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EFFECT OF MOISTURE LOSS ON THE HATCHABILITY
OF CHICKEN, DUCK AND QUAIL EGGS
A THESIS BY
MD. TAREQ HOSSAIN
Examination Roll No. 10 AHPS. JJ 20 M Registration No. 31413
Semester: January – June 2011 Session: 2004-2005
MASTER OF SCIENCE (M S) IN
POULTRY SCIENCE
DEPARTMENT OF POULTRY SCIENCE
BANGLADESH AGRICULTURAL UNIVERSITY MYMENSINGH
MAY 2011
2
EFFECT OF MOISTURE LOSS ON THE HATCHABILITY
OF CHICKEN, DUCK AND QUAIL EGGS
A THESIS BY
MD. TAREQ HOSSAIN Examination Roll No. 10 AHPS. JJ 20 M
Registration No. 31413 Semester: January – June 2011
Session: 2004-2005
Submitted to the Department of Poultry Science, Bangladesh Agricultural University, Mymensingh in partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE (M S) IN
POULTRY SCIENCE
DEPARTMENT OF POULTRY SCIENCE
BANGLADESH AGRICULTURAL UNIVERSITY MYMENSINGH
MAY 2011
3
EFFECT OF MOISTURE LOSS ON THE HATCHABILITY OF
CHICKEN, DUCK AND QUAIL EGGS
A THESIS
BY
MD. TAREQ HOSSAIN Examination Roll No. 10 AHPS JJ-20 M
Semester: January-June 2010
Registration No.: 31413
Session: 2004-2005
Approved as to style and content by
…………………………………………… (Dr. M. A. R. Howlider)
Supervisor
………………………………………………………. (Dr. Shubash Chandra Das)
Co-supervisor
…………………………………………………………………………… (Dr. Md. Shawkat Ali)
Chairman, Defence Committee And
Head, Department of Poultry Science Bangladesh Agricultural University
Mymensingh
MAY 2011
4
ACKNOWLEDGEMENTS
All praises are due to the Almighty Allah who has enables the author to pursue his
higher education in Poultry Science and to complete the thesis for the degree of
Master of Science (M S) in Poultry Science.
It is a great pleasure of the author to express his sincere appreciation and heartfelt
thanks to his honorable supervisor prof. Dr. M. A. R. Howlider, Department of
Poultry Science, Bangladesh Agricultural University, Mymensingh for his scholastic
guidance, responsible supervision, valuable suggestions, constructive criticism and
affectionate feeling at all stages of the study period of research work and preparation
of this thesis.
The author wishes to extend his sincere appreciation and best regards to his Co-
supervisor, Associate Prof. Dr. Shubash Chandra Das, Department of Poultry
Science, Bangladesh Agricultural University, Mymensingh for his generous co-
operation, creative advice, and various suggestions during the entire period of the
research work and in preparing this thesis.
The author sincerely express his heartfelt respect, deepest gratitude and thanks to his
respectful teacher Associate prof. Dr. Shawkat Ali, Head, Department of Poultry
Science, Bangladesh Agricultural University, Mymensingh for his helpful instruction,
inspiration, positive criticism, affectionate encouragement and helpful comments.
The author would like to extend his heartfelt appreciation to all teachers of the
Department of Poultry Science, Bangladesh Agricultural University, Mymensingh
for their constant and continuous encouragement and valuable advice to complete this
research work and completion of the thesis.
The author expresses his heartfelt respect and profound thanks to Assit. prof. Dr.
Tahera Yeasmin, Department of Dairy and Poultry Science, Hajee Md. Danesh
5
Science and Technology University, Dinajpur for her kind co-operation in his
research.
The author appreciates the assistance rendered by the staff of the Department of
Poultry Science, Bangladesh Agricultural University, Mymensingh who have helped
him during the period of the study.
The author would like to acknowledge his heartiest gratitude to his beloved mother
Mst. Purnima Khatun, father Md. Tabibar Rahman Pk., brother and sister for their
never ending prayer, affection, support, sacrifice, inspiration, encouragement and
continuous blessings in the long process of building his academic career which can
never be repaid.
The author admires his beloved friend Yousuf, Panir, Delwar, Dipok, Soton, Jewel,
Asad and Nebash for their kind co-operation to carry out the research work.
Last of all, all credit belongs to Almighty Allah.
The author
6
ABSTRACT
A total of 480 eggs; 120 from Rhode Island Red (RIR) chicken, 60 from
Zending duck and 300 from Japanese quail were collected and set in the same
incubator with 3 replications to compare hatchability results among the species.
Moisture loss percentage was highest (P<0.01) in quail eggs (16.19%),
intermediate in chicken eggs (7.76%) and lowest in duck eggs (7.24%). Among
3 genotypes, at all (0, 7 and 14 days) ages, eggs weight was highest (p<0.01) in
Zending duck (60.50g), intermediate in RIR chicken (59.18g) and lowest in
quail (9.55g). Egg weight loss at 7 and 14 days of incubation were highest in
quail, intermediate in chicken and lowest in duck. There was no appreciable
differences of hatchability on set eggs and fertile eggs among species (p>0.05).
