Serologic survey for selected viral pathogens in free-ranging endangered European mink (Mustela lutreola) and other mustelids from south-western France

To investigate the possible role of selected pathogens in the decline of endangered European mink (Mustela lutreola) populations and the potential for these pathogens to affect mink survival, a serologic survey was conducted using serum samples collected from March 1996 to March 2003 in eight departments of south-western France. In total, 481 free-ranging individuals of five mustelid species (including the European mink) were tested. Sympatric mustelids can serve as sentinels to determine the presence of antibodies to viruses in the study area that could potentially infect mink. Antibodies to Canine distemper virus (CDV) were detected in all species; 9% of 127 European mink, 20% of 210 polecats (Mustela putorius), 5% of 112 American mink (Mustela vison), 33% of 21 stone marten (Martes foina) and 5% of 20 pine marten (Martes martes). Antibody prevalence was significantly higher in stone marten and polecats, possibly because their ranges overlap more closely with that of domestic species than that of the other species tested. Antibodies to Canine adenovirus were detected in all species but the pine marten; antibody prevalence estimates ranging from 2% to 10%. Antibodies to canine parainfluenza virus were detected in 1% of European mink, 1% of American mink and 5% of tested polecats but were not detected in Martes species. Antibodies to Rabies virus (RV) were detected in three animals, possibly because of interspecies transmission of bat lyssaviruses as the sampling area is considered to be free of RV, or to a lack of test specificity, as antibody titers were low. The high antibody prevalence to potentially lethal CDV suggests that this pathogen could have significant effects on the free-ranging populations and has implications for the conservation efforts for the endangered European mink.     

Genetic neighbourhood and effective population size in the endangered European mink <Emphasis Type="Italic">Mustela lutreola</Emphasis>

Genetic neighbourhood and effective population size (N _e) are critical factors when determining the potential survival of threatened species. Carnivores have intrinsically small effective numbers, because, as top predators, they show low densities. The European mink, Mustela lutreola, is one of the most endangered carnivores in the world and has suffered continual decline and local extinctions. The genetic neighbourhood, area within which adults could randomly mate, averaged N _a = 31.7 km diameter, allowing that population size within the neighbourhood area only ranged from N _b = 6.1 to 22.8 animals. Although the population size was assessed in one of the main mink populations in the world, this neighbourhood size is far below the values regarded as critical in literature. However, in contrast with recent propositions, the ratio N _e /N only ranged between 0.09 and 0.19, estimates close to the average recognised by Frankham [(1995) Genetic Research 66: 95–107] for wildlife populations. In the context of the challenge to conserve this endangered carnivore, the studied neighbourhood provided crucial information suggesting both a low neighbourhood size and severe disturbance of breeding exchanges, emphasising the dramatically threatened status of the European mink.     

Novel microsatellite markers for Dalechampia scandens (Euphorbiaceae) and closely related taxa: application to studying a species complex

We developed novel microsatellite markers for D alechampia scandens L. (Euphorbiaceae). The target plants belong to a distinct, but undescribed, species in the D . scandens species complex, characterized by small resin‐producing glands. In total, 110 alleles over 36 novel markers were identified across 39 individuals from three populations. The number of alleles varied from one to seven, with an average of 3.06 ± 0.26 alleles per locus. The developed markers, along with previously developed ones for a large‐glanded D . scandens species, were tested for amplification in 11 additional species of the genus D alechampia. Four markers did not produce any detectable allele in 37 individuals from two populations of the large‐glanded species. Average expected heterozygosity across all small‐ and large‐glanded specific loci was 0.36 and 0.15, for the small and large glanded populations, respectively. Cross‐species amplification showed that 89% of all markers were successfully amplified in at least one of the 11 other D alechampia species. These microsatellite markers may be useful for detecting undescribed species in the D . scandens species complex, and can be used for comparative analyses of genetic structure, mating system and phylogeography of other D alechampia species.     

Microsatellite markers for the endangered Roanoke logperch, Percina rex (Percidae) and their potential utility for other darter species

The Roanoke logperch (Percina rex Jordan and Evermann), an endangered fish, occurs in only six watersheds in the Roanoke and Chowan river drainages of Virginia, USA. The species’ population genetic structure is poorly known. We developed 16 microsatellite markers that were reliably scorable and polymorphic P. rex. Markers were also screened in seven other darter species of the genus Percina. Most markers exhibited successful amplification and polymorphism in several species. These markers may therefore prove useful for population genetic studies in other darters, a diverse but highly imperiled group.     

