ABSTRACT
The study was conducted to determine the performance and early lay characteristics of local and crossbred chicken genotypes bearing plumage modifying genes. A total of 170 F1 progenies were generated from the crosses and were used to determine growth and short term egg production characteristics of the crossbred chickens. Data collected were subjected to analysis of variance (ANOVA) while means were separated using Duncan’s Multiple Range Test. Correlation analysis of body weight and egg production characteristics was done using Pearson product moment. All data generated were analyzed using Sas (2004) package. Result obtained showed that there was no significant (p>0.05) difference in day old weight of the local chicken genotypes. However, their crossbred counterparts namely normal feather, naked neck and frizzle chickens were significantly (p<0.05) heavier than the pure local genotypes. It was observed that at the 30th week of life the main crossbreds weighed significantly (p<0.05) higher than the reciprocal crossbreds as well as the pure locals. This showed evidence of maternal influence in which the individuals produced by the local chicken hens weighed less and maintained low body weight due to dam of origin influence. Among the main crossbreds the Na x E was significantly highest in body weight followed by na x E (normal feather x Exotic). The short term egg production parameters among the genotypes showed that the main crossbred individuals had significantly heavier weight at first egg (WAFE) as well as lower age at first egg (AFE). The Na x E which had the highest WAFE also had higher egg number and egg weight than other genotypes. Phenotypic correlation between body weight and age at first egg were higher and positive in the main crossbreds at 0.963 0.954 and 0.963 for F x E, Na x E and E x na and were followed by the pure local genotypes. The total egg weight also showed significant (p<0.01) and positive correlation with egg number in the main crossbred and reciprocals individuals which seem to show hen of origin effect in their manifestaion. There was a positively and significant (p<0.05) correlation between hen day egg production (HDEP), hen housed egg production (HHEP), and age at first egg (AFE) in the reciprocal cross E x Na, while the other genotypes showed poorer correlation which might be due to mortality . Result obtained from regression of body weight at first egg (WAFE) on age of birds at first egg (AFE) showed that the pureline individuals had high and significant R2 values ranging from 75-100% indicating that early prediction of age at first egg ( AFE) can be achieved in hens when records are taken from the early lay production parameters .The findings of this study showed that there were high performance in body weight and egg production characteristics among the main crossbred and reciprocal chicken genotypes bearing the plumage modifying genes. These improved chicken genotypes should be conserved and incorperated into the Nigerian poultry industry.
TABLE
OF CONTENTS
Title Page i
Declaration ii
Certification iii
Dedication iv
Acknowledgement v
Table of Contents vi
List of Tables vii
List of Plates viii
Abstract ix
CHAPTER 1: INTRODUCTION
1.1 Statement of Problem 5
1.2 Objectives of the Study 6
1.3 Justification of Study 6
CHAPTER 2: LITERATURE
REVIEW
2.1 Crossbreeding 8
2.2 Breed Complimentarily 10
2.3 Contributions of Major Genes in Local
Fowl 10
2.4 Nigerian Local Chickens 11
2.5 Growth
and Reproductive Performance of Indigenous Chickens in Nigeria 13
2.6 Egg Production 14
2.6.1 Clutch number, clutch size and hatchability 15
2.6.2 Egg weight 16
2.6.3 Age at sexual maturity or first egg 16
2.7 Body Weight 16
2.7.1 Single major gene effects 17
2.7.2 Factors affecting egg production in chicken 18
2.7.3 Age at sexual maturity (ASM) 18
2.7.4 Nutrition factor affecting egg production 19
2.7.5 Temperature effect on egg production 20
2.7.6 Effect of dangerous gases on egg production 21
2.7.7 Effect of diseases on egg performance 21
