Mitochondrial genome variation in domesticated sable (Martes zibellina)

The first comparison of mitochondrial variations in sables from captive and natural populations of the Urals, Central Siberia, Yakutia, Kamchatka, and Japan has been performed. The object of comparative analysis was a 427-bp 5' fragment of the mitochondrial control region, including the D-loop. Two main haplogroups of the sable mitochondrial genome have been found, which provides new data for reconstruction of the spread of the sable over its current range. Asymmetry of the haplotype abundances in the captive populations of sables has been detected. The mitochondrial haplotypes characteristic of sable breeds have been identified. The possible role of the frequent mitochondrial haplotypes of the captive population in the sable adaptation to the conditions of captivity is discussed.     

Microsatellite analysis of two captive populations of sable (<Emphasis Type="Italic">Martes zibellina</Emphasis> L.)

The high value of sable (Martes zibellina L.) fur and stable demand for it over the centuries have led to suboptimal hunting patterns and, as a result, considerable fluctuations in the sizes of natural populations of this species. To maintain the traditional export of sable fur, efforts towards commercial domestication of sable have been made in Russia. The first farm population of sable consisted of animal from eight natural populations was founded in 1929. After the problems related to breeding in captivity were solved, directional selection began. Eighty years of breeding have resulted in sable herds with homogeneous quantitative characters. Prospects for further breeding depend on the current level of genetic diversity in the captive populations of sables formed during the first stages of domestication. The sable populations of the Pushkinsky and Saltykovsky fur farms located in Moscow oblast, which were the objects of this study, are the progenitors of the existing captive populations. The first estimation of genetic variation of this species by means of a panel of micro-satellite markers was developed for this study. Two captive sable populations were analyzed using ten micro-satellite loci; a total of 75 alleles were found in both populations. Population-specific alleles were identified (6 and 13 in the Pushkinsky and Saltykovsky populations, respectively). The populations studied were found to be differentiated with respect to four microsatellite loci.     

Microsatellite analysis of two captive populations of sable (Martes zibellina L.)

The high value of sable (Martes zibellina L.) fur and stable demand for it over the centuries have led to suboptimal hunting patterns and, as a result, considerable fluctuations in the sizes of natural populations of this species. To maintain the traditional export of sable fur, efforts towards commercial domestication of sable have been made in Russia. The first farm population of sable consisted of animal from eight natural populations in 1929. After the problems related to breeding in captivity were solved, directional selection began. Eighty years of breeding have resulted in sable herds with homogeneous quantitative characters. Prospects for further breeding depend on the current level of genetic diversity in the captive populations of sables formed during the first stages of domestication. The sable populations of the Pushkinsky and Saltykovsky fur farms located in Moscow oblast, which were the objects of this study, are the progenitors of the existing captive populations. The first estimation of genetic variation of this species by means of a panel of microsatellite markers was developed for this study. Two captive sable populations were analyzed using ten microsatellite loci; a total of 75 alleles were found in both populations. Population-specific alleles were identified (6 and 13 in the Pushkinsky and Saltykovsky populations, respectively). The populations studied were found to be differentiated with respect to four microsatellite loci.     

Genetic structure of the sable <Emphasis Type="Italic">Martes zibellina</Emphasis> L. populations from Magadan oblast as inferred from mitochondrial DNA variation

Restriction polymorphism of the mtDNA cytochrome b gene was studied in nine sable Martes zibellina L. populations from three introduction foci of Khabarovsk and Kamchatka sables in Magadan oblast: Olya, Kolyma, and Omolon. For comparison, similar studies were performed with the populations of central Kamchatka and Khabarovsk krai. In total, 444 DNA specimens were examined. Three mtDNA haplotypes (A, B, and C) proved to occur at various frequencies in the populations under study. The sable population system displayed high differentiation (F _ST = 22.3%). The populations of the Olya focus were most similar genetically to the populations of Kamchatka; those of the Omolon focus were similar to the Khabarovsk populations, and those of the Kolyma focus occupied an intermediate place. The observed spatial heterogeneity of the sable populations of Magadan oblast was explained in terms of the formation of the introduction foci of Kamchatka and Khabarovsk sables, starting from the 1950s.     

