Breeding objectives and breeding plans for Washera sheep under subsistence and market-oriented production systems
2024
Gizaw, Solomon | Haile, Aynalem | Dessie, Tadelle
A Washera sheep breed improvement project has been initiated in Amhara state, Ethiopia. However, breeding objectives and breeding plans/schemes to achieve the objectives have not been formally defined. In this study, we identified two Washera sheep production systems (subsistent and market-oriented). Breeding objectives addressing the two production systems were defined applying bio-economic models. The results indicate that twinning rate is economically the most important trait in both production systems. The results also indicate that a single selection index and hence a single breeding program could meet the breeding objectives of both systems. An index containing six-month weight, twining rate and survival rate (or combined as number of lambs weaned) and feedlot gain could be used in Washera sheep improvement programs. Two alternative nucleus breeding schemes (a regional and zonal scheme) were planned and evaluated for their genetic and economic efficiency and operational feasibility. The regional scheme is designed to address the entire Washera sheep population (1.2 million), while the zonal scheme will serve part of the population. The regional scheme gives 58.9% more returns to investment. However, the nucleus size is too large to operate as a single flock. The nucleus could be split into multiple smaller flocks which need to be genetically linked through ram exchanges and across-flock genetic evaluation so that the nuclei operate as one big nucleus. Yet such a regional scheme seems to be operationally infeasible under the existing conditions. Operationally feasible breeding program for Washerasheep could be developed by setting up multiple independent nuclei for each zone with approximately 10% of the population. Such nuclei could be established for each zone gradually as resources allow.
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