Purposes of keeping goats, breed preferences and selection criteria in pastoral and agro-pastoral districts of South Omo Zone

Tekleyohannes Berhanu, Jamroen Thiengtham*, Sayan Tudsri**, Girma Abebe***, Asrat Tera and Somkiert Prasanpanich*

Southern Agricultural Research Institute, P. O. Box 06, Hawassa, Ethiopia
tekleyo22@yahoo.com
* Department of Animal Science, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
** Department of Agronomy, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
*** Department of animal and Range Science, Hawassa University, P. O. Box 05, Hawassa, Ethiopia

Abstract

The study was conducted to describe the purposes of goat keeping, breed preferences and selection criteria in Hamer and Bena-Tsemay pastoral and agro-pastoral districts of South Omo zone. Data were collected through household interviews using structured questionnaires administered to 250 respondents.  

All the goats in the study districts are indigenous genotypes. In both districts, goats are kept primarily for socio-economic purposes and secondly for socio-cultural functions. The role of goats as a source of meat, milk and blood was ranked third. The households valued highly for adaptation traits of goats such as tolerance to drought and disease resistance above performance traits. The households’ 88% in Hamer and 70% in Bena-Tsemay districts prefer dual purpose goat genotypes (meat and milk) than either meat or milk types. Over 90% of households have own bucks for breeding. The households in the study districts consider larger body size and reproductive performance characteristics of individual goats and their relatives when selecting replacement animals. The study indicated that the information obtained would assist in planning suitable goat breeding and extension programs in the zone.

Keywords: adaptation, breeding, dual purpose, extension, traits

Introduction

Ethiopia is believed to have the largest livestock population in Africa. It has been estimated that there are more than 21 million goats in the country (CSA 2009). The Southern Nation, Nationalities, and People's Region (SNNPR) of Ethiopia with an estimated area of 112,343.19 square kilometers, possess the country’s 20% cattle and 15% small ruminant populations (CSA 2009).  

Currently, the role of goats in improving the income and livelihood of rural people in the region is gaining importance (Kocho et al 2011). In South Omo zone of SNNPR, approximately 297,486 pastoral and agro-pastorals people inhabit along the Omo river valley keeping large number of cattle, sheep and goats (PCC 2008).  The pastoral and agro-pastoral districts possess 98% of the estimated 912, 889 goat population of the zone; almost all being indigenous breeds (CSA 2009). There is a need to improve the live weight and meat production potential of the goats through selection and crossbreeding with boar goats that were imported by the Regional Bureau of Agriculture (SNNPR-BoA) with the cooperation of the USAID-funded program called Ethiopian Sheep and Goat Productivity Improvement Program (ESGPIP). To this effect, the Southern Agricultural Research Institute (SARI) in collaboration with SNNPR-BoA is planning to establish a boar goat crossbreeding center and setting forth a community based goat selection and breeding programs in the region for improving local goats (SARI 2011).  

However, sustainability of such programs would depend on producer’s interest which could also be influenced by socio-cultural, economic and geographical factors (Ilatsia et al 2012). An understanding of producer’s trait or breed preferences and selection criteria would enable breeders in SARI/SNNPR-BoA or other regions to effectively design sustainable genetic improvement programs that would make possible to develop and promote appropriate goat genotypes that match with the prevailing socio-economic and cultural environments (Gwaze et al 2009; Bett et al 2011). More importantly, an understanding of selection criteria of pastoral goat keepers would provide information for deciding how to approach small ruminant herders in order to establish community-based breeding programs (Mbuku et al 2006).This study was therefore, undertaken to explore the purpose of goat keeping, breed preferences and selection criteria used by pastoral and agro-pastoral households in South Omo zone.  

