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The study aimed to evaluate the comparative anatomy of the liver and intrahepatic branching of the portal vein of the Eurasian otter (Lutra lutra) and the American mink (Neovison vison). Due to their highly valuable fur, minks have expanded their range to many parts of Europe and become available for many biomedical studies. In this study, ten adult minks and five otters were used. The intrahepatic branching of the portal vein was studied by the combined injection and dissection technique. The macroscopic anatomy of the liver revealed that both species have six-lobed livers, although differences in shape, size and some additional fissures were documented. The portal vein, upon entering the liver, divides into the right and left branches. The branching pattern in otters had an additional branch at this level with a caudate process branch. The right branch of the portal vein ramified in the right lateral lobe and the caudate process in the mink livers, while the right branch in the otter livers only distributed functional blood to the right lateral lobe. The larger left portal branch, with its transverse and umbilical parts, ramified in the left liver portion, along with the quadrate, right medial lobe and papillary process.

Angiotensin converting enzyme 2 (ACE2) is a host cell membrane protein (receptor) that mediates the binding of coronavirus, most notably SARS coronaviruses in the respiratory and gastrointestinal tracts. Although SARS-CoV-2 infection is mainly confined to humans, there have been numerous incidents of spillback (reverse zoonoses) to domestic and captive animals. An absence of information on the spatial distribution of ACE2 in animal tissues limits our understanding of host species susceptibility. Here, we describe the distribution of ACE2 using immunohistochemistry (IHC) on histological sections derived from carnivores, ungulates, primates and chiroptera. Comparison of mink (Neovison vison) and ferret (Mustela putorius furo) respiratory tracts showed substantial differences, demonstrating that ACE2 is present in the lower respiratory tract of mink but not ferrets. The presence of ACE2 in the respiratory tract in some species was much more restricted as indicated by limited immunolabelling in the nasal turbinate, trachea and lungs of cats (Felis catus) and only the nasal turbinate in the golden Syrian hamster (Mesocricetus auratus). In the lungs of other species, ACE2 could be detected on the bronchiolar epithelium of the sheep (Ovis aries), cattle (Bos taurus), European badger (Meles meles), cheetah (Acinonyx jubatus), tiger and lion (Panthera spp.). In addition, ACE2 was present in the nasal mucosa epithelium of the serotine bat (Eptesicus serotinus) but not in pig (Sus scrofa domestica), cattle or sheep. In the intestine, ACE2 immunolabelling was seen on the microvillus of enterocytes (surface of intestine) across various taxa. These results provide anatomical evidence of ACE2expression in a number of species which will enable further understanding of host susceptibility and tissue tropism of ACE2 receptor-mediated viral infection

Made available in DSpace on 2022-04-28T19:45:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 Consejo Nacional de Investigaciones Científicas y Técnicas Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Natural Environment Research Council Formulating effective management plans for addressing the impacts of invasive non-native species (INNS) requires the definition of clear priorities and tangible targets, and the recognition of the plurality of societal values assigned to these species. These tasks require a multi-disciplinary approach and the involvement of stakeholders. Here, we describe procedures to integrate multiple sources of information to formulate management priorities, targets, and high-level actions for the management of INNS. We follow five good-practice criteria: justified, evidence-informed, actionable, quantifiable, and flexible. We used expert knowledge methods to compile 17 lists of ecological, social, and economic impacts of lodgepole pines (Pinus contorta) and American mink (Neovison vison) in Chile and Argentina, the privet (Ligustrum lucidum) in Argentina, the yellow-jacket wasp (Vespula germanica) in Chile, and grasses (Urochloa brizantha and Urochloa decumbens) in Brazil. INNS plants caused a greater number of impacts than INNS animals, although more socio-economic impacts were listed for INNS animals than for plants. These impacts were ranked according to their magnitude and level of confidence on the information used for the ranking to prioritise impacts and assign them one of four high-level actions—do nothing, monitor, research, and immediate active management. We showed that it is possible to formulate management priorities, targets, and high-level actions for a variety of INNS and with variable levels of available information. This is vital in a world where the problems caused by INNS continue to increase, and there is a parallel growth in the implementation of management plans to deal with them. School of Biological Sciences University of Aberdeen Instituto de Investigaciones Marinas y Costeras (IIMyC) FCEyN-Universidad Nacional de Mar del Plata-CONICET CC 1260 Instituto de Geología de Costas y del Cuaternario (IGCyC) FCEyN-Universidad Nacional de Mar del Plata-CIC Funes 3350 Instituto de Ecología Regional (IER UNT CONICET) and Facultad de Ciencias Naturales e IMl UNT Residencia Universitaria de Horco Molle, Yerba Buena Business School University of Aberdeen Business School University of Stellenbosch, PO Box 610 Laboratorio de Estudios del Antropoceno (LEA) Facultad de Ciencias Forestales Universidad de Concepción Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)-Dirección Regional Patagonia Norte de la Administración de Parques Nacionales, O’Connor 1188, 8400-San Carlos de Bariloche Laboratorio de Invasiones Biológicas (LIB) Facultad de Ciencias Forestales Universidad de Concepción Institute of Ecology and Biodiversity (IEB) Servicio Agrícola y Ganadero Gobierno de Chile Lab of Vegetation Ecology Instituto de Biociências Universidade Estadual Paulista (UNESP), Av. 24A Centro de Humedales Río Cruces (CEHUM) Universidad Austral de Chile Grupo de Ecología de Invasiones INIBIOMA CONICET Universidad Nacional del Comahue, Quintral 1250 Department of Biology and Biochemistry University of Houston Programa Patagonia Departamento de Conservación de Aves Argentinas/Asociación Ornitológica del Plata Departamento de Análisis de Sistemas Complejos Fundación Bariloche CONICET, Av. Bustillo 9400 EDGE of Existence-Zoological Society of London Lab of Vegetation Ecology Instituto de Biociências Universidade Estadual Paulista (UNESP), Av. 24A Consejo Nacional de Investigaciones Científicas y Técnicas: -2019-74-APN-DIR#CONICET FAPESP: 2018/14995-8 Natural Environment Research Council: NE/S011641/1

