Master's Thesis, 2012, 102 Pages
2. LITERATURE REVIEW
2.1. Origin, Domestication and Classification of Chicken Population
2.1.1. Origin and domestication
2.1.2. Classification of indigenous chickens
2.1.3. Chicken population in Ethiopia
2.2. Characterization of Indigenous Chicken Ecotypes of Ethiopia
2.2.1. Production system
2.2.2. Phenotypic characterization (qualitative traits) of indigenous chicken ecotypes
2.2.3. Performance (quantitative traits)
2.3. Comparative Advantage of Chicken
2.4. Definition of Breed
2.5. Breeding Objectives and Practices
2.5.1. Farmers breeding practice
2.5.2. Modern breeding practice
2.6. Indigenous Knowledge in Management of Chicken Gene Pool
2.7.1. Prevalence of disease, housing system and predation
2.7.2. Management system and feeding
2.7.3. Market system
3. MATERIALS AND METHODS
3.1. Description of Study Area
3.2. Study Methods
3.2.1. Sampling framework and data collection procedures
3.2.2. Data collection procedure
3.3. Data Management and Statistical Technique
4. RESULT AND DISCUSSION
4.1. Respondent’s and Owner`s Profile
4.2. Flock Size and Structure
4.3. Flock Dynamics within Six Month
4.4. Qualitative Traits
4.5. Chicken Production System
4.5.1. Feeding and feed resource
4.5.2. Housing and House facility
4.6. Breeding Objectives and Practice
4.6.1. Farmers breeding practice
4.6.2 Mating system and culling practice
4.6.3 Trait preference of farmers
4.7. Incubation Practice
4.8. Purpose of Chicken Production and Social Taboos
4.9. Socio-Economic and Marketing of Chicken Products
4.10. Major Constraints
4.10.1. Diseases and mortality
4.11. Indigenous Knowledge in Gene Pool Managements
4.13. Good and Bad Attributes of Indigenous Chicken
4.14. Reproductive and Productive Performance
4.14.1. Reproductive performance
4.14.2. Production traits
4.15. Quantitative Traits Analysis
4.15.1. Linear model
4.15.2. Linear model for male
4.15.3. Linear model for female
4.16. Phenotypic Correlation
4.17.1. Principal component analysis
4.17.2. Discriminate analysis
4.17.3. Stepwise discriminate analysis
4.17.4. Clustering analysis
4.18 Description of Major Chicken Ecotypes
4.19. Breeding Objective
4.19.1. Description of components of breeding program
4.19.2. Production system, stakeholders, and infrastructures of the study area
4.19.3 Selected traits for genetic improvement in the study area
4.19.4 Proposed breeding program
5. CONCLUSION AND RECOMMENDATION
I would like to pass my great gratitude and thanks to those individuals, interviewed chicken producer, farmers and those institutions involved directly or indirectly in this work to success of my study.
First, my deepest appreciation and heartfelt thanks goes to my major research advisor Dr. Zewdu Wuletaw and co-advisor Dr.Hailu Mazengia for spending precious time to give me constructive and regular advice starting from proposal.
I would also like to extend my acknowledgment to Dr.Mengesha, head of livestock department in North Wollo zone of Amhara region for his smoothing the working condition by informing all district BoARD officers. Furthermore, I would like to thanks Ato Belay, the assigned person in poultry sector in Sirinka research institution for his valuable advice and soft ware and material support.
I would like to acknowledgment to Bahir Dar University for offering resources to conducted research activity per time. And I also would like to acknowledged staff members of Animal Production and Technology for their advice to be success academically and other general knowledge.
Finally, I would like to thank my friend Mekdes Gemechu for her financial and moral support.