Apparently, the hatchability on fertile eggs was similar and higher in chicken
(58.3%) and quail (58.9%) and slightly lower in duck (53.7%). However,
hatchability on set eggs was highest in quail (58.3%) intermediate in chicken
(43.3%) and lowest in duck (40.7%). Chick weight at hatchings was highest
(p<0.01) in duck (37.55g), intermediate in chicken (34.56g) and lowest in quail
(5.61g). Chick weight as per cent of egg weight was found highest (p<0.01) in
duck (62.07%), intermediate in chicken (58.40%) and lowest in quail (54.24%).
There were some relations among the different hatchability results depending on
species. There were marked variations in moisture effect among the species. It
was clear that hatchability not only affected by species but moisture loss also
played an important role on hatchability. It was concluded that under similar
environment, hatchability on fertile eggs were similar and higher in quail and
chicken and lower in duck. But hatchability on set eggs was highest in quail,
intermediate in chicken and lowest in duck. It imply that some losses of
moisture with various level may be necessary to enhance egg hatchability is
required to support hatching results in different species of poultry.
7
CONTENTS
CHAPTER TITLE PAGE ACKNOWLEDGEMENTS i ABSTRACT iii CONTENTS iv-v LIST OF TABLES Vi LIST OF FIGURES Vii SYMBOLS ANDABBREVIATIONS viii
1 INTRODUCTION 1-4
2 REVIEW OF LITERATURE 5-12
2.1 Effects of management and environment on hatchability
5-6
2.2 Effect of egg weight on fertility and hatchability 7-9
2.3 Effect of Relative Humidity on hatchability 9-10
2.4 Effect of age on hatchability 11
2.5 Effect of egg weight on chick weight 12
3 MATERIALS AND METHODS 13-17 3.1 Collection and storing of hatching eggs 13
3.2 Selection and care of hatching eggs 13
3.3 Cleaning and Disinfection of Hatching Eggs 13 3.4 Disinfection and fumigation 13
3.5 Eggs traying in setter 14
3.6 Turning of eggs 14
3.7 Control of temperature 14
3.8 Control of humidity 15
3.9 Weighing of eggs 15
3.10 Transfer of eggs 15 3.11 Hatching records 15
8
CONTENTS (continued)
5
CHAPTER TITLE PAGE 3.11.1 Candling of eggs 15 3.11.2 Fertility records 15 3.11.3 Records of baby chicks hatched and
separation of normal and abnormal
16
3.11.4 Day old chick weight 16 3.11.5 Record keeping and data transformation 16 3.11.5.1 Calculation of moisture loss 16 3.11.5.2 Calculation of hatchability 16 3.11.5.3 Calculation of chick weight as per cent of
egg weight
17
3.12 Statistical analysis 17
4 RESULTS AND DISCUSSION 18-27
4.1 Egg weight loss (g) 18
4.2 Moisture loss (%) 23
4.3 Hatchability (%) 23
4.4 Weight of chicks at hatching 25
4.5 Chick weight as per cent of egg weight 25
5 SUMMARY AND CONCLUSION 26-28
6 REFERENCES 29-38
9
LIST OF TABLES
TABLE TITLE PAGE
1 Egg weight and moisture loss results of chicken, duck and
quail eggs
24
2 Hatchability results of chicken, duck and quail eggs 24
3 Day old chick weight results of chicken, duck and quail eggs
24
10
LIST OF FIGURES
FIGURE TITLE PAGE 1 Relation of egg weight with incubation period in
different poultry species
19
2 Relation of egg moisture loss% with incubation period in
different poultry species.
20
3 Relation of egg weight and chick weight in different
studied poultry species
21
4 Relation of egg weight and egg moisture loss% during
incubation period in the different experimental poultry
species
22
11
SYMBOLS ANDABBREVIATIONS
% “ * ** @ < > ANOVA Cft/m Contd. CRD Dr. e.g. et al. etc. g HD Hrs. i.e. J/W Kg Km LSD Ltd. M3 No. NS oF P Prof. RH SD Sft
: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : :
Percentage Inch Significant at 5 % level f probability Significant t l9o level f probability At the rate of Less than Greater than Analysis of Variance Cubic feet per minute Continued Completely R randomized design Doctor Example given Associates Et cetera Gram Hatching date hours That is James way Kilogram Kilometer Least Significant Difference Limited Cubic meter Number Non significant Degree Fahrenheit Probability Professor Relative humidity Setting date Square feet
12
CHAPTER 1
INTRODUCTION
The hatchery man is interested in number of saleable chicks out of the
egg purchased. Recently, demand for quality chicks is very high
throughout the year. At present hatchery industry can not meet the
increasing demand. Therefore, the year round availability of quality
chicks at a reasonable price to be encouraged in commercial
hatcheries. The principal objective of the commercial hatchery is to
secure the maximum number of quality day old chicks out of the eggs
set for hatching.
