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Dana Nigussie van der Waaij Liesbeth H. Dessie Tadelle van Arendonk Johan A. M. 《Tropical animal health and production》2010,42(7):1519-1529
To generate information essential for the implementation of breeding schemes suitable for village poultry producers in Ethiopia,
a survey was conducted aimed at defining the socioeconomic characteristics of the production environments in different geographic
regions, understanding the important functions of chickens, identifying farmers’ choice of chicken breeds and the underlying
factors that determine the choice of genetic stock used. The survey included both questionnaire survey and a participatory
group discussion. A total of 225 households (45 households from each of five Woredas) were interviewed. The questionnaire was designed to collect data covering general information on village poultry production
such as socio-management characteristics, production objectives, population structure, breed choice and trait preferences,
market preferences of specific traits, and farmers’ selection practices. The participatory farmers’ discussions were designed
to involve stakeholders in defining the breeding objective “traits” and deriving their relative importance in the production
environment based on the different functions of chickens and “traits” identified in the interviews. The results showed that
production of eggs for consumption is the principal function of chickens in most regions followed by the use as source of
income and meat for home consumption. The production system in all geographic regions studied revealed similar features generally
characterized by extensive scavenging management, absence of immunization programs, increased risk of exposure of birds to
disease and predators, and reproduction entirely based on uncontrolled natural mating and hatching of eggs using broody hens.
Farmers’ ratings of indigenous chickens with respect to modern breeds showed the highest significance of the adaptive traits
in general, and the superior merits of indigenous chickens to high yielding exotic breeds in particular. Adaptation to the
production environment was the most important attribute of chickens in all the study areas. The high significance attributed
to reproduction traits indicates the need for maintaining broody behavior and high level of hatchability while breeding for
improved productivity of indigenous chickens for village conditions. The market price of chickens is primarily dictated by
weight, but farmers rated growth (males) and number of eggs followed by growth (females) as the production traits they would
like the most to be improved. Therefore, the ultimate breeding goal should be to develop a dual-purpose breed based on indigenous
chicken genetic resources with any of the comb types other than single for all the regions studied having the most preferred
white body plumage for farmers in the Amhara region and red body plumage for those in Oromia, Benshangul-Gumuz, and Southern
regions. 相似文献
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Participatory rural appraisal (PRA), supported by checklists and intensive case studies on individual households, was carried out in three villages at three different altitudes in the central highlands of Ethiopia. The chicken production system in each village is described and the problems are discussed. More than 60% of the families kept chickens, and in most cases the women owned and managed the birds and controlled the cash from the sales. The production systems followed were mainly low-input and small-scale, with 7–10 mature birds per household, reared in the back yards with inadequate housing, feeding and health care. The average egg production per clutch was 15–20, with 3–4 clutches per year. The mean number of eggs set per bird was 12.9±2.2 (n = 160), depending on the size of the bird and season, and the hatching rate was 80.9%±11.1%, range 44%–100% (n = 160). Poultry meat and eggs were generally accepted and appreciated in all three villages. In addition to the small amount of cash income they provide, scavenging chickens have nutritional, cultural and social functions. The flock composition, price of poultry and poultry products, disease outbreaks and hatching of chicks were strongly affected by season. Disease was cited as the most important problem by most of the members of the community, followed by predation, lack of feed, poor housing, insufficient water and parasites. Disease periodically decimated the flocks, and consequently, about 50% of the eggs produced were incubated in order to replace the birds that had died. The major source of loss in the system was the high mortality of chicks (61%) that occurred between hatching and the end of brooding at 8 weeks of age. The system was characterized by no or few inputs and a low output level. The major input was the cost of foundation stock, but after that virtually no cost was involved. The major source of feed for the birds was from the scavenging feed resource base, which comprised table leftovers, small grain supplements and anything edible from the immediate environment. 相似文献