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Phenotypic characterization of indigenous chicken ecotypes was conducted in North Wollo from January 2011 to May 2012 with the objectives of characterizing indigenous chicken and their production system. Simultaneously, identification of development intervention for improved utilization of chicken genetic resources was also identified. In the first part of data collection, one focused group discussion per agro-ecological zones was held. Then, administration of well-structured questionnaire and morphometric measurement were employed. Measured quantitative traits of chicken among the three altitudes were analyzed by linear model of SAS 2002 for male and female chickens separately. Subsequently, mean value of each traits were compared using Tukey’s mean comparison method. Multivariate analysis of principal component analysis, canonical discriminant, step-wise discriminant and clustering analysis was performed by SPSS 19.0 for male and female chicken ecotype separately. Nechi ( 17.6% ), Tikur ( 12.6% ) and Key ( 10.8% ) plumage colour were found dominantly all over the study area. Findings of the focus group discussion revealed that there were morphologically differences among chickens of high altitude, mid altitude and low altitude study areas. Similarly, findings from the semi-structured questioner revealed that indigenous chicken ecotypes are dual-purpose, adapted to wide range of environments, and managed under traditional and largely subsistent mode of production. The critical constraints of scavenging chicken production were disease (60.13%) predators (20.59%) and feed shortage (19.28%). Number of egg lay/clutch (37.91%) and plumage colour (37.58%) were the major preferred trait by the farmers in the study area. For qualitative and quantitative study, 715 sample chickens were recorded by category of agro-ecology. Linear measurements on six traits were taken from 210 mature male and 305 mature female chickens. The overall mean body weight of indigenous male and female chickens was 1500.97gm and 1253.36 gm respectively. The overall age at sexual maturity for male and female was 24.25 ± 0.04 and 23.84 ± 0.05 weeks respectively. There was highly significant difference (p<0.0001) in egg production/hen/clutch across altitudes. Based on linear model analysis and result of focus group discussion, observed morphological variation and multivariate analysis, three chicken population found in North Wollo was categorized in to high altitude, mid altitude and low altitude chicken ecotypes. Egg production, meat yield and diseases resistance were trait preferred by farmers to be improved. By understanding flock size, production system, trait preference of farmers, traditional or cross breeding program would be implemented to improve the productivity of indigenous chicken.
Key words: Indigenous chicken ecotype, phenotypic characteristics, breeding objectives, North Wollo
Ethiopia is believed to have the largest livestock population in Africa. This livestock sector has been contributing considerable portion to the economy of the country. The livestock sector contributes 20% to the total GDP, supporting the livelihoods of 70 % of the population and generates about 11% of annual export earnings. Livestock sector are still promising to rally round the economic development of the country (CSA, 2011).
Indigenous chicken (97.3 %) in Ethiopia is found in huge number distributed across different agro-ecological zones (CSA, 2011) under a traditional family-based scavenging management system (Alemu & Tadelle, 1997). This indicates that they are highly important farm animals kept as a good source of animal protein and income to most of the rural populations. Furthermore, their widespread distribution indicates their adaptive potential to the local environmental conditions, diseases and other stresses (Halima, 2007). The total chicken egg and meat production in Ethiopia is estimated to be about 78,000 and 72,300 metric tons respectively (Fisseha et al., 2010a). From that, more than 90% of the national chicken meat and egg output is from indigenous chickens (Nigussie, 2011).
However, the productivity of indigenous chicken is low as compared to exotic breeds with average annual egg production of 60 eggs/hen (Fisseha et al., 2010a). On the other hand, the live weight of indigenous chicken is about 1.6 kg and 1.3 kg for male and female respectively at 6 months of age (Mekonnen, 2007). This initiate the government to modernize poultry production by introducing exotic breeds since 1990s (Abebe, 2008). This indiscriminate introduction of exotic genetic resources, before proper characterization, utilization and conservation of indigenous genetic resources is the main cause of the loss of indigenous chicken genetic resource (Halima, 2007).
Indigenous chicken production has a comparative advantage over other livestock’s for the that reason of they have short-time generation interval, low feed consumption, high breeding ability with low breeding costs and they have a capacity to have a great number of quails per unit area (Upton, 2004).
Disease (Serkalem et al., 2005), predation (Halima, 2007), market system (Bogale, 2008), management and production system (Fisseha et al., 2010a) were major constraints of chicken in scavenging production system of Ethiopia.