Two major concerns are the fertility of eggs and the hatchability of
careless fertile eggs. The incubation procedures including proper
following of the requirements of temperature, humidity, turning of
eggs are important for maintenance and improvement of hatching of
eggs. In order to obtain a sufficient number of eggs to fill an incubator,
eggs are usually accumulated under storage for 3 to 10 days before
incubation (Kuurman et al., 2002). In order to prevent embryonic
development during the storage period, eggs must be stored at low
temperature. For eggs stored for less than 4 days, egg room
temperature should be 200C-250C, whereas for those stored 4-7 days,
temperature should be maintained between 160C and 170C, and for
eggs stored for more than 7 days, temperature should be lowered to
100C-120C (Meijerhof, 1992). Storage causes egg water loss by
evaporation, the rate which is influenced by storage temperature and
13
relative humidity. Studies report that long storage periods are
detrimental to both table and hatching egg quality (Samli et al., 2005;
Scott et al., 2000; Walsh et al., 1995). One of the key points of
incubation is the humidity control of incubators to allow a successful
incubation performance. Water accounts for 68.25% of total eggs mass
before incubation (Martin and Arnold, 1991). The amount of moisture
lost from the eggs during incubation can affect hatchability (Lundy,
1969) and chick weight (Burton and Tullett, 1985). During incubation,
a certain amount of water must be around the embryos to protect them
from drying out at an early stage of development (Yoshizaki and
Saito, 2002). Conversely, at a late stage of development, the drying of
embryos to some extent is necessary to initiate air breathing (Bainter
and Fehér, 1974).
An increase in the number of storage days elevates embryo mortality
rate during storage and incubation, and thereby increases the
probability of failure to hatch (Whitehead et al., 1985; Yoo and
Wientjes, 1991; Scott and Mackenzie, 1993). Some researchers
reported hatchability reductions of as much as 5% per day after 7 days
of storage (Mayes and Takeballi, 1984). According to egg weight,
significant correlations were found between hatchability and egg
weight (Baspinar et al., 1997). Egg fertility and hatchability of fertile
eggs were correlated with egg weight (-0.15 and 0.60 respectively)
(Senapati, et al., 1996). Extensive trial at the Missouri Agricultural
Experimental Station showed that high humidity where hatching eggs
were held increased hatchability because high humidity tends to
14
prevent evaporation and the enlargement of air cell (Funk and
Forward, 1944). It was reported that egg storage prior to incubation
can have both detrimental and beneficial effects (Brake et al., 1993).
Excessively long storage before incubation reduces hatchability
(Braker, 1964). On the other hand, other studies reported that eggs
stored for a few days presented higher hatchability than those set in an
incubator immediately after lay. During storage, hatchability is
increased by the length of the storage period, temperature, humidity,
gaseous exchange and the orientation of the eggs (Megjerhof, 1992).
The rate of water loss from eggs during incubation can be regulated
through changes in incubator relative humidity (Peebles et al., 1987;
Tullett, 1990). However, if water loss is too low or too high, embryo
development might be affected (Rahn and Ar, 1974), which
consequently affects the egg hatchability. Water loss is a normal
physiological phenomena observed during incubation, and previous
reports suggest an approximate 12 to 14% of water loss by broiler and
turkey eggs (Meir et al., 1984; Meir and Ar, 2008). However, they did
not compare moisture loss among the species during incubation period
and its consequence on hatchability. Until now, research findings on
the effect of moisture loss from the eggs and its effects on hatchability
is scantly in literature. Therefore, it is worthy to investigate the loss of
moisture during collection, storage and incubation of eggs in different
species for optimizing fertility and hatchability results. Thus the
current study was designed to assess the moisture loss at various
15
stages of incubation and there effect on hatchability in chicken, duck
and quail eggs.
The research objectives were:
1. To comparison of egg hatchability and associated traits among
chicken, duck and quail eggs.
2. To find out the relationships of moisture loss with hatchability in 3
different species of poultry.
16
CHAPTER 2
REVIEW OF LITERATURE
Many works have done to know the performance of different broiler
strains in different parts of the world. Fertility and Hatchability have
been reported to be influenced by genetic, moisture loss from egg,
relative humidity, physiological, social and environmental factors,
male-female ratio, age, nutritional status, preferential mating, lighting,
sperm quality, rate of egg production and quality of eggs etc. (Warren,
1953 and Jull, 1970). This review compiled information on
consequence of moisture loss on hatchability of chicken, duck and
quail eggs.
2.1 Effects of management and environment on hatchability Krisnappa et al. (1992) recorded the performance of broiler breeder
dams they concluded that feed restrictions during growth 17 to 22
weeks old significantly reduced body weight with increased age at
sexual mortality and also increased fertility and hatchability.
Spralt and Leeson (1987) mentioned that excess energy intake was
predominantly stored as fat which gradually increased body weight
and markedly reduced fertility and hatchability. They also reported
17
that excessive body weight in broiler breeder female was negatively
correlated with fertility and hatchability.
