Genetische Anzeichen für Mechanismen der Adaptation und Produktion in westafrikanischen Rinderpopulationen.

The current project based on the hypothesis that environmental challenges contribute to genetic characteristics of west-African cattle breeds being associated with adaptation, robustness and heat tolerance. Furthermore, social-ecological transformations in the African context may initiate breeding processes towards improved productivity and product quality. For inferring the respective genomic mechanisms, 449 cattle of the local breeds Borgou, Pabli-Kerou, Lagune and Somba were genotyped using the 50K SNP chip. Based on the first two principal components, breeds could be clearly allocated to different clusters, displaying further sub-clusters for the respective historical populations. Obvious was the large genetic distance with high-yielding German cattle breeds such as HF. A particularity of the genomic studies addressing selection signatures was the possible contrasting with the respective historical populations to infer genetic processes of transformation by time. The annotated potential candidate genes contributed to physiological pathways and mechanisms inducing immunity and adaptation. The detected gene RNF220 has well-known effects on calving ease in HF. Genome-wide associations for measurements of morphological traits could be associated with heat tolerance and disease resistance. The quite large heritabilities for continuous body measurements in cm indicate potential for further optimizations of genetic evaluations for conformation traits. Whole-genome sequencing of the west-African breeds contributed to the detection of four novel milk protein variants, illustrating the importance of west-African genetic resources to improve product quality. [ABSTRACT FROM AUTHOR]