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Whole genome detection of signature of positive selection in African cattle reveals selection for thermotolerance 
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下载免费PDF全文 Mengistie Taye Wonseok Lee Kelsey Caetano‐Anolles Tadelle Dessie Olivier Hanotte Okeyo Ally Mwai Stephen Kemp Seoae Cho Sung Jong Oh Hak‐Kyo Lee Heebal Kim 《Animal Science Journal》2017,88(12):1889-1901
As African indigenous cattle evolved in a hot tropical climate, they have developed an inherent thermotolerance; survival mechanisms include a light‐colored and shiny coat, increased sweating, and cellular and molecular mechanisms to cope with high environmental temperature. Here, we report the positive selection signature of genes in African cattle breeds which contribute for their heat tolerance mechanisms. We compared the genomes of five indigenous African cattle breeds with the genomes of four commercial cattle breeds using cross‐population composite likelihood ratio (XP‐CLR) and cross‐population extended haplotype homozygosity (XP‐EHH) statistical methods. We identified 296 (XP‐EHH) and 327 (XP‐CLR) positively selected genes. Gene ontology analysis resulted in 41 biological process terms and six Kyoto Encyclopedia of Genes and Genomes pathways. Several genes and pathways were found to be involved in oxidative stress response, osmotic stress response, heat shock response, hair and skin properties, sweat gland development and sweating, feed intake and metabolism, and reproduction functions. The genes and pathways identified directly or indirectly contribute to the superior heat tolerance mechanisms in African cattle populations. The result will improve our understanding of the biological mechanisms of heat tolerance in African cattle breeds and opens an avenue for further study. 相似文献
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Livestock keeper perceptions of four indigenous cattle breeds in tsetse infested areas of Ethiopia 总被引：2，自引：2，他引：0
Jennie Stein Workneh Ayalew J. E. O. Rege Woudyalew Mulatu Birgitta Malmfors Tadelle Dessie Jan Philipsson 《Tropical animal health and production》2009,41(7):1335-1346
Four cattle breeds indigenous to western and south-western Ethiopia - Abigar, Gurage, Horro and Sheko - were included in a
study of the perceptions of smallholder cattle keepers regarding cattle management, production levels and constraints for
production. A semi-structured questionnaire was used and 60 cattle keepers from each of the four areas were interviewed. Diseases
were reported as the main constraint to cattle production by a majority of livestock keepers in all areas except in the Sheko
area, where over-stocking was the main constraint. Among diseases, trypanosomosis was the main livestock disease according
to more than half of Gurage, Horro and Sheko keepers, whereas anthrax was most important in the Abigar area. Gurage had highest
age at first calving, longest calving interval and also the lowest milk production, whereas Sheko and Abigar had the most
favorable characteristics both for milk production (600–700 kg) and fertility (age at first mating 3–3.5 years and above 8
calves/cow). Cattle keepers in the Sheko area reported relatively less problems with cattle diseases compared to the other
areas, especially regarding trypanosomosis. Abigar showed a different disease pattern than the other breeds and may also have
advantages as regards trypanotolerance. 相似文献
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Solomon Gizaw Shenkute Goshme Tesfaye Getachew Aynalem Haile Barbara Rischkowsky Johan van Arendonk Anne Valle-Zárate Tadelle Dessie Ally Okeyo Mwai 《Tropical animal health and production》2014,46(5):809-814
Pedigree recording and genetic selection in village flocks of smallholder farmers have been deemed infeasible by researchers and development workers. This is mainly due to the difficulty of sire identification under uncontrolled village breeding practices. A cooperative village sheep-breeding scheme was designed to achieve controlled breeding and implemented for Menz sheep of Ethiopia in 2009. In this paper, we evaluated the reliability of pedigree recording in village flocks by comparing genetic parameters estimated from data sets collected in the cooperative village and in a nucleus flock maintained under controlled breeding. Effectiveness of selection in the cooperative village was evaluated based on trends in breeding values over generations. Heritability estimates for 6-month weight recorded in the village and the nucleus flock were very similar. There was an increasing trend over generations in average estimated breeding values for 6-month weight in the village flocks. These results have a number of implications: the pedigree recorded in the village flocks was reliable; genetic parameters, which have so far been estimated based on nucleus data sets, can be estimated based on village recording; and appreciable genetic improvement could be achieved in village sheep selection programs under low-input smallholder farming systems. 相似文献
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