Material and methods

Descriptions of the study area 

The study was conducted in Hamer and Bena-Tsemay districts of South Omo zone. The districts are located 4º 27’-5º 39’ north and 35º 23’- 37º 49’ east, bordering Kenya to the south. The study districts are characterized by semi arid and arid climatic conditions, with mean annual rainfall increasing from the extreme south lower part, with some 350 mm, to the upper part where it ranges to 1400 mm. The districts have high ambient temperature ranging from 26 to 35ºC. The dominant types of land use in Hamer district is pastoralism while that of Bena-Tsemay is agro-pastoralism. The two districts possess 60% of the goat population from the pastoral and agro-pastoral districts of South Omo zone. The Hamer, Bena and Tsemay are the major ethnic groups in the study districts (SOFEDB 2009). 

Sampling procedure, Study design and data analysis 

After selection of the two districts namely; Hamer (representing the pastoral area) and Bena-Tsemay (representing the agro-pastoral area) a two stage sampling technique was used. In the first stage, kebele’s (the lowest administrative-sub units) and villages were selected based primarily on distribution of ethnic groups and population of goats. In the second stage, respondent households were randomly selected from the villages using systematic sampling procedures. The distribution of the samples per study districts was presented on Table 1. 

To collect data a structured questionnaire was prepared which was pre-tested and administered by trained enumerators. The variables that were analyzed for the study districts were household characteristics, goat herd size and structure, purpose of keeping goats, household’s breed preference, criteria for selection and culling of goats. The data were collected from January to May 2011 and analyzed using the Statistical Package for the Social Sciences (SPSS) version 17. Means were compared using the Chi-square test and descriptive statistics such as means, standard deviations and percentages. Rankings on treatments were done as implemented by Kosgey et al (2008).  

Results

General household characteristics 

The average family size in Hamer and Bena-Tsemay districts was 6.7 and 6.6, respectively. Female and male children of age below 15 constitute more than 45% of the family size in both districts. Male headed households comprise 81 and 86% of respondents in Hamer and Bena-Tsemay district, respectively. About 90% and 72% of the household heads in Hamer and Bena-Tsemay, respectively, were illiterate. However, the respondents in Hamer and Bena-Tsemay districts had goat keeping experience of 24.5±13.1 and 19.9±14.5 years, respectively. In both districts, sale of livestock is the main source of income. Sale of livestock products such as honey, milk and butter in Hamer and sale of crops such as sorghum, maize, millet, barley, wheat and tef in Bena-Tsemay are the second greatest source of income for the respondents. In both districts, sale of goats is the greatest income source from livestock followed by cattle.  

Herd size and structure 

The average herd size of goats per household was 66.7±54.2 and 41.8±31.2 in Hamer and Bena-Tsemay district, respectively. Adult male (>1year), adult females (>1year), weaners (6-12 months) and kids constitute 21.6, 43.9, 21, and 13.4% of the goat herd in Hamer district. The corresponding values for Bena-Tsemay district was 20.6, 40, 24.4, and 15%, respectively. Overall, male and female goats constitute 38.6 and 61.3% of the herd composition in Hamer and 30.2 and 59.8% in Bena-Tsemay district, respectively. The majority of households in the districts reported a decline in goat numbers for the last 5-10 years, prevalence of diseases and drought occurrences being the major factors for the decline. 

Purpose of keeping goats 

The households in the studied districts raise goats for multiple purposes which are categorized into three (adapted from Ayalew et al 2003): (1) Socio-economic (cash, asset, security); (2) Production or yield attributes (meat, milk, blood); and (3) Socio-cultural (rites, ceremony, dowry) purposes. Rankings on the purposes by the households were presented on Table 2. In both districts, goats are kept primarily for socio-economic purposes and secondly for socio-cultural functions. The role of goats as a source of meat, milk and blood was ranked third. However, the proportion of households ranking goats as a source of meat, milk or blood was significantly higher in Hamer than Bena-Tsemay district. On the other hand, a significantly higher number of households rear goats as a source of cash in Bena-Tsemay than Hamer district. 

Source of genotypes and perception on traits 

All households in the study district own indigenous goat genotypes which are identified by their locality or tribe names as Hamer, Borana, Dasenech, Galeb, Bena, Tsemai, Ari, Malle, Kenya or Gebere goats. The majority of pastoral households reported that the origin of goats was from Borana (west of the study districts), Dasanech and north Kenya (South of the study districts) whereas some of the households in the upper part of Bena-Tsemay district reported Malle area and Gofa zone (North of the study district) as the source for their goat types. 

