguyen Hoang
Our results show that egg productivity of
hens raised in battery cages was significantly
higher than those raised in a traditional farming
model type. This observation is compatible with
the results of a previous study, in which the
authors mentioned that stress might be an
501
Impact of Farming Models on the Reproductive Performance and Egg Quality of Vietnamese Local Chicken Breeds
provides evidence of gene flow from wild to domestic
populations. BioMed Central Genetics. 10: 1-8.
Thinh et al., 2017) on average, respectively. It
can be seen that the egg weight of Ho and Dong
Tao chickens was considerably higher than those
of other local breeds. In addition, the egg shape
index of Ho and Dong Tao eggs were 1.26-1.27
and 1.28-1.32, respectively. According to our
Bui Huu Doan & Nguyen Van Luu (2006). A survey on
distribution, conformation, growth and productivity of
Ho chicken. Vietnam Journal of Agricultural Sciences.
4: 95-99.
Do Thi Hue, Nguyen Van Duy, Nguyen Thi Xuan, Do Duc
results, the egg shape index of chickens raised in
battery cages was higher than those raised in the
traditional model. This conclusion was also
reported in the literature (Özbey & Esen, 2007)
with the shape indices of eggs being 77.65% for
eggs from cages and 75.39% for eggs from the
ground.
Luc, Le Thi Tham, Dang Vu Binh & Vu Dinh Ton
(2017). Semen quality and some factors affecting the
semen quality of Dong Tao chicken. Vietnam Journal
of Agricultural Sciences. 5: 598-604 (in Vietnamese).
Dao Thi Hiep (2013). Production efficiency and
consumption of some local chicken breeds: the case
study of Ho and Dong Tao chickens: Hanoi University
of Agricultural.
Dottavio A. M., Canet Z. E., Alvarez M., Creixell B., Di
Masso R. J. & Font M. T. (2001). Productive traits in
Conclusions
hybrid
genotype. Archivos Latinoamericanos de Producción
Animal. (2). Retrieved from
hens
with
Fayoumi
maternal
The reproductive performance of Ho and
Dong Tao chickens raised in battery cages
showed considerable differences compared to
chickens raised in a traditional farming model.
The feed conversion ratio to produce 10 eggs for
hens raised in the battery cages model was
significantly lower than those raised in the
conventional farming model. The weight of eggs
produced by Ho and Dong Tao hens raised in
battery cages were better compared to the
traditional way.
9
9646 on July 2, 2019.
Duong Thi Anh Dao & Vu Thi Cuc (2011). Studing on
some growing and reproductive characteristics of
H'mong chickens reared under scavenging and
semidustrial conditions in Thuan Chau - Son La.
Journal of Animal Husbandry Sciences and Technics.
12:14-20.
GSO (2018). Statistical handbook of Hanoi; Statistical
Publishing House.
FAO (2008). Poultry systems in Vietnam Prepared by Duc
N. V. & Long T. GCP/RAS/228/GER working paper
Our recordings and analyses in this study
result in an implication that egg hatchability of
these two valuable local chicken breeds can be
considerably improved when the ameliorate
farming model type was applied. However, the
concern of animal welfare should remain when
considering farming model types in real scale.
No.
4.
Rome.
Retrieved
from
http://www.fao.org/3/al693e/al693e00.pdf on May 25,
2019.
MARD (2016). Atlas of livestock breeds in Vietnam,
Ministry of Agriculture and Rural Development (in
Vietnamese).
Moula N., Antoine-Moussiaux N., Farnir F & Leroy P.
(2009). Comparison of egg composition and
conservation ability in two Belgian local breeds and
one commercial strain. International Journal of Poultry
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Acknowledgements
We would like to express our highest
appreciation for the Académie de Recherche et
d’Enseignement supérieur Commission de la
Coopération au Développement (ARES – CCD)
(Belgium) for its financial support to complete
this research project.
Ngo Thi Kim Cuc (2010). Vietnamese local chicken
breeds: Genetic diversity and prioritizing breeds for
conservation. PhD Thesis. Georg-August Universität.
Nguyen Hoang Thinh, Pham Kim Dang, Vu Thi Thuy
Hang, Hoang Anh Tuan & Bui Huu Doan (2017).
Phenotypical
Characteristics
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