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A total of 183 adult sires belonging to nine West African cattle breeds sampled in 67 villages of Mali, Burkina Faso and Benin were assessed for 16 body measurements and 18 qualitative traits. Within type of cattle (zebu, sanga or taurine), the different breeds analysed showed large differences in body measurements. In general, taurine breeds had lower average values than the zebu breeds while sanga cattle tended to have intermediate values. Principal component analysis identified three factors characterising body measurements. Factor 1 summarised the information provided by those traits characterising the size of the individuals and explained 59.0 % of the variability. Factor 2 tended to gather information characterising the body width and explained 8.0 % of the variation. Less representative, Factor 3 (6.6 % of the variability) had no clear interpretation. Qualitative traits did not allow to distinguish among either cattle groups or breeds. Two Correspondence Analysis Dimensions computed on qualitative traits (explaining 26.2 and 15.5 % of the variability, respectively) did not allow to differentiate between zebu, sanga or taurine cattle breeds. Our results confirm that, in the framework of a general appearance, body measurements are the main criteria for differentiating West African cattle breeds. Furthermore, the current research has not allowed to identify breeding preferences on qualitative type traits in West African cattle sires. Therefore, homogenisation of the appearance of individuals within cattle breed is not expected.

Up to 173 African sires belonging to 11 different subpopulations representative of four cattle groups were analysed for six Y-specific microsatellite loci and a mitochondrial DNA fragment. Differences in Y-chromosome and mtDNA haplotype structuring were assessed. In addition, the effect of such structuring on contributions to total genetic diversity was assessed. Thirty-five Y-chromosome and 71 mtDNA haplotypes were identified. Most Y-chromosomes analysed (73.4%) were of zebu origin (11 haplotypes). Twenty-two Y-haplotypes (44 samples) belonged to the African taurine subfamily Y2a. All mtDNA haplotypes belonged to the "African" taurine T1 haplogroup with 16 samples and nine haplotypes belonging to a recently identified subhaplogroup (T1e). Median-joining networks showed that Y-chromosome phylogenies were highly reticulated with clear separation between zebu and taurine clusters. Mitochondrial haplotypes showed a clear star-like shape with small number of mutations separating haplotypes. Mitochondrial-based FST -statistics computed between cattle groups tended to be statistically non-significant (p > .05). Most FST values computed among groups and subpopulations using Y-chromosome markers were statistically significant. AMOVA confirmed that divergence between cattle groups was only significant for Y-chromosome markers (ΦCT = 0.209). At the mitochondrial level, African sires resembled an undifferentiated population with individuals explaining 94.3% of the total variance. Whatever the markers considered, the highest contributions to total Nei's gene diversity and allelic richness were found in West African cattle. Genetic structuring had no effect on patterns of contributions to diversity.