Serbul (1984) studied the effect of position of muscovy eggs in the
artificial incubation. He reported that the hatchability of the egg set
were 53.2%, l0% and 10% in the horizontal, vertical or at 450
respectively. The degree of fertility and hatchability directly depends
on keeping conditions of layer birds. Other factors like egg size,
weight, (Kalita, 1994) storage time of eggs, temperature and humidity
stress.
Card and Neshim (1978) stated that hatchability, embryonic mortality,
dead-in-shell, normal chick hatched out depends on storage of egg,
position' angle of setting, humidity, temperature and 02 and CO2 ratio.
Robertson (1961), Orszagh and Micek (1961), Bohren et al. (1961)
and Farnsworth (1962) demonstrated that care of hatching eggs,
humidity, turning, incubation temperature and hatching time play
important roles in determining hatchability during incubation.
Jull (1952) stated that the proper management of breeding stock is of
great importance in securing good fertility. The number of females
per male, social dominance, light and sperm quality plays a significant
role in the process of fertilization (Byerly and Godfrey, 1937;
Champion and Rood, 1958; Mccartneys and Shaffner, 1950 and
Parker and Spadden, 1949).
Warren (1953) and Hutt (1938) stated that hatchability of fertile eggs
is influenced by both genetic and environmental factors. Lethal and
semi lethal genes affect the hatchability of eggs. Among the
18
environmental factors, storage, temperature, care and age of hatching
eggs, quality of the eggs, age of the birds, season, nutrition, pre
incubation warming, pre-incubation humidity etc. affect hatchability.
2.2 Effect of egg weight on fertility and hatchability
Baspinar et al. (1997) studied the effect of egg weight on hatchability
in Japanese quail eggs. According to egg weight, significant
correlations were found between hatchability and egg weight. The
regression of hatchability (y) on egg weight (x) was y: 454.A -25.4x,
respectively. The R2 value indicates that 82.4% of the variability in
hatchability was explained by variation in egg weight.
Senapati et al. (1996) recorded the egg weight fertility and
hatchability of 918 quail eggs. Egg fertility and hatchability of fertile
eggs were correlated with egg weight (-0.15 and 0.60 respectively).
Salahuddin et al. (1995) worked on 1463 eggs from deshi chicken
were utilized to study of egg weight on fertility and hatchability. The
average fertility and hatchability was found 80.7% and, 77.73%
respectively. Fertility increased with the increase of egg weight and
their correlation was found significant (P<0.01). Hatchability
increased with the increase of egg weight and significant positive
correlation(r= 0.67) was found between egg weight and hatchability
(P<0.01). Dead in germ and dead in shell were found to be negative
correlation with egg weight (-0.040 and -0.33). Chick weight was
found to be positively correlated with egg weight (r=0.56). Larger egg
size resulted better fertility and hatchability and reduced dead in
germs and dead in shells in free range deshi chicken.
19
Mitrovic et al. (1995) classified eggs into 5 groups according to their
weight; 5l-54, 55-58, 59-62, 63-66 and 67-70g.
The 2nd and 3rd groups gave the best results for egg fertility (90.32
and 91.35 respectively) and hatchability of fertile eggs (92.29 and
96.95% respectively). Poorest results were for the heaviest eggs
(83.87% fertility and 73.08% hatchability).
Kaygisiz et al. (1994) worked on 2265 eggs in 5 weight groups were
stored for 1-7 days prior to incubation. Storage time and egg weight
did not significant affect egg fertility. The hatchability of fertile eggs
stored for 1, 2, 3, 4, 5, 6 or 7 days was 84, 70, 69, 74, 77, 90 and 54%
respectively. The decline in hatchability after day 6 was highly
significant. For eggs weighing, 52.0, 52.0-55.9, 56-59.9, 60-63.9 and
>= 63.0 g, hatchability of fertile egg were 74.4, 81.2, 74.2, 70.2 and
64.3%, the differences of the last group from other groups being
highly significant.
Bhuvnesh et al. (1994) worked on White Rock X Red Cornish
broilers at 1200m altitude. He found small and medium size eggs had
higher hatchability compared with large size eggs; this was found for
both total and fertile eggs set. However, chicks hatched from large
eggs (61-65g) had higher weight at hatching.
Kalita (1994) studied on 1800 eggs from 850 WLH and 564 RIR
fowls. For both breeds hatchability was higher for medium size eggs
(51-55g) than small (45-50g) and large (56-60g) eggs. Hatchability
was higher in RIR than in WLH fowls. Asusquo et al. (1993)
collected eggs from 1600 hens in their 1st to 6th month lay were
20
analyzed. Egg weight (37.5-56g) had no significant effect on egg
fertility (81.22-55.07%), but the hatchability of small eggs was lower
than that of medium and large size eggs (72.12 vs. 99.24 and 94.79,
p<0.05 respectively) Month of lay had no significant effect on egg
fertility and hatchability.