The distribution of the American mink in the wild, originating either from accidental escapes or intentional releases from fur farms, was mapped for the first time in Greece, based on opportunistic data collected from 2010 to 2020. Greece is a key actor in Europe’s fur industry, with most mink farms operating in the northwest. Massive intentional releases by activists took place in the late 2000s, while accidental escapes regularly occur. Most mink were recorded in the Region of Western Macedonia, in NW Greece, within and around the core areas of fur farms, where feral populations became established. Animals were also found further south in the Regions of Thessaly (central Greece) and Central Macedonia (northern Greece). Half of mink records were close to protected areas and almost two-thirds near to watercourses. Many animals were away from the water and on high altitudes, with theoretically less favourable conditions for their survival. We also examine possible directions of further mink range expansion in Greece and neighbouring countries through the river network. Mink invasion progress in Greece is little known, thus, the subject is in urgent need of study, as mink is the alien mammal with the highest impact on the European native fauna.

A well-studied predator–prey relationship between American mink (Neovison vison (Schreber, 1777); formerly known as Mustela vison Schreber, 1777) and muskrats (Ondatra zibethicus (Linnaeus, 1766)) in Canada has advanced our understanding of population cycles including the influence of density dependence and lagged responses of predators to prey abundances. However, it is unclear if patterns observed in Canada extend across the southern half of their native range. We used data from the United States to create a 41-year time series of mink and muskrat harvest reports (1970–2011) for 36 states. After controlling for pelt-price effects, we used second-order autoregressive and Lomb–Scargle spectral density models to identify the presence and periodicity of muskrat population cycles. Additionally, we tested for evidence of delayed or direct density dependence and for predator-driven population dynamics. Our results suggest muskrat populations may cycle in parts of the United States; however, results varied by modeling approaches with Lomb–Scargle analyses providing more precise parameter estimates. Observed cycle lengths were longer than expected with weak amplitudes and we urge caution when interpreting these results. We did not detect evidence of a predator–prey relationship driven by a lagged numerical response of American mink. American mink and muskrat fur returns were largely correlated across the region suggesting extraneous factors likely synchronize both populations.

Salt marsh is a unique and biologically productive ecosystem characterized by relatively few endemic terrestrial vertebrates. Salt marsh continues to decline worldwide and the persistence of species restricted to salt marsh may depend on understanding characteristics associated with their use of these ecosystems. Atlantic salt marsh mink (Neovison vison lutensis) were historically found throughout Northeastern Florida (USA) but their numbers and distribution may have declined following coastal development beginning in the 1800s. Information on their current distribution and ecology in Florida is unknown but they are suspected of being restricted to salt marsh. Between 2013 and 2015, we conducted camera surveys for mink in 42.1 km2 units in salt marsh to determine their occupancy, extent of occurrence, and drivers of habitat use. We measured 20 site-specific environmental covariates to model occupancy and detectability. Mink were detected in a 226 km2 area within 14 km of the Atlantic coast between two of the region’s major rivers. We found positive associations in our top overall occupancy model between mink and blue crab (Callinectes sapidus) biomass and between detectability and low marsh dominated by cordgrass (Spartina alterniflora). Our detection data provides further support that mink may be endemic to coastal salt marsh in Florida and that they currently occupy approximately half the northern portion of their historical distribution. We suggest that the long-term persistence of Atlantic salt marsh mink in Florida may depend on the presence of healthy and functional low marsh where aquatic food resources, particularly blue crab, are locally abundant.