2.8 Floor Space Management 22
2.8.1 Photostimulation on egg production 22
2.8.2 Genetic parameters on the chickens’
performance 23
2.9 Heritability 24
2.10 Regression and Correlation of Egg
Production Parameters 25
2.10.1
Hen day egg production and hen housed egg production percentage 26
CHAPTER 3: MATERIALS
AND METHODS
3.1 Location of Study 27
3.2 Management of Base Population 27
3.2.1 Mating schedule of the base population 28
3.2.2 Egg collection for incubation 28
3.2.3 Candling and Incubation 29
3.3 Management of F1 Progenies 29
3.3.1 Laying period 30
3.4 Data Collection 30
3.5 Measurement of Egg production 31
3.7 Estimation of Phenotypic Correlations 32
CHAPTER 4: RESULT
AND DISCUSSIONS
4.1 Body Weight of Pure line, Main and
Reciprocal Crosses of Normal,
Naked
Neck Feather and Frizzle Feather Chicken Genotypes from
0 to
30 Weeks of Age 34
4.2 Feed Intake of Pure line, Main and
Reciprocal Crosses of Normal,
Naked
Neck and Frizzle Feather Chicken Genotypes from 2 to 30
weeks
of Age 38
4.3 Growth Performance of the Pure and
Crossbred Local Chicken Genotypes from 0 to
7
Week of Age 40
4.4 Growth Performance of the Pure and
Crossbred Local Chicken Genotypes at 8 to 10
Weeks
of Age 43
4.5
Growth Performance of the Pure and
Crossbred Local Chicken Genotypes from Week
10
to Week 16 45
4.6 Growth Performance of the Pure and
Crossbred Local Chicken Genotypes from
18
to 30 Weeks of Age 48
4.7 Egg Production Parameters of Pure, Main
and Reciprocal Crosses of Normal,
Naked
Neck and Frizzle Feather Chicken Genotypes 52
4.8 Phenotypic Correlations between Body
Weight and Egg Production
Parameters
of Pure lines, Main and Reciprocal Crosses of Normal
feather,
Naked Neck and Frizzle Feather Chicken Genotypes 58
4.9 Regression of body Weight of Bird at
First Egg (WAFE) on Age of Bird at
First
Egg (AFE) of Pure lines, Main and Reciprocal Crosses of Frizzle,
Naked
Neck and Normal Chicken Genotypes 61
4.10 Multiple Regression of Early Lay Parameters
on Egg Number for
Pure
lines, Main and Reciprocal Crosses of Frizzle, Naked Neck and
Normal
Chicken Genotypes 63
CHAPTER 5: CONCLUSION
AND RECOMMENDATION
5.1 Conclusion 66
5.2 Recommendation 67
REFERENCES 68
APPENDICES 98
LIST OF TABLES
4.1
Body weight of pure
line, main and reciprocal crosses of normal,
naked
neck and frizzle feather chicken genotypes from 0 to
30
weeks of age 35
4.2 Feed intake of pure line,
main and reciprocal crosses of normal,
naked
neck and frizzle feather chicken genotypes from week 2 to
week
30 39
4.3
Growth performance of
the pure and crossbred local chicken genotypes
from
week 0 to week 7 42
4.4
Growth performance of
the pure and crossbred local chicken genotypes
at 8
to 10 week 44
4.5
Growth performance of
the pure and crossbred local chicken genotypes
from
week 10 to week 16 47
4.6
Growth performance of
the pure and crossbred local chicken genotypes
from
week 18 to week 30 49
4.7
Egg production
parameters of pure, main and reciprocal crosses
of
normal, naked neck and frizzle feather chicken genotypes 53
4.8
Phenotypic correlations
between body weight and egg production
parameters
of pure lines, main and reciprocal crosses of normal,
naked
neck and frizzle feather chicken genotypes 60
4.9
Regression of body
weight of bird at first egg (wafe) on age of
bird
at first egg (afe) of pure lines, main and reciprocal crosses of
frizzle,
naked neck and normal chicken genotypes 62
4.10
Multiple regression of
early lay parameters on egg number for
pure
lines, main and reciprocal crosses of frizzle, naked neck and
normal
chicken genotypes 65
LIST
OF PLATES
1: F1
Normal x
Normal 90
2: F1
Frizzle x Exotic 90
3: Naked
neck x exotic layer (Isabrown) F1 91
4: Parent Stock Naked Neck Cock X Exotic layer 92
5: Parent
Stock Frizzle Cock X Exotic 93
6: Normal
X Exotic Layer F1 94
7: Normal X Exotic layer F1 95
8: Naked Neck x naked neck F1 96
9: Parent stock, Normal x Exotic layer (Isa brown) 97
CHAPTER 1
INTRODUCTION
Crossbreeding
refers to the crossing of two or more genetically unrelated population or lines