The households have varying perceptions on performances of goat types within their locality. The Hamer ethnic groups perceive their goats (Hamer goats) as inferior to Borana goats in terms of body size and milk production. However, they believe that their goats are superior to the Dasenech or Geleb goats in growth performances. On the other hand, the agro-pastorals in the north extreme parts (Argo meda area) stated that Malle goats are superior to the goats in the lowland pastoral areas in terms of body size and milk production and twining potential. The households also indicated that there is high variability in performance traits within their goat genotypes. 

The proportion of households’ rating for adaptation and productive traits of goats was presented in Table 3.  Generally, the households rated highly for adaptation traits of goats such as tolerance to drought and resistance for diseases above growth performance trait.  With respect to birth types of goats, 95% of households in Hamer and 82% in Bena-Tsemay districts stated that the goats are frequently giving birth to singles whereas twining in goats was reported only by 4 and 18% of the households in the respective districts.  

Breed preferences by the households 

The households, 88% in Hamer and 70% in Bena-Tsemay districts preferred dual purpose goat genotypes (meat and milk) than either meat or milk types. However, a significantly higher proportion of households prefer for meat type goats in Bena-Tsemay than Hamer district (27.3 vs. 6.5%). On the other hand, the proportion of households demanding for milk type goats is higher in Hamer district than Bena-Tsemay (4.9 vs. 2.3%). Generally, higher demand for improved goat genotype was observed by the households in Bena-Tsemay district than Hamer. In other words, as a constraint, the households in Bena-Tsemay district prioritized according to their importance disease, shortage of feed, water scarcity, lack of improved goat genotype and access to market. However, for the majority of Hamer pastorals improved goat genotype is the least in priority. 

Selection criteria of breeding animals (buck and doe) 

The pastoral and agro-pastoral households in the study districts consider the body size and reproductive performances of the individual and its relatives when selecting replacement animals for the next generation. However, breeding practice in both districts is uncontrolled since goats are herded and living together throughout the year. The proportion of households selecting bucks for breeding are 97 and 66 % in Hamer and Bena-Tsemay districts, respectively. The sources of breeding buck for the households were presented on Table 4. Within owner’s herd was the main source of breeding bucks for 98 and 90% of the households in Hamer and Bena-Tsemay district. Sharing bucks from neighbors is the second source of buck for breeding. Breeding bucks were selected in their order of importance based on large body size (including length, height and conformation), coat color, horn, and relative’s performance history. Bucks with brown or red colors with black or brown spots/stripes are the preferred colors whereas bucks with whole or dominantly black colors are not preferred due to their low market values. The respondents also stated that bucks with brown, red or black spots/stripes (mixed colors) reproduce more than other bucks. Bucks with horns are selected for breeding and bucks with large, curved and good looking horns are also considered as a prestige and have high market value. 

The proportion of households selecting does for breeding are 77 and 31 % in Hamer and Bena-Tsemay districts, respectively. The households selection criteria for replacement does in their order of importance was based on fast kidding interval (twice a year), good maternity (alertness, long and wide tail, long and large teat), large body size and conformation and prolificacy of parents (Table 5). The main reason for making culling decision of goats is sickness due to diseases, poor performances and old age. The culling age for female and male goats was 6.0±2.1 and 6.6±1.9, in Hamer district and 7.3±3.0 and 6.7±3.2 in Bena-Tsemay district, respectively.  

