![]() ![]() The African breeds involved are two West African taurine Muturu from Nigeria and N’Dama from Guinea, and eight East African zebu breeds Aryashai, Baggara, Kenyan Boran, Butana, Fulani, Gash, Kenana and Ogaden. The full genome sequences of an average of ten representative samples of ten different African cattle breeds were recruited in our attempt to achieve this goal. Thus, the primary goal of the research presented herein is to unravel at genome-wide level the genome diversity and particularly the genetic basis of economically important phenotypes including morphology (growth traits), productivity (milk production traits) and local environmental adaptation traits such as disease resistance, heat tolerance and tick resistance traits of indigenous African taurine and zebu cattle through signatures of selection analyses. Alternatively, recent approaches have been suggested to identify key genome regions with remarkable footprints due to selection pressures the detection of signatures of positive selection. This may be typically done using genome-wide association in pedigree resource populations. However, a prerequisite for this approach is the understanding of the genetic mechanism and identification of the genome regions that have been subjected to both natural and artificial selection and underlying economically important traits including environmental adaptation (Ellegren and Sheldon 2008, Cosart et al., 2011, Lee et al., 2013). In such a context, a possible way forward would be to do ‘informed’ crossbreeding by combining the adaptive traits of the indigenous breeds with the productivity traits of the exotic ones. This may be achieved by breeds replacement (importation of exotic breed, but it means changing the production system), within breed improvement (but takes time) or crossbreeding of exotic with local breeds (work but often only for the F1 generation not beyond). We are faced with the challenges of improving livestock productivity on the African continent in order to meet the ever increased demands for livestock product due to population growth. However, the productivity of African cattle is generally low compared to the exotic cattle breeds in other parts of the world (Andersson 2001, Groeneveld et al., 2010). Indigenous African cattle represent a unique set of cattle population as of their adaptation to the conditions of their local environments, which is characterized by a diversity of climatic conditions (hot and dry, hot and humid, cold etc.), prevalence of livestock diseases, including parasitic and tick-borne diseases, and periods of food shortages as results of semi-intensive to extensive management system. It follows domestication, migrations, human and natural selection of animals including adaptation to different climatic conditions, local environmental and production conditions. There is an overwhelming phenotypic diversity observed among domesticated animals compared with what is observed in wild species. ![]() ![]() Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader Genome diversity and adaptation of African Taurine and Zebu cattle.
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