Conservation-based breeding program design for genetic improvement in Gumz sheep in the western lowlands of Ethiopia

Abstract Background Genetic improvement in livestock in developing countries like Ethiopia remains challenging; selection-based breeding schemes have the potential to provide resource-poor producers with access to improved animals that could ensure increased productivity of animals and hence contribute to reduced poverty. Therefore, the aim of this study was to compare alternative breeding program designs to improve productivity of Gumz sheep for sustainable utilization and conservation of genetic resource. In this paper, two village-based and two central nucleus-based sheep breeding schemes were modeled and evaluated in terms of their biological and economic efficiencies. The schemes were scheme-1: a village-based breeding scheme with existing lambing, scheme-2: a village-based scheme with improved lambing, scheme-3: central nucleus-based scheme with 5% nucleus size and scheme-4: central nucleus-based scheme with 10% nucleus size. Results The annual genetic gains per year in 6-month weight (kg) were differed across schemes and ranged from 0.154 to 0.171 in village-based scheme, and 0.334 to 0.336 in central-based schemes. The annual genetic gain per year in number of lambs born per ewe bred ranged from 0.0017 to 0.0036% in both village- and central nucleus-based scheme. The genetic gain in the proportion of lambs weaned per ewe was comparable across central nucleus-based scheme but little differed in village-based schemes and ranged from 0.0015 to 0.0016%. Conclusion Central nucleus-based schemes resulted in the highest genetic gain and economic efficiencies in all breeding objectives compared to village-based schemes. However, this scheme requires establishing a very large central nucleus flocks. Village-based scheme with estrous synchronization was the best option. The expected genetic gains and profits were higher as it promotes participation of farmers and achieving concentrated lambing which in turn increase selection intensity and genetic progress. This suggested the possibility for sustainable Gumz sheep improvement and conservation through village-based schemes and estrous synchronization