Microsatellite DNA primers for the endangered vermilion darter,Etheostoma chermocki,and cross‐species amplification in other darters (Percidae: Etheostoma)

The endangered vermilion darter (Etheostoma chermocki) is endemic to the Black Warrior River system in the Mobile Basin in Alabama. Restoration and conservation of this species require an understanding of its population genetic structure, which can be characterized using microsatellite DNA. Nine microsatellite loci were developed; eight loci were polymorphic. Although observed heterozygosity was lower than expected heterozygosity in most polymorphic loci, only one locus showed significant deviation from Hardy–Weinberg equilibrium. These nine markers were tested in an additional 24 species of Etheostoma and appear to have sufficient allelic variation to be useful in studies of population genetic structure.     

The first linkage map of the American mink (Mustela vison)

Described herein, the first microsatellite linkage map for the American mink consists of 85 microsatellite markers resolved into 17 linkage groups. The map was constructed using 92 F(1) progeny from five sire families created by crossing mink with different colour types. The linkage groups ranged from 0 to 137 cM. These linkage groups were assigned to 12 of the 14 mink autosomes using a somatic cell hybrid panel. The total map covered 690 sex-averaged Kosambi units with an average marker spacing of 8 cM. This map will facilitate further genetic mapping of monogenic characters and QTL.     

Nuclear microsatellite DNA markers for New Zealand kiwi (Apteryx spp.)

Kiwi (Apterygidae) is an endemic New Zealand avian family comprising five species whose conservation is actively managed. We present five polymorphic microsatellite DNA loci isolated from North Island brown kiwi (Apteryx mantelli). In addition, we demonstrate cross‐amplification, and in some cases, polymorphism, of these microsatellite DNA loci in four other kiwi species. Therefore, these markers may be broadly applicable to conservation genetic studies within this family.     

Development of 51 genomic microsatellite DNA markers of guppy (Poecilia reticulata) and their application in closely related species

Fifty‐one microsatellite DNA markers of guppy (Poecilia reticulata) were developed. All of the markers detected moderate allelic variation. The number of alleles for each locus ranged from two to 10. Observed and expected heterozygosities varied from 0.10 to 0.63 and from 0.23 to 0.77, respectively. Three additional fish species of family Poeciliidae were used for the cross‐species amplification of these markers. It was found that only four to 16 markers detected polymorphism in these three fish species.     

Microsatellite markers from an expressed sequence tag library of half‐smooth tongue sole (Cynoglossus semilaevis) and their application in other related fish species

Microsatellite markers have been developed from a cDNA library of half‐smooth tongue sole, Cynoglossus semilaevis. Twenty‐five microsatellites were selected for designing microsatellite primers, of which 11 gave working primer pairs. They had between four and 12 alleles. Observed and expected heterozygosities varied from 0.60 to 0.90 and from 0.57 to 0.88, respectively. Five additional fish species assessed for cross‐species amplification revealed between one and four positive amplifications and between 0 and four polymorphic loci per species.     

Bayesian analysis of hybridization and introgression between the endangered european mink (Mustela lutreola) and the polecat (Mustela putorius)

Human-mediated global change will probably increase the rates of natural hybridization and genetic introgression between closely related species, and this will have major implications for conservation of the taxa involved. In this study, we analyse both mitochondrial and nuclear data to characterize ongoing hybridization and genetic introgression between two sympatric sister species of mustelids, the endangered European mink (Mustela lutreola) and the more abundant polecat (M. putorius). A total of 317 European mink, 114 polecats and 15 putative hybrid individuals were collected from different localities in Europe and genotyped with 13 microsatellite nuclear markers. Recently developed Bayesian methods for assigning individuals to populations and identifying admixture proportions were applied to the genetic data. To identify the direction of hybridization, we additionally sequenced mtDNA and Y chromosomes from 78 individuals and 29 males respectively. We found that both hybridization and genetic introgression occurred at low levels (3% and 0.9% respectively) and indicated that hybridization is asymmetric, as only pure polecat males mate with pure European mink females. Furthermore, backcrossing and genetic introgression was detected only from female first-generation (F1) hybrids of European mink to polecats. This latter result implies that Haldane's rule may apply. Our results suggest that hybridization and genetic introgression between the two species should be considered a rather uncommon event. However, the current low densities of European mink might be changing this trend.     