Discussion

The multiple roles of sheep and goats in rural regions with arid and semiarid climates have been well described (Bosman et al 1997; Peacock 2005). The present study revealed that in pastoral and agro-pastoral areas of southwestern Ethiopia, next to the economic importance of goats, a powerful cultural and religious tie exists with goat production as was also reported for cattle in the area (Strecker 1976; Gustaf and Silvester 2008). Studies indicate that grains/cereals are the primary source of food for the households in pastoral and agro-pastoral districts of South Omo (Strecker 1976; Admasu et al 2010). This could be one reason for the households least ranking of goats as a source of meat, milk and blood. However, the significantly higher percentage of ranking households in Hamer district indicates the greater role of goats as a source of meat, milk and blood for Hamer pastoral households than Bena-Tsemay. It has also been reported that in marginal rural regions with arid or semiarid climates goats have greater role in the household’s strategy to achieve food security (Peacock 2008).  

The present study showed that all goats in the study districts are indigenous genotypes which are generally recognized according to the areas where they occur. It has been reported that 99.9% of Ethiopian goats are indigenous genotypes (CSA 2009). Names given to indigenous goat types of the country also reflect mainly their geographical location or ethnic affiliation (Tesfaye 2004). Even though recent characterization works are lacking, broad physical descriptions of the goats in southern Ethiopia have been given (FARM-Africa 1996) and the goats are also generally considered as a separate indigenous goat genetic entity (Tesfaye 2004). However, the varying environments and sources of origin for the goats in the present study as stated by the pastoral and agro-pastoral households may have varying effect on the morphological characteristics and production performances of goat populations within south western Ethiopia.   

In the current study, the pastoral households’ low rating for growth performance traits was mainly due to the smaller body size and poor body conformation of their goats. However, the households indicated that within their goat genotypes there is considerable variation in productive traits such as twining, meat and milk production potential. Environmental variations or the dissimilarity in source of goats within/between the districts could be the factors for the variability in production performances within the existing goat genotypes. The potential use of this variability, however, needs to be investigated. Holst (1999) reported that the desire to increase livestock performance through selection begins with the individual farmer when he realizes that there is variation within his flock or between flocks in his region. Reports also indicate that the adaptation and welfare of extensively farmed livestock can be further improved through within breed selection (Simm et al 1996). Kosgey et al (2006) also indicated that there is great scope for conservation, genetic improvement and utilization of the indigenous small ruminants in east Africa, which makes village-based breeding programs more attractive.  

The households in the present study rated highly for the adaptability traits (drought tolerance and resistance to endemic diseases) indicating that their goats are not inferior to other goats in their vicinity including the Borana goats with respect to reproductive and adaptation traits. There are also indications that goats in south western Ethiopia are known to live in areas where trypanosomiasis is endemic (FARM-Africa 1996), various tick borne diseases are rampant (Mekuria et al 2008) and recurrent droughts are prevalent (Admasu et al 2010). It has also been reported that disease resistance including litter size, fleece type and the ability to store body fat, some aspects of behavior, especially maternal and grazing behavior are among the traits conferring better adaptation of animals in extensive conditions (Simm et al 1996). Hence, there have been opportunities for natural selection for the traits to these environments and, thus, an understanding of the adaptive traits and their inclusion in the breeding goal is an important consideration for the effectiveness of a genetic improvement programs involving introduction of improved breed other than local goats for extensive systems (Simm et al 1996). A better understanding of the relationships between production traits and adaptation traits will also be critical for the development of appropriate, sustainable breeding programs (Simm et al 1996). Moreover, it has been reported that in the developing countries, a breeding program involving improved, indigenous breeds and their crosses need to be evaluated in relation to socio-economic value, fiscal constraints, religious rituals, responsiveness to indigenous knowledge and the traditional skills of the producer (Kosgey et al 2006; Shrestha and Fahmy 2007). Bett et al (2009) also stated that in animal breeding the best animal or breed is the one fitting the breeding objectives and the farm environment.  