Sergeeva (1984) studied the effect of egg weight on hatchability. He
reported 92.10, 93.80 and 88.60% hatchability of the fertile eggs
weighing 50-56.9, 57-64.9 and 65-72.99g respectively. Provakaran et
al. (1984) noted influence of egg size of WLH on hatchability. He had
76.66 and 67.42% hatchability for large eggs (56-60g), 73.97 and
62.77% for medium eggs (51-55g) and 71. 33 and 61.20% for small
eggs (46-50g) on fertile and egg set.
Among et al. (1984) collected, l327 large, medium and small eggs
from 5 White Leghorn for incubation, weighing 54-56, 49-51 and 44-
46g respectively. For large, medium and small eggs respectively, egg
fertility were 86.99,89.68 and 84.87% and hatchability of fertile eggs
92.03, 89.81 and 86-71% b<0.05).
2.3 Effect of relative humidity on hatchability
Romao et al. (2009) studied effect of relative humidity during
incubation of Japanese quail eggs on hatchability, egg weight loss,
hatch weight, and embryo mortality. A total of 150 Japanese quails
(Coturnix japonica) were used for egg collections. The eggs were
divided into three experimental groups: low humidity group
(36.05±6.06% RH; n=100), intermediate humidity group
(52.25±4.99% RH; n=100) and high humidity group (76.50±4.44%
21
RH; n=100). Each group of eggs was incubated in an individual
incubator, according to its experimental relative humidity during
incubation. Incubation process was done by automatic incubators with
temperature of 37.5°C, and egg turning every 30 minutes. At the 15th
day of incubation (360h) egg turning was stopped and the eggs were
transferred to the hatcher that maintained the same temperature and
relative humidity until hatch. All eggs were weighted on 1st, 5th, 10th,
and 15th day of incubation and quail chicks at hatch. Japanese quail
eggs incubated at the lower humidity presented the highest level of
hatchability (79%) compared to intermediate and high humidities.
Egg weight loss was respectively 11.96%, 8.94%, and 4.89% for low,
intermediate and high humidity groups. Furthermore, the weight at
hatch was influenced by the different incubational humidities.
Embryo mortality presented no statistical difference among the
different humidity.
Pedroso et al. (2006) observed 18.56% of early embryo mortality of
Japanese quail eggs incubated at 55% RH. It was reported that high
RH (75-80%) increased mortality and a low RH (40-50%) lowered
late embryo death of eggs laid by older hens (Robertson 1961;
Bruzual et al., 2000).
Ar and Rahn (1980) examined the loss of mass in eggs during
incubation and evidences showed that this was essentially due to loss
of moisture. About 10 to 11% of the moisture is lost in domestic fowl
eggs during the incubation period (Tullett and Deeming, 1987). The
temperature can highly influence the relative humidity, and both
22
contribute to water loss during incubation, this way temperature and
humidity must be carefully monitored during incubation, because the
embryo is not able to control the water loss of egg (Ar, 1991).
2.4 Effect of age on hatchability
Hocking and Bernard (2000) showed that fertility was not affected by
the age of female and male broiler breeders. Hatchability of fertile
eggs were lower and embryonic death were higher in eggs from
female aged 27-29 weeks and 55 to 57 weeks compared with eggs
from birds aged 35 to 37 weeks. The numbers of observed mating
were higher in younger males 27 to 29 weeks old compared with
males of 35 to 37 and 55 to 57 weeks of age. The result suggested that
there may be little difference n the fertility of males and females
broiler breeders at different age when body weight was adequately
controlled to at least 60 weeks of age.
Demmining and Van Middelkoop (1999) reported that increasing
flock age was associated with decreased fertility with probably
reflects a reduced mating frequency. Neither strain nor age affects the
first five days of incubation.
Luykx (1994) collected data on 15600 eggs of broiler breeding hens
of 18 breeds and analyzed. Eggs from hens aged 31, 42, 50 and 60
weeks and stored for 3 days, hatchability of fertile eggs was 90, 93, 89
and 86% respectively V.90,87,86 and 8l% for eggs stored for 10 days.
There were significant difference between breeds in egg characters
and egg storing life.
23
2.5 Effect of egg weight on chick weight
Raju et al. (1997) incubated hatching eggs, from 2 broiler lines,
categorized into 4 weight groups (up to 60g (A), 60.1-65g (B), 65.1-
70g (C) and >70g (D), were incubated after being stored for 0-9 days
at 10-150C. Fertility and hatching weight remained unaffected by egg
size, hatchability decreased with increasing egg weight. Correlations
of egg weight and chick weight were positive. Day old chick weight
increased significantly (P<0.01) with increase in egg weight.
Milosevic et al. (1995) studied on 208 eggs for Ross hybrid was
stored for 5, 10, 15 or 20 days (150 eggs per storage time) at 14-150C
and 70% RH prior to incubation. For the 4 storage times respectively,
egg weight loss was 1.7, 3.2, 4.2 and 5.5% , hatchability 82.6,
74.8,63.3 and 49.8%, mortality among chicks that dead in shell 2.6,
4.1, 5.3 and 6.3%, and chick weight as a percentage of egg weight at
the end of storage 64.0, 67.6,70.4 and 73.0.