The rural household in Northwollo administration zone has an average 0.7 hectare of land (compared to the national average of 1.01 hectare of land and a regional average of 0.75 for the Amhara region (http://en.wikipedia.org/wiki/Semien_Wollo_Zone). According to CSA (2011), there were around 14,048,486 chicken populations in Amhara region, of which Northwollo administration zone accounts 1,132,383 chicken populations. Therefore, to support the livelihood of these small land holders and landless including women’s improving chicken productivity may be the highest priority in the fight against food insecurity in the area. However, these genotype of existing chicken has to be characterized for their overall merits and need subsequent improvement.
Improvement of the productivity of indigenous chicken resource demands characterization of the available genotypes. So far, only limited efforts were made to characterize the existing chicken ecotype of the country on a comprehensive standard. In general, indigenous chickens are non-descriptive, with a variety of morphological appearances (Halima, 2007; Mekonnen, 2007). Tadelle (2003) studied five indigenous chicken ecotypes up to 18 weeks of age, which were selected from different parts of Ethiopia. Duguma (2006) also studied on phenotypic characterization of indigenous chicken of Ethiopia at Debre Ziet Agricultural Research Center. Characterization in smallholder poultry production and market system in three districts of SNNPRS (South Nation Nationality People Regional States) was conducted by (Mekonnen, 2007). In addition, Bogale (2008) dealt with Characterization of poultry productivity and market system in Fogera district. Halima (2007) studied on phenotypic and genetic characterization indigenous chicken in Northwest Ethiopia. Nigussie (2011) also examined on morphological and genetic characterization indigenous chicken in different part of Ethiopia with regard to breeding practice and traits preference of farmers, very limited efforts were made. None of the above-mentioned workers include the indigenous chicken genetic resources of North Wollo zone of Amhara |Regional State. Breed improvement and subsequent proper utilization of these local chicken genotypes strongly demands comprehensive characterization, including breeding practice, Therefore, this study was initiated with the following objectives.
- To identify and characterize indigenous chicken ecotype of North Wollo administration Zone in terms of physical characteristics, production system and performance
- To identify trait preference and breeding practice of the farmers in identified indigenous chicken ecotypes
- To outline priority areas of intervention for genetic improvement of the identified indigenous chicken ecotype population based on farmer trait preferences, and
- To identify the main problems hindering proper utilization and conservation of chicken genetic resources in the study area, and forward suggestions on how these constraints should be solved
Chicken has been the most popular poultry species worldwide in terms of their number and economic importance. Taking in to account the geographic range of the species (Crawford, 1990), archaeological discoveries (West and Zhou, 1998), protein polymorphisms and morphological characteristics (Moiseyeva et al., 2003), domestic chicken were derived from red jungle fowl. Furthermore, another study based on DNA, indicated that the ancestor of the domestic chicken was a particular sub-species of the Red Jungle Fowl (Gallus gallus gallus) (Fumihito et al., 1994). Similarly, in a series of studies that analyzed 400 base pairs of the mtDNA D-loop region of four species of genus Gallus (Gallus gallus, Gallus sonnerrati, Gallus lafayetti and Gallus varius), three sub-species of Gallus gallus (G.g gallus, G.g spadiceus, G.g bankiva) and nine domestic breeds of chicken from south Asia, south east Asia, Japan, Europe, shows an evidence which suggests that domestic chicken are derived from G.g gallus (Akishinonomiya et al., 1996).
In general, the idea of Akishinonomiya et al. (1996) on evolutionary history of chicken could be summarized in to three phases. The first phase started with the evolution of the genus Gallus, followed by the emergence of the domestic fowl from its progenitors and lastly the appearance of the large number of the current chicken breeds, varieties, strains and lines.
Crawford (1990) indicated that chicken with black feathers, meat, bones were found in Mozambique in 1635, bearing the fibromelanosis mutant known at the India not Europe. This implies that India is the most likely origin of chicken that imported to Africa (Nigussie, 2011). In another way, Halima (2007) states that there is no information that shows introduction of chicken in to Ethiopia.
The Ethiopian indigenous chickens are none descriptive breeds closely related to the Jungle fowl and vary in plumage color, comb type, body conformation and weight. They are characterized by slow growth rate, late sexual maturity and low production as well as reproductive performance (Meseret, 2010). In Ethiopia, limited attention has been given to characterization and classification of indigenous non-descriptive chicken ecotypes and research is at its rudimentary stage for the identification, description (Halima, 2007).