The preference of the majority of households for dual purpose goats indicates that meat and milk are important for the pastoral and agro-pastoral households in the study districts. Since goat’s milk is mostly used for the household’s nutrition, the greater preference for milk type goats in Hamer district may indicate the greater role of goat milk in the household’s nutrition in Hamer district than Bena-Tsemay. On the other hand, the households in Bena-Tsemay district are relatively more diversified due to favorable environment for crop and cattle production (Admasu et al 2010); therefore, for the households in Bena-Tsemay district goats’ milk is less important, especially for those in the upper part of the district. The high demand for meat type and improved goat breeds in Bena-Tsemay district indicates the relatively higher economic role of goats in the district compared to Hamer district since greater proportion of households in Bena-Tsemay district rear goats for income source than food (meat, milk and blood) compared to the Hamer district though the economic role of goats outweigh the other roles of goats (source of food or social functions) in both districts. 

In the current study, the majority of households (>90%) have their own bucks for breeding. In the pastoral/extensive system usually higher percentage of farmers’ rear their own males for breeding purpose compared with the smallholder (Kosgey et al 2008). However, 50 to 60% of the households in the present study also borrow or share bucks from their neighbors unlike in north Kenya where pastoral/extensive farmers tend to purchase than borrow when males were not reared (Kosgey et al 2008).  This is because the pastoral and agro-pastoral tribes in South Omo zone have a cultural tradition of stock sharing (male or female) through bond friendship which is considered as a means to minimize risk and accumulate wealth (Strecker 1976). Therefore, it is uncommon for a pastoralist to refuse if another asks for an animal (buck/doe in this case) to rear on a share-basis or for a loan for a certain period for breeding. 

The present study reported that the pastoral and agro-pastoral households consider growth and reproductive performances of the individual and its relatives when selecting animals for replacement. This was in agreement with the practices of pastoral communities in north Kenya (Mbuku et al 2006).  The greater proportion of households practicing selection (buck and doe) in Hamer district than Bena-Tsemay may have been associated with the greater flock size of goats in Hamer district than Bena-Tsemay. Use of body size and performance characteristics by the households as criteria for buck and doe selection observed in the current study is similar with other reports (Kosgey et al 2008; Kebede et al 2012). It has been reported that livestock farmers in general place more weight on morphological selection criteria (subjective selection) than production selection criteria (objective selection) (Tabbaa and Al-Atiyat 2009). However, selection criteria might differ with breed, herd size, production system and marketing opportunity available in their area (Tabbaa and Al-Atiyat 2009; Kebede et al 2012).  

The household’s preference for brown or red coat colors with black or brown spots/stripes in the current study was due to the higher market value for the goats and because of the household’s assertion that colored goats reproduce better than the dominantly black or white. With respect to market, for example, dried and unprocessed goat skins are used to make traditional leather garments for pastoral girls or women in South Omo zone (FARM-Africa 1996; Gustaff and Silvester 2008). According to the households studied, white goat skin is not preferred for traditional leather garments over brown or red. White coat color is also less preferred by some pastoral households because they consider it as an invitation to predators and thieves when goats graze away from the homesteads. The assertion that colored goats reproduce better than the dominantly white or black, however, was not consistent for the black color (Ebozoje and Ikeobi 1998). On the other hand, it has been reported that pastoral communities in north Kenya use coat color of the animals as the most important identification system within and without their flocks, in addition to branding and ear notching (Mbuku et al 2006). 

Conclusions

• The present study described the purposes, breed preferences and selection criteria used by pastoral and agro-pastoral households in the study districts. The households indicated that within their goat genotypes there is considerable variation in productive traits such as meat, milk production and twinning potential. The potential use of this variability, however, needs to be investigated. A genetic improvement program which may be sought for the areas involving introduction of improved breeds other than local goats should considered in the breeding program growth performance and the adaptability traits such as drought tolerance and resistance to endemic diseases. The knowledge obtained from the current study would assist in promoting suitable goat genotypes such as dual purpose (meat and milk) or milk types to specific localities in the zone.

Acknowledgments

For the financial support provided, the authors are grateful to the Rural Capacity Building Project, Ministry of Agriculture and Rural Development of Ethiopia. Thanks are also due to Southern Agricultural Research Institute of Ethiopia for providing research facilities and study leave to the first author. 

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Received 27 August 2012; Accepted 26 October 2012; Published 2 December 2012

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