This work aims to establish a simplified genotype for American mink (Neovison vison), on the basis of a group of basic genes (Asip, Tyrp–1, Tyr, Myo–5a, and Mc–1r) and three modifying genes (fawn, Ednrb, and Kit). The analysis used pedigrees of 61 females of standard brown, palomino, and silverblue colour variations. The database covered 380 offspring in nine colour variations: brown, silverblue, palomino, brown cross, palomino cross, pearl, pastel, silverpastel, and white. The analysis led to a simplified genotype explaining the principles of inheritance of most common coat colour variations in Polish mink farms. Due to the limited number of animals and the limited number of colour variations used, the analysis could not test the inheritance of all colours found in mink. The genotype was constructed on the basis of the homologous genes responsible for coat colour found in most animal species.

Parasites may negatively affect hosts condition, especially when infection intensity is high. Species introduced to a new habitat are often less exposed to a parasite pressure but may accumulate parasites in time. American mink (Neovison vison) introduced to Europe, Asia, and South America is an example of such invasive species. We analysed nematode prevalence and digestive tract infection intensity in 796 feral American mink from Poland. The analyses were performed separately for stomach, duodenum, small intestine and large intestine. Parasite species identification was performed using molecular methods based on highly conserved nuclear 18S rRNA gene and supplemented with morphological analysis. In total, we collected 26,852 nematodes and 98.6% of them were isolated from mink stomachs. We found positive association between infection intensity in stomach and other parts of digestive tract. Nematode prevalence was estimated at 63.8% and average infection intensity per one American mink at 52.9 (range from 1 to 1118). If the stomach results were theoretically and intentionally omitted the prevalence was 5 times lower (12.7%) and infection intensity 14 times lower (3.7; range 1–50). We identified two nematode species in digestive tracts of American mink: Aonchotheca putorii and Molineus patens. The 18S rRNA gene sequence of Molineus patens has been reported for the first time. The results showed that Aonchotheca putorii is a dominating nematode in the invasive American mink and that it inhabits stomach intensively and preferably.

Mink urinary tract disease (MUTD) often presents as urolithiasis and/or cystitis and is known as an important cause of mortality in mink kits during the early growth season. Antimicrobial flock treatment has been routinely applied as preventive/therapeutic protocol on Danish mink farms with increased mortality associated with MUTD. The therapeutic effect of this treatment strategy has not previously been investigated. In this study, we applied controlled parallel group treatment trials to assess the effect of sulfadiazine/trimethoprim and amoxicillin treatment on mortality associated with MUTD in mink kits. On farm A, eight mink kits were diagnosed with MUTD post mortem in the treatment group (n = 1920, sulfadiazine/trimethoprim treatment: 30 mg/kg, q 24 h, P.O for 5 days) compared to 16 in the untreated control group (n = 1920). No significant difference in mortality associated with MUTD were found between the treatment and the control group using the Fisher’s exact test (P = 0.15). Treatment group 2 (n = 1920, amoxicillin treatment: 14 mg/kg q 24 h, P.O for 5 days) and treatment group 3 (n = 2088, amoxicillin treatment: 7.5 mg/kg q 24 h, P.O for 5 days) were investigated on farm B. Eight and four mink kits were diagnosed with MUTD post mortem in group 2 and 3, respectively. No difference between occurrence of MUTD were found between the control group and treatment group 2 (P = 0.42) or treatment group 3 (P = 0.75). No significant difference between final body weights or weight gain were found between treatment and control weighing groups on farm A or B. In conclusion, antimicrobial treatment administered in the feed showed no significant effect on weight gain or mortality associated with MUTD on the farms included in this study.

The study was aimed to evaluate a possible effect of body condition of female farmed mink (Neovison vison) at the moment of conception on their prospective reproduction and behavior. 601 Perl mink females at age 1 and 2 years were assigned to one of five groups according to their body condition. The following parameters were analyzed: gestation and diapause lengths, litter size, live-born litter size, number of weaned per litter, female barrenness, and the incidence of fur-chewing. The effect of body condition was more pronounced in yearling females, where the largest litters, the highest number of live-born per litter, and the highest weaning success were found in the group with the ideal body condition. In both age groups, the shortest pregnancies and diapause periods were observed in the thinnest females. Fur-chewing was most often noticed in either the thinnest or the most obese animals; females of these groups also exhibited the highest rates of barrenness. Consequently, the lowest incidence of fur-chewing, female barrenness were found in females with ideal body condition.