Non-described indigenous chickens in Ethiopia are found in huge numbers distributed across different agro-ecology categories under a traditional family-based scavenging management system (Alemu & Tadelle, 1997). Only small portion of Ethiopian indigenous chicken were identified and characterized. These includes Tilili, Horro, Chefe, Jarso and Tepi (Tadelle et al., 2003), Gelila, Debre-Elias, Melo-Hamusit, Gassay, Guangua and Mecha (Halima, 2007) and Farta, Konso, Mandura and Sheka (Nigussie, 2011) were the major chicken ecotypes found in different part of Ethiopia (Table 2.1).
Table 2.1. Some Indigenous chicken and their special features
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Note: D.E, Debre Elias; M. H, Melo-Hamusite
In 2003, more than 35 million indigenous chickens were estimated (CSA, 2003). However, it shows an increment to 49.3 million chickens in 2011 of which 97.3% (48.3 million) were indigenous (CSA, 2011). Regionally: Oromia, Amhara and SNNPR take the first, second and third position in chicken population size respectively (Table 2.2).
The average flock size of indigenous chickens kept per rural smallholder family varied from 6 to 10 (Halima, 2007). Nevertheless, according to Nigussie (2011) the average estimated size of indigenous flocks per household is about 3.5 (ranging from 2.1 in Konso to 6.5 in Sheka).
Table 2.2. Regional and national chicken population ('000) distribution in Ethiopia
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Phenotypic characterization of AnGR used to refer the process of identifying distinct breed populations and describing their characteristics and their production environments (FAO, 2010). It should also include the population size of the animal genetic resources, its physical description, adaptations, uses, prevalent breeding systems, population trends, predominant production systems, description of the environment in which it is predominantly found, indications of performance levels (meat, growth, reproduction, egg) and the genetic distinctiveness of the animal (Weigend and Romanov, 2001). The Ethiopian indigenous chickens are none descriptive breeds closely related to the Jungle fowl and vary in plumage color, comb type, body conformation and weight (Hailu, 2007) management scavenging system (Tadelle et al., 2003).
The most dominant chicken production is scavenging type of production system using a majority of indigenous chicken ecotypes with only seasonal/conditional feed supplementation (Halima, 2007; Mekonnen, 2007; Fisseha, 2009). The main feed resource in scavenging chicken thought to be insects, worms, seeds, plant materials, etc. with very small amount of grain and table left over supplements from the household and characterized as low input and output (Tadelle, 1996).
A study conducted in Northwestern part of Ethiopia by Halima (2007) revealed that 50.77% of farmers kept their chicken outside the main house in sheds built for other purpose. Only 22.1% of chicken owners in Bure district prepared a separate overnight house for chickens and the rest (77.9%) kept chickens in various night sheltering places (Fisseha et al., 2010b). These and other traditional chicken management systems negate productivity of indigenous chicken (Nigussie, 2011)
The indigenous chickens of Ethiopia have various names and characterized on different grounds, as in many other parts of Africa. Chicken show heterogeneity in terms of plumage colour, shank length, comb type and growth performance (Fisseha et al., 2010a). Alemu and Tadelle (1997) indicated that indigenous chicken in Ethiopia vary widely in body size, conformation, plumage color and other characteristics. Based on their plumage colour the indigenous chicken ecotypes named as Tikur , Key , Gebsima and Netch, Ambesma, Seran, Libework, Netch Teterma, Tikur Teterma, and Key Teterma (Bogale, 2008).
The production performances of indigenous chicken ecotypes were relatively poor. The low egg production performance of indigenous chicken was expressed as slow growth rate, late maturity, produce small sized eggs, small clutch size, broodiness and high mortality of chicks (Bogale, 2008; Fisseha, 2009; Meseret, 2010).
Mean annual egg production of the indigenous chicken ecotype was 30-60 egg (under village condition) and pointed that; this could be improved to 80-100 eggs on station with improved feeding, housing and health care (Nigussie and Ogle, 2000). The total number of eggs produced per hen per year ranges from 18-57 (Halima, 2007). Another study shows that total egg production/hen/year of indigenous hen’s ranges from 53-60 within a range of 43.2-46.96gm of egg weight under farmer management condition (Fisseha et al., 2010b). The average estimated length of a single egg-laying period per hen is to be 21, 36 and 105 days for local, hybrid and exotic breeds (CSA, 2011).