that is, it could be different breeds, strains or inbred lines or even
different species.It is aim at combining the gene in both population in the
resulting progeny thereby creating greater variability. New combination of
genes generally results from such crosses, and favourable ones are used use to
bring about improvement. Crossbreeding with the exotic strains increased body
weight greatly at 2 weeks of age (Adebambo et
al., 2006) . Akinwumi et al. (1979)
gave an estimate of about 123.0 million for indigenous fowls and 9.6 million
for exotic birds. Lufadeju et al. (1995) and Lamorde (1997)
estimated the Nigerian local chickens population at 150 million. However, the
Federal Ministry of Agriculture and Rural Development (FMARD) (2008) gave the
estimated number of indigenous chicken in Nigeria as 166 million. These local chicken populations are consisted
of mixed varieties of unimproved, unselected and random breeding birds (Udeh,
2010). Poultry is by far the largest livestock group and has been predicted to
be about 252.3 million consisting of chickens, ducks and pigeons (BBS, 2009). Poultry
constitute 30% of animal protein and will increase to 40% in the future (IFPRI,
2000). They are characterized by low adult body weight of 0.68 0-1.71kg for the
male and 0.43 – 1.35kg for the females (Nwosu, 1979, Oluyemi and Ogunmodebe,
1979). The growth rate of the local chickens is also generally much slower than
that of commercial broilers (Pym et al.,
2013). While broilers under typical confinement rearing may reach 2.0kg live
weight at five weeks of age, indigenous cockerels birds often weigh no more
than 1.0kg at 20 weeks (FAO, 2010), studies have shown that indigenous stock
under good conditions, perform
marginally better, or under low input and harsh conditions (Tadelle et al., 2000; Singh et al., 2004). There exists biodiversity that manifest in the
genetic variants within and among the local genotypes of chickens distributed
around the world (Khobondo et al., 2015).
These genetic variants have changed as the result of domestication selection
and breeding (Khobondo et al., 2014).
Chicken populations are now grouped into wild populations, indigenous and local
lines that are unselected but domesticated, selected lines for quantitative
traits such as industrial layers and broilers and experimental study lines
(Weigend and Romanov, 2001).The trendy world breeds of chicken are grouped into four evolutionary lineages,
egg-types, chicken of Mediterranean origin, chicken of Asiatic origin,
meat-type chickens of Asiatic origin and true bantams of various origins
(Moiseyeva et al., 2003).Local or indigenous chicken, among
chicken species, probably show the highest rate of variation of production
types for the indigenous birds characterized so far in Nigeria, Botswana,
Kenya, Malawi, Sudan, Ethiopia, and so on
great changes is observed in morphological characteristics and products
parameters (Kingori et al., 2007). With respect to body weight, three
variants identified among local chicken are dwarf, normal low and heavy body
weights (Khobondo et al., 2015). The
shank and skin are also frequently coloured showing green, grey and blue
variants. In addition, melanin deposition in skin, meat, internal organs and
bones are also encountered in some genetic groups (FAO, 2010). Nwosu et al. (1985) reported that the
commonest plumage colour patterns of the indigenous birds were black, red,
brown with various laced colours and motllings. Plumage pigmentation is varied
but mainly tends towards blackish and brownish colours showing extended and
pied colourations (Khobondo, 2015). Plumage distribution is mainly normal while
special forms such as naked neck, frizzle and silkness appear sporadically. The
comb is mostly single but rose, pea, walnut, duplex and crests are also present
(Khobondo et al., 2015). Some of
these changes are due to the presence of major morphological marker genes which
increases the adaptability of these strains to tropical climatic environments.