Costantini and Panella (1982) incubated 5100 Hubbard eggs, in 5
weekly collections, in 5 weight groups. Egg weight had no significant
effect on egg fertility and hatchability. Chick hatching weight
increased from 35.2 to 45.3g with increasing egg weight (P < 0.01);
the correlation between the 2 traits was 0.95. Egg weight had a
significant effect on chick weight at hatching.
CHAPTER 3
24
MATERIALS AND METHODS
3.1 Collection and storing of hatching eggs
There are 480 hatching eggs (120 RIR chicken, 60 Zending duck and
300 Japanese quail) were collected from Bangladesh Agricultural
University (BAU) Poultry Farm, Mymensingh. The eggs were put on
collecting trays keeping the large end up and stored in the cold room
at 180C-200C with 75-80% RH for 7 days. To keep the actual records
on temperature and relative humidity, dry and wet bulb thermometer
was hung about 1 meter above the eggs.
3.2 Selection and care of hatching eggs
After daily collection, the eggs were scrutinized on the basis of their
physical characteristics such as size, shape, weight, shell texture and
cleanliness of the shell. The good size eggs, uniformly calcified, clean
and sound shell (without any type of crack) were selected randomly.
3.3 Cleaning and disinfection of hatching eggs
Smooth and fine duster was used to remove the dirty materials
adhered to shells of eggs before washing. Finally, the clean eggs were
fumigated by paraformaldehyde (10 gm/m3 for 20 minute).
3.4 Disinfection and fumigation
The incubator was properly cleaned and disinfected with detergent
before setting the eggs in incubator. Before 1st set of eggs, the
incubator was fumigated by paraformaldehyde as per
recommendation (3x strength for 30 min., 1x = 10 g/m3). No
fumigation was performed after setting the eggs in the incubator.
25
3.5 Eggs traying in setter
Eggs were set into the Octagon (Home type) incubator. Each setter
capacity was 250 eggs. Eggs from three different species (chicken,
duck and quail) were set in the same incubator having same
temperature, humidity, turning and ventilation.
3.6 Turning of eggs
The eggs were turned 6 times in 24 hours manually after setting.
3.7 Control of temperature
Temperature was controlled by automatic program as per
recommendation by Octagon hatchery manual. Setter temperature was
37.50C while hatcher temperature was 36.70C. The temperature
maintained during incubation period is given below:
Day Temperature (0C) Humidity (%) Incubator 01-10 10-12 12-14
14-above Normal Run
18 days -21 days
37.8 37.5
37.0 36.7 36.7 36.5
75 75 75 80 80 80
Setter ’’ ’’ ’’ ’’
Hatcher
In the case, when incubator was full sets of eggs, the temperature and
humidity were kept unchanged. However when new sets of eggs were
placed, temperature was adjusted based on the previous set of eggs in
the incubator.
3.8 Control of humidity
During incubation, humidity was maintained as per recommendation
given by Octagon manual. Relative humidity in setter and hatcher
were 75% and 80%, respectively.
3.9 Weighing of eggs
26
At all ages (0, 7 and 14 days), egg weigh records were kept properly,
and then the percent moisture loss was calculated. Average egg
weight was also calculated at all three days of incubation.
3.10 Transfer of eggs
Chicken, duck and quail eggs were transferred from setter to hatcher
at 18th, 24th and 14th days of incubation, respectively.
3.11 Hatching records
Te following records was kept throughout the experimental period.
3.11.1 Candling of eggs
Candling was done at 10th days of incubation period with the help of
an electric candler to identify the clean or infertile eggs or dead
embryos, if any.
3.11.2 Fertility records
During candling, infertile eggs were separated from the fertile eggs.
After completion of hatch, unhatched eggs were examined again to
calculate fertile eggs, if any.
3.11.3 Records of baby chicks hatched and separation of normal
and abnormal chicks
On the 22nd, 29th and 18th day of incubation in chicken, duck and quail
respectively, the chicks hatched out of total eggs were separated and
recorded as normal and abnormal chicks. The chicks belongs to the
abnormal were discarded. Abnormal chicks were lame, blind, poorly
feathered, open naveled, micromelia, organ less etc. After discarding
27
all abnormal chicks the rest were considered as normal and healthy
chicks.
3.11.4 Day old chick weight The day old chick weight was taken in gram using an electronic digital balance and then average was calculated. 3.11.5 Record keeping and data transformation
The following data were calculated from the records kept during the
experimental period:
3.11.5.1 Calculation of moisture loss Initial weight - weight at 14 days Moisture loss (%) = X 100 Initial weight 3.11.5.2 Calculation of hatchability
Hatchability was calculated by adopting the following procedure: Total number of chicks hatched 1) Hatchability on fertile eggs (%) = X 100 Total number of fertile eggs Total number of chicks hatched 2) Hatchability on fertile eggs (%) = X 100 Total number of eggs set 3.11.5.3 Calculation of chick weight as per cent of egg weight Egg weight – chick weight Chick weight (%) = X 100 Egg weight 3.12 Statistical analysis All data either recorded or calculated and analyzed by Completely
Randomized Design (CRD). Analysis of variance was performed to
partition variance into species and error for comparing data among the
species. Significance differences were isolated by calculating Least
28
Significant Difference (LSD) for comparison. A Genstat computer
package was used to analyze the data.