Genetic structure of the sable Martes zibellina L. populations from magadan oblast as inferred from mitochondrial DNA variation

Restriction polymorphism of the mtDNA cytochrome b gene was studied in nine sable Martes zibellina L. populations from three introduction foci of Khabarovsk and Kamchatka sables in Magadan oblast: Olya, Kolyma, and Omolon. For comparison, similar studies were performed with the populations of central Kamchatka and Khabarovsk krai. In total, 444 DNA specimens were examined. Three mtDNA haplotypes (A, B, and C) proved to occur at various frequencies in the populations under study. The sable population system displayed high differentiation (FST = 22.3%). The populations of the Olya focus were most similar genetically to the populations of Kamchatka; those of the Omolon focus were similar to the Khabarovsk populations, and those of the Kolyma focus occupied an intermediate place. The observed spatial heterogeneity of the sable populations of Magadan oblast was explained in terms of the formation of the introduction foci of Kamchatka and Khabarovsk sables, starting from the 1950s.     

Genetic analysis of sable (<Emphasis Type="Italic">Martes zibellina</Emphasis>) and pine marten (<Emphasis Type="Italic">M. martes</Emphasis>) populations in sympatric part of distribution area in the northern Urals

Analysis of nucleotide sequences of the mitochondrial DNA (mtDNA) control region (495 bp) of sables (Martes zibellina) and pine martens (M. martes) from allopatric parts of the species ranges has shown a considerable interspecific genetic distance (>3%). In sympatric populations of these species in the northern Urals, differences between two species-specific mtDNA lineages are still large; however, classification of each individual nucleotide sequence with one of the two lineages is not correlated with whether the given animal is phenotypically a sable, a pine marten, or a potential hybrid (the so-called “kidas”). This indicates a high degree of reciprocal introgression of the sable and pine marten mtDNA in the northern Urals and suggests that their interspecific hybridization is common in the sympatric zone.     

Variability of cranial characters in acclimatized sable (<Emphasis Type="Italic">Martes zibellina</Emphasis>) populations

Comparative analysis of metric and nonmetric variations of the sable skull in autochthonous and acclimatized populations was performed. In acclimatized sables, the skull is larger than in sables of the same origin from the Baikal region; however, they are smaller than animals of the autochthonous population. In nonmetric cranial characters, in one case, sables acclimatized in the Ob region are similar to autochthonous animals; in the other, they are similar to sables from the Baikal region. During 40 years after introduction, the population groups of acclimatized sables acquired phenotypic differences from both autochthonous sables dwelling in similar conditions and animals from the Baikal region of the same origin as acclimatizants.     

Genetic individualization of sable (Martes zibellina L. 1758) using microsatellites

Genetic individualization based on non-invasive sampling is crucial for estimating the numbers of individuals in endangered mammalian populations. In sable (Martes zibellina)-poaching cases, identifying the number of animals involved is critical for determining the penalty. In addition, investigating animal numbers for wild sable populations requires genetic individualization when collecting several samples in neighboring regions. Microsatellites have been demonstrated to be reliable markers for individual identification. Thirty-three microsatellite loci derived from Mustelidae were selected to develop a genetic individualization method for sable. Three reference populations containing 54 unrelated sables were used to calculate allele number, allelic frequencies, and the polymorphic information content of each locus. The data were subsequently used to assess the validity of a combination of twelve loci for sable individualization. We defined twelve polymorphic loci that were easy to be amplified and genotyped. Four significant deviations from Hardy-Weinberg equilibrium were observed among the 12?loci in the three populations. The match probability of an individual from the reference populations with a random individual based on the 12?loci was 1.37?×?10^?13. Using the combination of the twelve loci provides sufficient power to individualize sables considering the levels of microsatellite polymorphism observed. These loci were successfully applied to a case of sable poaching and provided valid evidence to determine the penalty. The genetic individualization of sable based on these loci might also be useful to investigate the numbers of animals in wild populations.     