These genes could be divided into three categories which are: feather reducing
genes, genes that reduce body size and genes that control plumage colour (FAO,
2010).The genes were associated with ecological zones the feather birds genotype
are predominant in wet climate, their body is well protected with feathers to
assist in insulation and protection against dissipating body heat. The warm and
hot climate is dominated by naked necks and frizzle feather compression caused
by incomplete dominant genes Na and F respectively, a feather that allows
better heat lost (Khobondo et al.,
2015). The naked neck genotype is characterized by featherless skin on the
neck, on the breast and on ventral part of the thigh (Khobondo et al., 2014). Akinokun (1990) reported
in the study of indigenous chicken and exotic birds in Nigeria stressing that
exotic chicken are relatively inferior
in the tropical environment than in their zones of descent in terms of
survivability, adaptability and prolificacy, although the expected higher
productivity was recorded over their local chicken counterparts. In several
studies however, indigenous chickens have been compared with exotic chickens in
the tropics, although the exotic outperformed their local counterparts in many
ramifications, though performance is relatively poor compared with what is
obtained in their region of descent (Adebambo, 2003). The egg production of
native chickens have being referred to as low compared to the foreign strains.
Nwosu (1979) and Obioha et al. (1983)
submitted that the egg production for the indigenous bird ranged from 60-80
eggs per annum under extensive system with an average egg weight of
32.75g. Other authors including Oluyemi
(1974), Akinokun and Dettmers (1977) and Adegbola et al. (1986) have also reported on the small egg size and number
of the indigenous chicken. Nwosu (1985) reported that there was no major
difference in the egg laying performance of Nigeria local chickens of the
eastern strain versus Nsukka strain and the Awgu strain. Peters (2000) also confirmed
that normal feather hen laid highest numbers of eggs than the exotics. Horst
(1989) reported that the indigenous chickens are abundantly endowed with about
7-9 major genes existing in their genes pool that are generally conserved for
special utility in the tropics. The presence of these major genes make them
jealous for genetic exploration (Peter, 2000). Research shows that the egg
number laid per clutch range from 4 to 14 eggs. Sonaiya and Olori (1990)
reported that an average of 9 eggs was laid within the period 12 days. Ikeobi et al. (1996) reported that the
production of 8 to 9 eggs per clutch was laid within the period of 2 to 14 days
during a laying period 32 to 36 weeks. Nwosu and Omeje (1985) evaluated the egg
laying performance of indigenous chicken and reported that their production
ability is in the range of 40 to 80 eggs, although their genetic potential for
egg production is about 125 eggs. Major genes of chicken are believed to confer
not only adaptability to the tropical climate, but also resistance to disease (Haunshi
et al., 2002). Reports on the
influence of the major genes such as naked neck and frizzle on immune
competence are few (Mahrous, 2008).Some of the major genes such as slow feathering
dwarfism have been studied for their possible influence on immune competence in
fowl (Klingensmithh et al., 1983;
Bacon et al., 1986).Significantly
Higher Cell Mediated Immune (CMI) estimate was observed in Naked neck (Nana)
and normal feather (nana) broilers as compared to nana (Patra et al., 2004; Martin et al., 1989) who submitted that there
was no significant effect of naked neck and frizzle gene on cell-mediated
immune (CMI) response. Heterozygous naked neck (Nana) genotype had a better
cellular and humeral response than their normally feathered (nana) and
homozygous naked neck (NaNa) genotype also the normal plumage hens had a higher
mortality and culling rate than heterozygous naked neck hens (Mahrous, 2008). The
problems of shortage of food in the ever
increasing population of Nigeria calls for an urgent need to conserve and sustain the indigenous stock of chickens in order to avert animal
nutrition imbalances and or crisis. Poultry plays an important role in human
nutrition, employment and income generation (Talukder et al., 2010).The Nigerian native chickens is one of the major
sources of protein to the Nigerian people (Ogbonna et al., 2002). The importation of foreign strains of chicken because
of factors such as high reproduction cycle, low unit cost, bigger eggs and
higher body weight has being at the detriment of the native chicken (Agaviezor et al., 2011). It is an anxiomatic truth
that the potentials of the indigenous chicken has not been fully utilized since there are still growing reports
about existing or potential levels of productivity in the strain managed under extensive system (Mathur et al., 1989). Genetic upgrading of
native chicken stock is necessary because of its high adaptability to harsh
environmental condition of climate and disease compared with the exotic stock
(Fitzhugh et al., 1992, Ajayi, 2010).