The overall mean egg laying performances of hens for the first, second and third clutches were 17.0, 20.9 and 24.8 eggs respectively (Tadelle et al., 2003) with average number of 16 (ranged 8 - 28) eggs laid/clutch (Fisseha et al., 2010a). The total number of clutch periods/hen/year was 4 (ranged 2 – 6) with annual egg production performance of 60 eggs/hen (ranged 24 -112) under farmer’s management condition (Fisseha et al., 2010a). According to Bogale (2008) the average number of eggs incubated/hen was 13 from this on average 11 chicks were hatched. A laying hen needs about 120-130 days to accomplish one production cycle that is 40 - 50 days of laying, 21 days of incubation and 60 days of brooding chicks.
Even though the productivity of indigenous chicken under good housing, feeding and management system don`t reach to an economically acceptable level, they show an increment (Alemu and Tadelle, 1997). Indigenous chicken produce eggs with thicker shells than leghorns. Furthermore, fertility of eggs from indigenous chickens was found to be higher than Leghorns (Solomon, 2003).
Various reports indicated that the meat production ability of indigenous chicken were limited and is measured based on growth performance (FAO, 2010). Growth performance from seven indigenous chicken populations found within a range of 1045- 1517g (male) and 642-874 (female) live weight at the age of 22 weeks. This is much lower when compared to the average weight of Rhode Island Red breeds (1736 and 1263 for respective sexes) kept under the same environment (Halima, 2007). Local males may reach 1.5 kg live weight at 6 months of age and females about 30% less is with the carcass weight of 550 gram, which was significantly lower than White Leg Horn 875gm (Bogale, 2008). However, indigenous chicken breed has a higher dressing percentage (Alemu and Tadelle, 1997). According to Solomon (2003), there was no difference between White Leghorn and indigenous chickens raised under scavenging condition in mean daily body weight gain at 2 months of age. In addition, he reported that the indigenous chickens are sold for meat purpose starting from 6-8 months of age at weight of around 700-1400g. Mean body weight at the start of laying was 1035 + 34g with a range 985 - 1113g.
Age at sexual maturity of indigenous female chicken was attained at 6.8 months (Tadelle et al., 2003). Another study in Fogera district revealed that the average age of indigenous chicken to reach sexual maturity is 5.9 +0.11 and 5.87+0.1 months for female and male (Bogale (2008). According to Fisseha et al. (2010a), the average age of cockerels at first mating and pullets at first egg laying were 24.6 weeks and 27.5 weeks respectively in Burie district.
A study conducted by International food policy research institute indicated that chicken is one of the potential areas to develop in the livestock subsector, primarily to create employment and generate income through reduction of risk factors (Alemu et al., 2008). In developing countries, nearly all families at the village level, even the poor and landless, are owners of chicken. Chicken production has the following pros:
- Chicken are mainly owned and managed by women and are often essential elements of female-headed households
- Chicken are socio culturally important with few religious taboos attached
- Production is feasible at village level, where only low cost technology is needed to improve production considerably
- Low investments are required to achieve such change
- Land ownership is not a constraint
- Scavenging production is environmentally friendly (Upton, 2004)
- Chicken production increased because of the following qualities: Short-time generation interval, low feed consumption, high breeding ability, capacity to have a great number of quails per unit area, low breeding costs and high resistance to diseases.
The term “breed” is difficult to define, but most often understood as “a group of domestic livestock with definable and identifiable external characteristics that distinguish it from other groups within the same species” (Ilse, 2000). Similarly either a sub specific group of domestic livestock with definable and identifiable external characteristics that enable it to be separated by visual appraisal from other or it could be explained as, defined groups within the same species or a group for which geographical and/or cultural separation from phenotypically similar groups has led to acceptance of its separate identity (FAO, 1999).
