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91.
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   
92.
Poverty, drought, and hunger devastate people on Africa's rangelands. We used an action-oriented approach from 2000 to 2004 to build capacity among thousands of pastoralists to diversify livelihoods, improve living standards, and enhance livestock marketing. The process included collective action, microfinance, and participatory education. Poor women previously burdened by domestic chores became leaders and rapidly changed their communities. Drought occurred from 2005 to 2008. We assessed intervention effects on household drought resilience with a quasiexperimental format that incorporated survey-based comparisons of treatment groups with ex post controls. Interventions led to major improvements in trends for quality of life, wealth accumulation, hunger reduction, and risk management. Human capacity building can be a driver for change, generating hope and aspirations that set the stage for the use of new information and technology.  相似文献   
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