The report of Adedeji et al. (2004)
showed a significant improvement in the growth performance of pureline naked
neck, frizzle feathered and normal feathered local chickens. This shows an
indication that the genetic profile of the chickens can then be upgraded via
different breeding schemes.
1.1 STATEMENT
OF PROBLEM
Over
the years, local chicken productions have been plagued by inadequate selection
by untrained specialists as such many strains of genetic merits have been
threatened to extinction. The proportion of indigenous chicken such as the
frizzle feather and Naked neck are no longer high in some areas of the Niger
Delta region in Nigeria especially in Bayelsa state. The unsustained use of
these local poultry genetic resource by local farmers is partly responsible for
the decline in their population. Lack of planned breeding and conservation
backed up by strong government policy on conservation and multiplication of
endangered livestock and poultry species are further reasons for the decline in
number of these rare poultry stock. The
indigenous chickens have some major genes which help in disease resistance,
hardiness, mothering ability and ability to survive hash weather conditions
over time. However, they have been responded to slow growth rate, inability to
lay many eggs, and inability to reach market size within short period of time.
This has however reduced market interests in the local chicken and therefore
all efforts should be geared toward chicken based research in order to increase
the performance ability and growth rate of our local poultry stock through
crossbreeding and selection schemes.
1.2 OBJECTIVES
OF THE STUDY
The
broad objective of this study is the evaluation of growth performance and early
laying characteristics of indigenous crossbred chicken genotypes bearing
plumage modifying genes.
The
specific objectives of the study include:
i.
to evaluate body weight changes of pure,
maincross and reciprocal crossbred chicken.
ii.
to evaluate the production parameters of these local chicken genotypes.
iii.
to evaluate early lay characteristics of
the birds.
iv.
to determine phenotypic relationship
between body weight, and the egg production parameters
v.
Regression of early lay production parameters
on age at first egg (AFE)
1.3 JUSTIFICATION
OF STUDY
Protein
malnutrition is a serious and common experience in developing countries of the
world, particularly as the protein intake of these part of the world fall far
below the recommendation of FAO (FAO, 1991).Genetic improvement of local
chicken population can take many forms but it must follow an ordered hierarchy
of events which starts from understanding of production and marketing systems,
choice of appropriate breeds or strains that can sometimes lead to replacements
of existing breeds (Sola-Ojo, 2011). Indiscriminate crossbreeding of species by
untrained breeders have created ecological imbalance of viable breeds/strains
into the wild by contaminating our poultry genetic resources.Due to the
inability to handle, conserve and provide suitable environment has therefore, led
to the destruction of chicken genetic resources in our ecological system. Many
characteristics of economic importance have been thrown diluted or destroyed
because of inadequate breeding skills and managerial ability which has led to
near extinction of some chicken strains. The study therefore would help in providing
baseline information for genetic improvement of the local chickens, their
crossbreds and the way forward towards their conservation.
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