CHAPTER 4
RESULTS AND DISCUSSION
4.1 Egg weight loss (g)
At all ages (0, 7 and 14 days), set egg weight were highest (p<0.01) in Zending duck (60.50g), intermediate in RIR chicken (59.18g) and lowest in quail (9.55g) (Table 1). Egg weight loss at 7 and 14 days of incubation were highest in quail, intermediate in chicken and lowest in duck, which was almost reverse in comparison with the egg weight used in the present experiment. Higher weight loss was from lightest
29
eggs, intermediate in eggs with intermediate weight and lowest weight losses from heaviest eggs were obtained. The current study, suggesting that weight loss may be inversely proportional to weight of eggs. Thus, it appears that the egg weight loss with advance of incubation period simply was the function of egg water loss. Such differenence might have been arisen from depth of the eggs. The heaviest eggs have higher diameter, intermediate size eggs had intermediate diameter and lightest eggs had lowest diameter. This study was supported by Ar and Rahn (1980), who examined the loss of mass in eggs during incubation and evidences showed that this was essentially due to loss of water.
It is evident from figure 1 that the egg weight of 3 species almost linearly depleted with the advance of incubation period. Moisture loss in chicken, duck and quail eggs during incubation periods were almost linear fashion (Figure 2). Chick weight was almost linearly increased with the increase of egg weight, whereas moisture loss maintained a negative relation with the increase of egg weight (Figure 3 and 4).
31
Figure 2. Relation of egg moisture loss% with the advance of
incubation period in different poultry species.
33
Figure 4. Relation of egg weight and egg moisture loss% during incubation period in the different experimental poultry species.
4.2 Moisture loss (%)
Moisture loss percentage was highest (p<0.01) in quail (16.19%),
intermediate in chicken (7.76%) and lowest in duck (7.24%) (Table
34
1). Moisture loss had significant effect on hatchability. The current
study revealed that the higher percentage of moisture loss had a
positive correlation with the egg hatchability. These results agree with
the previous report of Romao et al. (2009), who showed that higher
moisture loss in Japanese quail eggs during incubation gave highest
hatchability in comparison with intermediate and lowest moisture
loss. Tullett and Deeming (1987) also suggested a moisture loss
between 10 to 11% in domestic fowl eggs during incubation results
better hatchability.
4.3 Hatchability (%)
There was no appreciable differences of hatchability on set and fertile
eggs (P>0.05) (Table 2). Apparently, the hatchability on fertile eggs
was similar in chicken (58.3%) and quail (58.9%) and slightly lower
in duck (53.7%). However, hatchability on set eggs was highest in
quail (58.3%) intermediate in chicken (43.3%) and lowest in duck
(40.7%). Difference in hatchability on total eggs and lack of
difference on fertile egg among genotype signifies that, hatchability
on set eggs was just a function of fertility. This results partially agree
with Chaudhry and Alvi (1967), who found that there was no
significant difference in hatchability on fertile eggs between Rhode
Island Red and New Hampshire (p>0.05). These results however
contradict with the report of Swan (1977), who found higher percentage of hatchability (both fertile and set eggs) in meat strain than that of
egg strains. Table 1. Egg weight and moisture loss results of chicken, duck and quail eggs
35
Species Variable
Incubation Period (day)
Chicken Duck Quail
SED Level of significance+
Egg weight (g/egg) 0 59.18b 60.50b 9.55a 1.333 ** 7 56.24b 58.17b 8.74a 1.097 ** 14 54.59b 56.09b 8.00a 0.993 ** Moisture loss (%) 7 4.96b 3.48a 8.48c 0.455 ** 14 7.76a 7.24a 16.19b 0.995 **
+NS, P>0.05; **P>0.01; abc, values having dissimilar superscripts are significantly different; all SED’S are 6 against error degrees of freedom.
Table 2. Hatchability results of chicken, duck and quail eggs
Species Variable Chicken Duck Quail
SED
Level of significance+
Hatchability on set egg (%) 43.3 40.7 58.3 12.02 NS
Hatchability on fertile egg (%) 58.3 53.7 58.9 13.62 NS
+NS, P>0.05; **P>0.01; abc, values having dissimilar superscripts are significantly different; all SED’S are 6 against error degrees of freedom. Table 3. Day old chick weight results of chicken, duck and quail eggs
Species Variable Chicken Duck Quail
SED
Level of significance+
Chick weight (g/chick) 34.56b 37.55c 5.18a 0.853 ** Chick weight as percent of egg weight 58.40b 62.07c 54.24a 1.790 ** +NS, P>0.05; **P>0.01; abc, values having dissimilar superscripts are significantly different; all SED’S are 6 against error degrees of freedom.