The aim of the study was to estimate the values of metric traits of selected mink heart veins of standard and mutation colour variants. The study was conducted on 342 hearts of seven-month-old males and 405 hearts of seven-month-old females. Mink colour, resulting from mutation or from crossbreeding mutational colour variants with each other. Metric traits of the coronary sinus, great cardiac vein, middle cardiac vein, posterior vein, and small cardiac vein were determined by photographic recording of the sub-epicardial picture of these vessels after filling them with a water-dilutable dye for acrylic paints together with a 30% food gelatin solution. In addition, the number of the veins forming the great cardiac vein and that of the posterior veins of the left ventricle were determined. Based on the measurement of the width and length of the mink hearts, the heart shape was determined. Differences were found between the traits of the mink heart vessels of standard and mutational colour variants, but they did not allow to formulate clearly the thesis about the effect of mutations on these traits.

Enterocytozoon bieneusi is a zoonotic pathogen that infects a variety of hosts including humans, livestock, wildlife, companion animals, and birds, as well as being abundant in the environment. Humans and nonhuman animals could be infected with E. bieneusi via consumption of food or water that contains zoonotic and host-adapted genotypes. In this study, 288 fecal specimens were collected from farmed minks, blue foxes, and raccoon dogs, in Xinjiang, China. Enterocytozoon bieneusi was examined by PCR amplification based on sequence analysis of the internal transcribed spacer (ITS) region. The overall infection rate of E. bieneusi was 4.9% (14/288), with mink samples showing the highest infection rate (5.6%, 12/214), followed by blue foxes (2.9%, 1/35), and then raccoon dogs (2.6%, 1/39). Six E. bieneusi genotypes were identified, including D (n = 5), PigEBITS7 (n = 4), EbpA (n = 2), CAM5 (n = 1), WildBoar3 (n = 1), and a novel genotype XJMI-1 (n = 1). Phylogenetic analysis showed that all E. bieneusi genotypes belonged to group 1, which composed of over 300 genotypes and most of them have been identified in human and variety of animals, suggesting a risk of zoonotic transmission from farmed wildlife to humans., Graphical abstract Image 1, Highlights • Six genotypes were identified, including three zoonotic genotypes (D, EbpA ad PigEBIST7). • Farmed wildlife maybe a potential source of E. bieneusi infection for other animals and humans.

American mink (Neovison vison) is a significant source of global fur production. Except for a few studies from Denmark and Canada reporting antimicrobial resistance in bacteria isolated from clinic...

Severe acute respiratory syndrome coronavirus 2 has caused a pandemic in humans. Farmed mink (Neovison vison) are also susceptible. In Denmark, this virus has spread rapidly among farmed mink, resulting in some respiratory disease. Full-length virus genome sequencing revealed novel virus variants in mink. These variants subsequently appeared within the local human community.

American mink Neovison vison is a semi-aquatic mustelid that has been introduced throughout Europe. Several attempts to eradicate this invasive species have been carried out since its spread. In the Iberian Peninsula, an eradication program has started since 2001, as part of the national action plan for the conservation of European mink Mustela lutreola. Proper detection is crucial for management, both for monitoring variation in mink abundance and prevent the recolonization of cleared areas. Mink scats can be confounded with those of several same-sized mustelids, and with the spraints of Eurasian otter Lutra lutra, which also occur along watercourses. However, these difficulties can be overcome by non-invasive genetic methods. With the aim of providing a cost-effective and reliable technique for differentiating mink scats from those of the largest possible number of species with morphologically similar scats, we tested the effectiveness of an already available faecal mtDNA-based PCR–RFLP method for distinguishing mink- and otter faeces. We then applied the method for analysing scats collected and identified in the field by trained surveyors for monitoring the success of mink control operations. The PCR–RFLP method clearly differentiated mink scats from those of otters, as restriction enzymes produced well-defined different patterns. Eighty-five percent of 94 faecal samples could be assigned to a mustelid species. Only three out of seven putative mink samples were confirmed, suggesting that the accuracy of the visual identification of scats is questionable and genetic methods are needed for the reliable assessment of the success of eradication programs.

