Breeding strategies for low input systems
1996
Bradford, G.E. (University of California, Davis (USA). Department of Animal Science) | Subandriyo | Doloksaribu, M. | Gatenby, R.M.
Genetic improvement is an efficient and practical means of improving the productivity and product quality from small ruminant enterprises. Genetic improvement can be effected by changing the breed composition of the flock, and by selection within flocks. Breed substitution, partial or complete; can lead to large one-time increases in genetic potential but should only be done with breeds that have been shown to be equal or superior, in fitness as well as in production traits, to the stock they will replace. This superiority should have been documented in the production environment in which they will produce. Breeds of temperate climate origin often have impaired fitness in the tropics. Once an appropriate stock has been identified, selection within that stock can result in cumulative increases of one to two percent per year, leading to large increases in productivity over time. The challenge for smallholder systems is to obtain a large enough population size to permit such selection. In the absence of a central source, for example a government flock of breeding stock being continuously improved, a cooperative effort among smallholders of a village or region can be used to achieve an adequate population size. Suggested approaches for two potential population sizes are outlined
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