Even though it is difficult to control mating of chicken in scavenging production system, farmers have their own criteria and strategies of selecting chickens for breeding (Halima, 2007; Bogale, 2008) based on plumage colour, comb type, egg production and growth rate (Fisseha et al., 2010a). All farmers in different regions of Ethiopia practiced selection on breeding and replacement males and females based on four trait categories: plumage color, live weight, comb type, and body conformation “qumena” (Nigussie, 2011). Here as a comment farmers found in Horro, Sheka, Farta, Konso and Burie district have selection of chicken to have a property but they might not control their chicken mating.
Farmers in the Amhara (Farta) and Oromia (Horro) regions give the highest emphasis for plumage color where as farmers in the Southern region of Ethiopia (Konso and Sheka) select live weight of chicken as primary trait interest. With regard to comb type, double comb is preferred to single comb type (Bogale, 2008). In other countries, the most important traits of farmers were growth rate, disease tolerance, egg yield, body size and fertility in Jordan and Kenya respectively (Abdelqader et al., 2007; Okeno et al., 2011).
Even though many indigenous chicken ecotypes have better adaptation to the local environments (e.g. better foraging capabilities, anti-predator behavior and/or innate resistance to infectious diseases), they remain poor egg-layers and broilers due to lack of selection for productivity traits and poor levels of husbandry (Nigussie, 2011). Low productivity of indigenous chicken ecotypes in traditional production initiates the government to modernize poultry production by introducing high yielding exotic chicken breeds (Abebe, 2008).
Importation was in the form of fertile egg, DOC, pullet and cockerels by PMDCs, medium-scale and large-scale commercial importers of poultry both at the private and public sectors. Public sector importers include the agricultural research institutes such as debre zeit agricultural research centre, Kombelch, Andassa. Another study disclosed that both scientists and government have promoted schemes in which exchange of cockerels from selected strain or breed could improve the performance of indigenous chickens (Fisseha et al., 2010b). However, infield the distribution of exotic blooded chicken were scared
Socially embedded customs influencing the gene pool were: taboos on selling female animals, outside community, devoting male animals to memory of an ancestor, rules for passing on animals from one generation to next, sharing mechanisms, religious ceremonial use (white animals for cleansing bad omens, black animals for curses), animal important for rituals, ceremonies require animals with particular coat colours and patterns, body select animal to get wide spectrum of colours, detailed knowledge of pedigrees and inheritance of colour patterns (www.lifeinitiative.net).
The first major causes of chicken death/loss were seasonal outbreaks of diseases, mainly Newcastle disease (Serkalem et al., 2005; Bogale, 2008; Fisseha, 2009). In addition to Newcastle diseases, coccidiosis and fowl typhoid are the major cause for chicken mortality (Mekonnen, 2007; Bogale, 2008) followed by predator (Halima, 2007). Another study conducted in Bahir Dar and Farta district discloses infectious bursal disease (IBD) is one of the most important viral diseases of chickens (Hailu et al., 2009).
Village chicken production in Ethiopia characterized by lack of separate house prepare for their chicken (Halima, 2007; Bogale, 2008; Fisseha, 2009; Fisseha et al., 2010a). This exposes the chicken to predator and infectious diseases (Bogale, 2008) in Fogera district. Predations were the major constraints in village chicken production (Halima, 2007; Mekonnen, 2007; Fisseha et al., 2010b). Wild birds (“chilfit”) were the first major and dangerous types of predators followed by “Aner” and wild cats (Fisseha, 2009). The attack of predator in Fogera district is very serious on young chicks (Fisseha et al., 2010a).
Productive performance of village chickens was relatively low because of genetic and non-genetic factors. Production losses due to poor chicken management (feeding, housing and health care) were disclosed in Bure district (Fisseha, 2009). The nutritional status of local laying hens from chemical analysis of crop contents indicated that protein was below the requirement for optimum egg production. The deficiency is more series during the short rainy season and dry seasons (Alemu and Tadelle, 1997).
The price of live chickens and eggs fluctuate seasonally: more demand on holidays and fasting seasons at that time the price increase (Halima, 2007; Mekonnen, 2007). In human methods of transporting chicken and egg to market create physical injury and other complications on the chickens and eggs that reduce the quality of products and income (Bogale, 2008).
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