In species of great conservation concern, special attention must be paid to their phylogeography, in particular the origin of animals for captive breeding and reintroduction. The endangered European mink lives now in at least three well-separated populations in northeast, southeast and west Europe. Our aim is to assess the genetic structure of these populations to identify 'distinct population segments' (DPS) and advise captive breeding programmes. First, the mtDNA control region was completely sequenced in 176 minks and 10 polecats. The analysis revealed that the western population is characterized by a single mtDNA haplotype that is closely related to those in eastern regions but nevertheless, not found there to date. The northeast European animals are much more variable (pi = 0.012, h = 0.939), with the southeast samples intermediate (pi = 0.0012, h = 0.469). Second, 155 European mink were genotyped using six microsatellites. The latter display the same trends of genetic diversity among regions as mtDNA [gene diversity and allelic richness highest in northeast Europe (H(E) = 0.539, R(S) = 3.76), lowest in west Europe (H(E) = 0.379, R(S) = 2.12)], and provide evidences that the southeast and possibly the west populations have undergone a recent bottleneck. Our results indicate that the western population derives from a few animals which recently colonized this region, possibly after a human introduction. Microsatellite data also reveal that isolation by distance occurs in the western population, causing some inbreeding because related individuals mate. As genetic data indicate that the three populations have not undergone independent evolutionary histories for long (no phylogeographical structure), they should not be considered as distinct DPS. In conclusion, the captive breeding programme should use animals from different parts of the species' present distribution area.
The aim of this work was to assess the efficiency of dissuasive spreading of maize to reduce the level of wild boar damage to vines in a Mediterranean area (Pue´chabon, southern France). The 50 wine growers of Pue´chabon were all questioned about the annual losses caused by the wild boar in each vineyard of the study area between 1990 and 1992. We also studied the distribution of the damage on a smaller scale, by mapping the damaged vines within two vineyards. In summer 1993, we distributed 4.7 tons of maize in the woods , and then questioned the wine growers about the losses in each vineyard for 1993. During 1990-1992, on both large and small scales, the damage had a patchy distribution, with more patches of damage occurring close to the woods. Moreover, the later the vines ripened, the less frequent the damage. The severity of the damage was only affected by the distance of the vineyard from woods. In total, the wild boar consumed 20,049 kg of grapes each year between 1990-1992 (193 kg/ha), and 63% of the vineyards were damaged. In 1993, both the density and the compensation paid in the de´partement increased threefold. However, in our study area, both the proportion of damaged vineyards (36%) and the level of damage in the vineyards (151 kg/ha) were reduced, saving more than 60% in compensation. The dissuasive spreading of maize is therefore an efficient tool to reduce the level of damage to vineyards.
Owing to the rapid decline of the European mink (Mustela lutreola) in France, a national conservation action plan has been initiated, in which scientific research to improve understanding of the causes of the decline is one of the primary objectives. In order to investigate the possible role of Aleutian disease parvovirus (ADV) in decline of the species, a serologic survey was conducted from March 1996 to March 2002 in 420 free-ranging individuals of six species of small carnivores distributed in eight dé partements of southwestern France. Antibodies to ADV were detected in 17 of 75 American mink (Mustela vison), 12 of 99 European mink, 16 of 145 polecats (Mustela putorius), four of 17 stone martens (Martes foina), one of 16 pine martens (Martes martes), and three of 68 common genets (Genetta genetta). Seroprevalence was significantly higher in American mink than in other species. Seropositive individuals with gamma globulin levels Ͼ20% were observed in four European mink, four American mink, two stone martens, and one pine marten. Geographic distribution of positive animals indicates the virus has spread to all areas where European mink are found. Furthermore, a trend of increasing prevalence seems to appear in Mustela sp. sympatric with American mink. Although further investigations are necessary to evaluate the role of ADV in decline of European mink, evidence of the virus in the wild at the levels found in our study has implications for conservation of this species.
Eurasian otter populations strongly declined and partially disappeared due to global and local causes (habitat destruction, water pollution, human persecution) in parts of their continental range. Conservation strategies, based on reintroduction projects or restoration of dispersal corridors, should rely on sound knowledge of the historical or recent consequences of population genetic structuring. Here we present the results of a survey performed on 616 samples, collected from 19 European countries, genotyped at the mtDNA control-region and 11 autosomal microsatellites. The mtDNA variability was low (nucleotide diversity = 0.0014; average number of pairwise differences = 2.25), suggesting that extant otter mtDNA lineages originated recently. A star-shaped mtDNA network did not allow outlining any phylogeographic inference. Microsatellites were only moderately variable (H o = 0.50; H e = 0.58, on average across populations), the average allele number was low (observed A o = 4.9, range 2.5-6.8; effective A e = 2.8; range 1.6-3.7), suggesting small historical effective population size. Extant otters likely originated from the expansion of a single refugial population. Bayesian clustering and landscape genetic analyses however indicate that local populations are genetically differentiated, perhaps as consequence of post-glacial demographic fluctuations and recent isolation. These results delineate a framework that should be used for implementing conservation programs in Europe, particularly if they are based on the reintroduction of wild or captive-reproduced otters.
Ultrastructure of spermiogenesis and the main characters of the mature spermatozoon of Troglotrema acutum are described by means of transmission electron microscopy. Specimens were obtained from the nasolacrimal sinuses of an American mink (Mustela vison). Spermiogenesis in T. acutum follows the general pattern of digeneans. The zone of differentiation is a conical-shaped area bordered by cortical microtubules and delimited at its base by a ring of arched membranes. This area contains 2 centrioles associated with striated rootlets and an intercentriolar body between them. The centrioles develop 2 free flagella that grow ortogonally to the median cytoplasmic process. The posterior flagellar rotation and proximodistal fusion of the free flagella with the median cytoplasmic process originate the spermatozoon. The mature spermatozoon of T. acutum is characterized by the presence of 2 axonemes of different lengths presenting the 9+'1' trepaxonematan pattern, 2 bundles of parallel cortical microtubules, 2 mitochondria, a nucleus, and granules of glycogen. These ultrastructural characters are compared with other digenean species previously studied and the importance of different spermatological features is discussed.
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