Microsatellite markers for the palaeotropic pioneer tree genus Macaranga (Euphorbiaceae) and their cross‐species transferability

We developed primer sequences for five polymorphic microsatellite loci in the tropical ant‐plant genus Macaranga (Euphorbiaceae). Population genetic parameters were determined on the basis of 30 individuals from each of two Macaranga species in Borneo. Allele numbers per locus ranged from three to 13. Expected and observed heterozygosities ranged from 0.160 to 0.850 and from 0.130 to 0.700, respectively. Four of the five primer pairs cross‐amplify polymorphic PCR products in a wide range of Macaranga species.     

Leptospirosis in free-ranging endangered European mink (Mustela lutreola) and other small carnivores (Mustelidae, Viverridae) from southwestern France

To study the possible role of disease in the decline of endangered European mink (Mustela lutreola), we conducted a survey of antibody prevalence and renal carriage of pathogenic leptospira (Leptospira interrogans sensu lato) using serum and kidney samples collected from 1990 to 2007 from several free-ranging small carnivores and farmed American mink (Mustela vison) in southwestern France. An indirect microscopic agglutination test using a panel of 16 serovars belonging to 6 serogroups (Australis, Autumnalis, Icteroh?morrhagi?, Grippotyphosa, Panama, Sejroe) revealed antibodies in all species, with significant differences in antibody prevalences: 74% in European mink (n=99), 65.4% in European polecats (Mustela putorius, n=133), 86% in American mink (n=74), 89% in stone martens (Martes foina, n=19), 74% in pine martens (Martes martes, n=19), 35% in common genets (Genetta genetta, n=79), and 31% in farmed American mink (n=51). Serogroups Australis and Icteroh?morragi? were dominant in most free-ranging species; serogroup Grippotyphosa had high prevalences in European mink. Such high antibody prevalences have never been reported. They are probably related to the large number of known reservoirs, rats (Rattus spp.), muskrat (Ondatra zibethicus), and coypu (Myocastor coypu), in the study area. The polymerase chain reaction test specific for pathogenic leptospiral DNA detected renal carriage in 23% of 34 European mink, 22% of 18 polecats, and 15% of 33 free-ranging American mink, with no significant differences. Renal carriage shows that mustelids may shed leptospira for short periods, but their epidemiologic role is probably limited. High antibody prevalences suggest that the disease is unlikely to be highly pathogenic for these species; however, chronic forms of the disease (abortions, renal lesions) could reduce the reproductive success or life span of infected animals. Further studies on the pathogenicity of leptospirosis in these populations are needed to measure its impact on the population dynamics of these rodent predators.     

Microsatellite loci for the southern pine beetle (Dendroctonus frontalis) and cross‐species amplification in Dendroctonus

We developed microsatellite loci for the southern pine beetle (Dendroctonus frontalis). Twelve microsatellite loci were identified. Eight loci were polymorphic and sufficiently variable in 62 individuals (expected heterozygosity ranged from 0.707 to 0.880) to investigate population structure. All loci conformed to HWE except Dfr‐14, which showed heterozygote excess, and no two loci deviated from linkage equilibrium. The loci were tested for cross‐species amplification in four species of Dendroctonus (D. valens, D. terebrans, D. brevicomis, and D. ponderosae). Seven loci were polymorphic in at least one of the species tested.     

Microsatellite markers characterized in the barn owl (Tyto alba) and of high utility in other owls (Strigiformes: AVES)

We have identified 15 polymorphic microsatellite loci for the barn owl (Tyto alba), five from testing published owl loci and 10 from testing non‐owl loci, including loci known to be of high utility in passerines and shorebirds. All 15 loci were sequenced in barn owl, and new primer sets were designed for eight loci. The 15 polymorphic loci displayed two to 26 alleles in 56–58 barn owls. When tested in 10 other owl species (n = 1–6 individuals), between four and nine loci were polymorphic per species. These loci are suitable for studies of population structure and parentage in owls.