Genetic structure of sable (Martes zibellina L.) in Eurasia—analysis of the mitochondrial lineages distribution

The phylogeography of the sable, which is a commercially valuable species, is extremely complicated and poorly investigated. Specifically, the effects of factors such as the range dynamics of the sable during the Pleistocene Epoch, the localization of glacial refugia, species distribution pattern in Holocene, and recent dramatic population decline, along with massive reacclimatization measures, on the species phylogeography remain unclear. Based on the sequence analysis of the control region of mitochondrial DNA from sables that inhabit different parts of the species range, a suggestion was made of the considerably high Pleistocene genetic diversity in sable, which was subsequently lost. The initial diversity of mitochondrial lineages is mostly preserved in the Urals, while in the eastern part of the range, it seems to have been depleted as early as before the last glacial maximum. On the other hand, the even greater depletion of the mitochondrial lineages observed in some populations of central Siberia can be associated with the dramatic population decline at the turn of the 20th century.     

A PCR-RFLP-based method to distinguish sable (<Emphasis Type="Italic">Martes zibellina</Emphasis>) and pine marten (<Emphasis Type="Italic">Martes martes</Emphasis>)

Species identification is an important issue in conservation and a particular focus for wildlife forensics. Molecular biological methods retain a unique power to differentiate between difficult samples that lack other identifiable characteristics. The pine marten (Martes martes) and sable (Martes zibellina) are closely related species with very similar pelage characteristics and are often difficult to distinguish from each other. The sable, however, in contrast to the pine marten, remains an endangered and protected animal in China with both hunting and fur trade strictly prohibited for this species. Here, we present a polymerase chain reaction-based restriction fragment length polymorphism method for distinguishing the two species. We sequenced a 638-bp fragment of cytochrome b gene in 39 sables, 68 pine martens, and 10 stone martens and identified all variable nucleotides. A new primer pair was subsequently designed to amplify a 316-bp fragment containing restriction sites of enzyme BseG I and BamH I that are different among martens. When the fragment was cut using BseG I, the resulting restriction pattern was identical in the sable and pine marten, but differed from all other martens. When cut using BamH I, the fragment generated two diagnostic fragments in the sable which could distinguish them from pine martens. This method was valid for all haplotypes of sable and pine marten thus far identified and has high potentially applicability for the identification of the two species.     

Genetic Effects of Sable (<Emphasis Type="Italic">Martes zibellina</Emphasis> L.) Reintroduction in Western Siberia

In the middle of the 20th century, massive introductions of sables were performed to recover the area of this valuable fur species. In this work, genetic variation of a naturalized sable population from the Vakh River basin (Nizhnevartovskiy district, Khanty-Mansi Autonomous Okrug) was investigated. This population developed as a result of sable introduction from Cisbaikalia in 1952?1957. The naturalized sable population of the Vakh basin occupies an intermediate position between two autochthonous sable populations from the Ob River area and Cisbaikalia, as assessed by variation of five microsatellite loci. Apparently, the genetic structure of the modern sable population from the Vakh basin was formed by mixing the gene pools of the original Cisbaikalian population and the neighboring autochthonous populations from the Ob River area which recovered their numbers in a natural way. Data on genetic variation in the naturalized sable population agree with the results of previous morphological studies and can be employed for long-term monitoring of the outcome of sable introduction.     

Genetic diversity and conservation units in wild and captive populations of endangered freshwater fishes: a case of <Emphasis Type="Italic">Hemigrammocypris rasborella</Emphasis> in Shizuoka,Japan

Population structure and genetic diversity were examined using partial mitochondrial cytochrome b gene sequences of four wild, one reintroduced, and five captive populations of the endangered cyprinid Hemigrammocypris rasborella from three river systems in the easternmost region of the species’ range in Shizuoka Prefecture, central Honshu, Japan. We detected loss of genetic diversity from portions of the wild and captive populations, as well as suspected nonindigenous haplotypes in some captive, reintroduced, and even wild populations. Given the population structure revealed, we suggest that the populations should be managed with consideration for both the endemism and viability (avoidance of inbreeding depression) of the local populations.     