4.4 Weight of chicks at hatching
Chick weight at hatchings was highest (p<0.01) in duck (37.55g),
intermediate in chicken (34.56g) and lowest in quail (5.61g) (Table
3). These results suggest that the day old body weight at hatching is
positively correlated with egg weight. This finding is supported by
Costantini and Panella (1982), who observed that chick weight at
36
hatching increased from 35.2 to 45.3g with increasing egg weight (P<
0.01). Egg weight had a significant effect on chick weight at hatching.
4.5 Chick weight as per cent of egg weight
Chick weight as per cent of egg weight was found highest (p<0.01) in
duck (62.07%), intermediate in chicken (58.40%) and lowest in quail
(54.24%) (Table 3). This result revealed that chick weight as per cent
of egg weight was higher in heaviest eggs, intermediate in
intermediate eggs and lowest in lightest eggs, rather species had an
important role. This is might because of moisture loss is less in larger
eggs than that of smaller eggs. Relative chick weight (chick weight as
percentage of egg weight) was in favour of heavier species along with
the egg weight. This result agrees with Raju et al. (1997), who found
positive correlation between egg weight and chick weight. They also
reported that the day old chick weight incresed significantly (P<0.01)
with the increase of egg weight.
CHAPTER 5
SUMMARY AND CONCLUSION
The present study was conducted using eggs of RIR chicken, Zending
duck and Japanese quail at Bangladesh Agricultural University (BAU)
37
Poultry Farm, Mymensingh. The goal of the study was to observe the
effect of moisture loss from the eggs of chicken, duck and quail
during incubation period and the consequence of moisture loss on
hatching results. The eggs of RIR chicken (120), Zending duck (60)
and Japanese quail (300) were incubated artificially in a forced draft
incubator with 3 replications for the eggs of each species, and then
made a comparison on their hatching performance. After cleaning and
washing, only the eggs with uniform shape and good shell quality
were weighed, dipped in disinfectant and then stored blunt end up in a
cool room at 150C to 170C with the 75 to 80% relative humidity. Over
a period of one week, eggs were set for hatching. On the 10th day of
incubation, the eggs were candled to identify and remove infertile
eggs and eggs with dead embryos and the remaining eggs were placed
in pedigree compartments in hatching trays., the number of hatched
and unhatched chicks were recorded on the 22nd, 29th and 18th day of
incubation for the chicken, duck and quail eggs, respectively. Data
were either recorded or calculated and statistically analyzed for
weight of hatching eggs, moisture loss, fertility, hatchability (on set
eggs and fertile eggs), weight of hatched chicks and chick weight as
per cent of egg weight in accordance with the objectives of the
experiment.
At all ages (0, 7 and 14 days), eggs weight was highest (p<0.01) in
Zending duck (60.50g), intermediate in RIR chicken (59.18g) and
lowest in Japanese quail (9.55g). Egg weight loss at 7 and 14 days of
incubation were highest in quail, intermediate in chicken and lowest
38
in duck, which was almost reversed in comparison with weight of the
eggs used in the present study.
Moisture loss percentage from eggs was highest (P<0.01) in quail
(16.19%), intermediate in chicken (7.76%) and lowest in duck
(7.24%). This study revealed that higher percentage of moisture loss
from eggs results the higher percentage of hatchability.
There was no significance differences of hatchability on set and fertile
eggs (P>0.05) among chicken, duck and quail when hatched under
similar environment. Apparently, the hatchability on fertile eggs was
almost similar (p>0.05) in chicken (58.3%) and quail (58.9%) but
slightly lower in duck (53.7%). However, hatchability on set eggs was
highest in quail (58.3%), intermediate in chicken (43.3%) and lowest
in duck (40.7%).
Chick weight at hatchings was highest (p<0.01) in duck (37.55g),
intermediate in chicken (34.56g) and lowest in quail (5.61g). From
this result it can be concluded that heaviest eggs produce heaviest
chicks, intermediate weigh eggs produce intermediate weighed chicks
and lightest eggs produce lightest chicks at hatching.
Chick weight as per cent of egg weight was found highest (p<0.01) in
duck (62.07%), intermediate in chicken (58.40%) and lowest in quail
(54.24%). This result impress that chick weight as per cent of egg
weight were highest in heaviest eggs, intermediate in intermediate
eggs and lowest in lightest eggs, rather species had an important role.
This is might be due to moisture loss, which is less in larger eggs than
the small sized eggs.
39
The following conclusion may be drawn from the current study that:
1. There were no marked variation among species in there
hatchability performances, when hatched under similar
incubator environment and management. Apparently, it was
found that hatchability of quail eggs were better than the
chicken and duck.
2. Moisture loss from eggs had positive impact on the hatchability
of three poultry species i.e. chicken, duck and quail.
3. Chick weight at hatch had a positive correlation with the egg
weight; higher the egg weight - the higher chick weight.
CHAPTER 6
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