SummaryThe aim of this work is to highlight the need of monitoring small populations to conserve their genetic variability by using a set of parameters to characterize both the structure of populations and management practices. As a representative example we analyse the pedigree information of the endangered Xalda sheep breed of Asturias. The herdbook of Xalda sheep included a total of 805 animals and 62 herds. The number of founders was 329. Nowadays, there are 562 live animals and 26 active herds. The breed is in risk of losing genetic diversity because of the abusive use of certain individuals as parents. The effective number of founder animals is 81.1. The effective number of founder herds is 9.9. The average value of inbreeding in the whole Xalda population was 1.5%. The average relatedness (AR) coefficient reached 1.8% in the whole pedigree. The genetic representation of the lines of founders is unbalanced. Inbreeding trends and effective size do not provide realistic information concerning the risk of loss of diversity as a result of the shallowness of the genealogical information. We suggest the monitoring of the breed using AR to unbalance the genetic contributions of specific individuals, equalizing the genetic representation of the founders and lines in the population. In addition, AR can suggest the introduction of new, under-represented animals in herds showing high average AR values relative to the population. Our results can be useful to improve the development of conservation initiatives involving open herdbooks to avoid the risk of loss of genetic diversity caused by incorrect management practices. Zusammenfassung

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Five cattle Y-specific microsatellites, totalling six loci, were selected from a set of 44 markers and genotyped on 608 Bos taurus males belonging to 45 cattle populations from Europe and Africa. A total of 38 haplotypes were identified. Haplogroups (Y1 and Y2) previously defined using single nucleotide polymorphisms did not share haplotypes. Nine of the 27 Y2-haplotypes were only present in African cattle. Network and correspondence analyses showed that this African-specific subfamily clustered separately from the main Y2-subfamily and the Y1 haplotypes. Within-breed genetic variability was generally low, with most breeds (78%) showing haplotypes belonging to a single haplogroup. AMOVA analysis showed that partitioning of genetic variation among breeds can be mainly explained by their geographical and haplogroup assignment. Between-breed genetic variability summarized via Principal Component Analysis allowed the identification of three principal components explaining 94.2% of the available information. Projection of principal components on geographical maps illustrated that cattle populations located in mainland Europe, the three European Peninsulas and Mediterranean Africa presented similar genetic variation, whereas those breeds from Atlantic Europe and British Islands (mainly carrying Y1 haplotypes) and those from Sub-Saharan Africa (belonging to Y2-haplogroup) showed genetic variation of a different origin. Our study confirmed the existence of two large Y-chromosome lineages (Y1 and Y2) in taurine cattle. However, Y-specific microsatellites increased analytical resolution and allowed at least two different Y2-haplotypic subfamilies to be distinguished, one of them restricted to the African continent.

Here we study 109 Iberian roe deer individuals corresponding to 9 Spanish populations. Individuals were sampled at locations that are expected to have acted as refugia for the species during the 20th century. Samples were analyzed for a 436 bp mtDNA fragment from the HVI region of mitochondrial DNA and 10 microsatellites. The 109 sequences gave 31 different haplotypes that enabled identification of a new haplogroup (mainly present in Northwestern Iberian populations and representing roughly a third of our samples) that is not present in other European roe deer populations. Using microsatellites, correspondence analysis and molecular coancestry information revealed high molecular differentiation among Northwestern and Central-Southern Spain roe deer populations. Both sequence and microsatellite analysis reveal that the Spanish roe deer populations are genetically heterogeneous and have high genetic structure clearly separating the Pyrenean-reintroduced populations and two main areas for the species in Spain (Northwestern and Central-Southern) coinciding with the two main areas acting as refugia for the majority of the mammal species during glaciations. The implications of the obtained information as regards the phylogeography of the species are discussed together with suggestions as to appropriate strategies for the conservation and management of populations.