陕西省林麝mtDNA D-loop区序列结构和种群遗传多样性

林麝(Moschus berezovskii)曾广泛分布于中国,由于盗猎和栖息地缩小,秦岭地区野生种群数量迅速下降,圈养繁殖种群已成立了几十年,但大多数圈养种群的遗传背景不清,种群规模增长非常缓慢。为了给这一物种的保护和管理提供有用的信息,调查了陕西省林麝1个圈养种群3个野生种群线粒体DNA(mt DNA)D-Loop 632 bp片段的遗传多样性和种群结构。在69个个体中其碱基组成为A+T的平均含量63.2%高于G+C含量36.8%,共检测到变异位点171个(约占总位点数的27.05%)。核苷酸多样性(Pi)为0.04424,平均核苷酸差异数(K)为19.908。69个个体分属32个单倍型,单倍型间的平均遗传距离(P)为0.070。32个单倍型构建的NJ系统树聚为3个分支,4个林麝群体中的单倍型是随机分布的。4个群体的平均遗传距离为0.043(标准误SE为0.005),凤县养殖场群体与留坝和陇县群体的亲缘关系较远。单倍型间的平均遗传距离为0.043,可见其遗传分化尚未达到种群分化的水平。结果表明,陕西省林麝群体mt DNA D-loop区序列存在着较丰富的变异和遗传多样性,凤县野生群体和凤县养殖场群体的核苷酸多样性和单倍型多样较高,养殖场种群没有出现近亲繁殖及遗传多样性下降的情况。凤县野生群体和凤县养殖场群体两者遗传分化较小,存在着较高的基因流水平。     

Genetic rescue of an inbred captive population of the critically endangered Puerto Rican crested toad (<Emphasis Type="Italic">Peltophryne lemur</Emphasis>) by mixing lineages

The Puerto Rican crested toad (Peltophryne lemur) is currently composed of a single wild population on the south coast of Puerto Rico and two captive populations founded by animals from the northern and southern coasts. The main factors contributing to its decline are habitat loss, inundation of breeding ponds during storms, and impacts of invasive species. Recovery efforts have been extensive, involving captive breeding and reintroductions, habitat restoration, construction of breeding ponds, and public education. To guide future conservation efforts, genetic variation and differentiation were assessed for the two captive colonies and the remaining wild population using the mitochondrial control region and six novel microsatellite loci. Only two moderately divergent mitochondrial haplotypes were found, with one fixed in each of the southern and northern lineages. Moderate genetic variation exists for microsatellite loci in all three groups. The captive southern population has not diverged substantially from the wild population at microsatellite loci (F _ST = 0.03), whereas there is little allelic overlap between the northern and southern lineages at five of six loci (F _ST > 0.3). Despite this differentiation, they are no more divergent than many populations of other amphibian species. As the northern breeding colony may not remain viable due to its small size and inbred nature, it is recommended that a third breeding colony be established in which northern and southern individuals are combined. This will preserve any northern adaptive traits that may exist, and provide animals for release in the event that the pure northern lineage becomes extirpated.     

Phylogeography of sable (Martes zibellina L. 1758) in the southeast portion of its range based on mitochondrial DNA variation: highlighting the evolutionary history of the sable

To reveal phylogeographic features of sable (Martes zibellina) in the southeast part of its range, we analyzed variability of the mitochondrial DNA (mtDNA) cytochrome b gene, tRNA (Pro), tRNA (Thr) and control region (D-loop) sequences from 78 specimens in populations of the Russian Far East, northeast China, and Mongolia. Our results revealed the presence of 49 different haplotypes split into two major phylogenetic groups—clades A and B, the latter separated into two clades, B1 and B2. Comparative analysis of D-loop haplotypes in populations originating from the southeast (Russian Far East, China and Mongolia) and the west (northern Urals) portions of sable range indicated that all three mtDNA clades were present in different regional groups. However, highest diversity of clade B1 in northeast China and its nearly complete absence from the Urals suggest that the southeast sable range, being a refuge during Pleistocene glacial periods, can be considered the center of genetic diversification and possibly origin of this species. All divergence estimates fall within the Pleistocene suggesting that Quarternary glaciations played an important role in phylogeographic differentiation of sable.     

Adaptations to fasting in a terrestrial mustelid, the sable (Martes zibellina)

The aim of this study was to investigate whether the actively wintering Palearctic sable Martes zibellina has evolved physiological adaptations to tolerate nutritional scarcity. Sixteen farm-bred male sables were divided into a fed control group and an experimental group fasted for 4 days. The rate of weight loss in the sable was similar to other medium-sized mustelids. Fasting led to hypoglycaemia and to a decreased lymphocyte percentage. The sable derived metabolic energy from both subcutaneous and intraabdominal white adipose tissues and the relative decrease in fat mass was the largest for the retroperitoneal and subcutaneous depots. Metabolic energy derived partly from body proteins indicated by the increased plasma levels of urea, uric acid and total essential amino acids. Triacylglycerols accumulated in the livers of the fasted sables and the increased plasma aminotransferase activities suggested hepatic dysfunction. The decreased plasma insulin concentrations and the elevated cortisol levels probably contributed to stimulated lipolysis and protein catabolism. Moreover, fasting increased the plasma ghrelin concentrations of the sables and down-regulated the thyroid activity.     

