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A total of 1015 adult cows belonging to nine West African cattle breeds were assessed for 16 body measurements and 18 qualitative traits to ascertain the existence of geographical patterns of variation. Sampling was carried out in 29 different provinces of Mali, Burkina Faso and Benin. For body measurements, taurine breeds took lower average values than the zebu breeds. Sanga cattle took intermediate values. Qualitative traits did not allow to differentiate among cattle groups (taurine, zebu or sanga) or breeds. Principal component analysis identified two factors explaining 56.4 and 9.2 % of the variance for body measurements, respectively. Two correspondence analysis dimensions computed on qualitative traits explained a small proportion of the variability (20.8 and 13.5 %, respectively). Contour plots were constructed using the eigenvalues computed for each individual and either factor or dimension identified; confidence regions calculated confirmed that body measurements clearly differentiated zebu and taurine cattle breeds while qualitative traits did not. Factor 1 was projected on a geographical map, using provinces as nodes, to assess breed-free variation for body measurements. A pattern of continuous variation from the Sahel area southwards was identified. Probably, breeding decisions promoting the crosses between zebu-like and taurine cattle are underlying this geographical pattern of variation. The implementation of selection strategies aiming at the increase of the productivity of native West African taurine cattle breeds while avoiding looses in trypanotolerant ability would be highly advisable.

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.