Lineage identification of Galápagos tortoises in captivity worldwide

Ex situ conservation strategies may be substantially informed by genetic data, and yet only recently have such approaches been used to facilitate captive population management of endangered species. The Galápagos tortoise Geochelone nigra is an endangered species that has benefited greatly from the application of molecular and population genetic data, but remains vulnerable throughout its range. The geographic and evolutionary origins of 98 tortoises in private collections and zoos on three continents were identified using mitochondrial DNA (mtDNA) control region sequences and multi-locus microsatellite genotype data relative to a large database of representative samplings from all extant populations, including historical population allele frequency data for the Geochelone nigra abingdoni taxon on Pinta by way of museum specimens. All but six individuals had mtDNA haplotypes previously sampled, with the novel haplotypes identified as most closely related to robust populations on the islands of Santa Cruz and Isabela. Multi-locus genotypic assignments corroborated the results obtained from the mtDNA analyses, with 83.7% of individuals consistently assigned to the same locality by both datasets. Overall, the majority of captive unknowns sampled were assigned to the La Caseta Geochelone nigra porteri population, with no fewer than six individuals of hybrid origin detected. Although a purported Pinta individual was revealed to be of Pinzón ancestry, the two females currently housed with Lonesome George exhibited haplotypic and genotypic signatures that indicate that they are among the most appropriate matches for captive breeding. More generally, molecular approaches continue to represent important tools for assessing conservation value, minimizing hybridization and guiding management programs for preserving the distinctiveness of G. nigra taxa in captivity.     

Effect of coat color mutations on behavioral polymorphism in farm populations of American minks (<Emphasis Type="Italic">Mustela vison</Emphasis> Schreber, 1777) and sables (<Emphasis Type="Italic">Martes zibellina</Emphasis> Linnaeus, 1758)

Behavioral polymorphism estimated by the expression of the defensive reaction towards humans has been studied in farm-bred American minks and sables with different color types. Most animals (both minks and sables) from farm populations displayed passive defensive behavior towards humans in the standard hand catch test. Coat color genes have been found to have pleiotropic effects; they influence both the penetrance and expressivity of domestication behavior: in animals with aberrant color types (both sapphire minks and white-and-black sables), the proportion of animals with domestication behavior and the expressivity of this behavior are significantly higher (p < 0.01 and p < 0.001, respectively).     

The Genetic Integrity of the Ex Situ Population of the European Wildcat (Felis silvestris silvestris) Is Seriously Threatened by Introgression from Domestic Cats (Felis silvestris catus)

Studies on the genetic diversity and relatedness of zoo populations are crucial for implementing successful breeding programmes. The European wildcat, Felis s. silvestris, is subject to intensive conservation measures, including captive breeding and reintroduction. We here present the first systematic genetic analysis of the captive population of Felis s. silvestris in comparison with a natural wild population. We used microsatellites and mtDNA sequencing to assess genetic diversity, structure and integrity of the ex situ population. Our results show that the ex situ population of the European wildcat is highly structured and that it has a higher genetic diversity than the studied wild population. Some genetic clusters matched the breeding lines of certain zoos or groups of zoos that often exchanged individuals. Two mitochondrial haplotype groups were detected in the in situ populations, one of which was closely related to the most common haplotype found in domestic cats, suggesting past introgression in the wild. Although native haplotypes were also found in the captive population, the majority (68%) of captive individuals shared a common mtDNA haplotype with the domestic cat (Felis s. catus). Only six captive individuals (7.7%) were assigned as wildcats in the STRUCTURE analysis (at K = 2), two of which had domestic cat mtDNA haplotypes and only two captive individuals were assigned as purebred wildcats by NewHybrids. These results suggest that the high genetic diversity of the captive population has been caused by admixture with domestic cats. Therefore, the captive population cannot be recommended for further breeding and reintroduction.