American mink Neovison vison is one of the most harmful non-indigenous species in Iceland and has been proven to be a useful indirect bioindicator and biomonitor for numerous environmental pollutants. Therefore, the main objective of the study was to determine the total nickel concentration in the spleen of 35 females and 30 males obtained from Brokey archipelago and the south coast of Hvammsfjörður (Dalabyggð, Iceland) using graphite furnace atomic absorption spectroscopy. We also assessed the correlation between nickel concentration and selected anatomical and morphological parameters, hypothesising that invasive alien N. vison is a promising candidate species for biomonitoring the deposition of this trace element. The results indicated a substantial variation in nickel concentration in the spleen tissue of examined animals. For males, the maximum concentration exceeded the average level by more than 16 times, and for females by more than 7 times. The correlation coefficient between morphometric features and the level of nickel concentration in the spleen did not show a significant relationship in any of the tested combinations, for all tested animals or for each sex separately. In conclusion, American mink in Iceland can be considered a promising species for qualitative and quantitative assessment of ecosystems in terms of nickel pollution.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of coronavirus disease and has been spreading worldwide since December 2019. The virus can infect different animal species under experimental conditions, and mink on fur farms in Europe and other areas are susceptible to SARS-CoV-2 infection. We investigated SARS-CoV-2 infection in 91 mink from a farm in northern Poland. Using reverse transcription PCR, antigen detection, and next-generation sequencing, we confirmed that 15 animals were positive for SARS-CoV-2. We verified this finding by sequencing full viral genomes and confirmed a virus variant that has sporadic mutations through the full genome sequence in the spike protein (G75V and C1247F). We were unable to find other SARS-CoV-2 sequences simultaneously containing these 2 mutations. Country-scale monitoring by veterinary inspection should be implemented to detect SARS-CoV-2 in other mink farms.

American mink (Neovison vison) is both a problematic invader and an economically valuable fur breed species in Belarus. The increasing scale of mink breeding for fur and the growing impact of this invasive species on the local ecosystems requires sound, novel strategies for managing both farm and wild populations. Containment of wild American mink populations under the effects of possible migration from the fur farms could be especially problematic. With that issue in mind, we have used microsatellite analysis todetermine the genetic polymorphism in two color breeds of farm-bred American mink in the populations of several Belorussian model fur farms, as well as the same characteristics for the feral populations on the territories adjacent to said fur farms. We confirm the presence of effective influx of mink into the wild from fur farms, determined through the means of analyzing microsatellite genotype data of feral and farm populations.

Pathogens are one of the factors driving wildlife population dynamics. The spread of pathogens in wildlife is currently highly related to the transmission of pathogens from farmed animals, which has increased with the constant development of farming. Here, we analysed the spatio‐temporal variation in the prevalence of Aleutian mink disease virus (AMDV) antibodies in feral American mink (Neovison vison) populations in Poland (1,153 individuals from nine sites) in relation to mink farming intensity. AMDV was detected in feral mink at all study sites and the prevalence ranged from 0.461 in the northern region to 0.826 in the western region. Mink males and adults were infected more often than females and subadults; the infection was also more frequent during the mink breeding season than during non‐breeding. The prevalence of AMDV changed non‐linearly in consecutive years and the peak of prevalence was every 3–4 years. The predicted AMDV prevalence was low at sites where the number of farmed mink was also low and increased linearly with the increase in the number of mink kept on farms. The predicted AMDV prevalence at sites with low mink farming intensity strongly varied between years, whereas at sites with high mink farming intensity, the predicted prevalence did not change significantly. AMDV infection affected the mink's body condition and caused an increase in the size of the spleen, liver and kidneys. This study shows that Aleutian mink disease strongly affects feral mink but the spatio‐temporal variation of its prevalence is complex and partly related to the transmission of the virus from farmed mink to feral populations. The study highlights the complexity of AMDV circulation in feral mink populations and implicates a potential spillover of the virus to native species.

The objective of this study was to determine the infection rate and genetic diversity of Cryptosporidium spp. in minks, foxes, and raccoon dogs, farmed in the Xinjiang Uygur Autonomous Region, Northwest China. Fresh fecal specimens were collected from individual cages of farmed minks (n = 214), blue foxes (n = 35), and raccoon dogs (n = 39) and examined using nested PCR based on the Cryptosporidium spp. small subunit rRNA gene. Cryptosporidium spp. was detected in 35 cages (12.2%, 35/288), with a higher infection rate detected in raccoon dogs (20.5%) compared with minks (12.1%) and blue foxes (2.9%). Sequence analysis showed that Cryptosporidium canis was the only species identified in blue foxes and raccoon dogs, while in the 26 Cryptosporidium-positive mink specimens, Cryptosporidium mink genotype (n = 17), C. canis (n = 7), and Cryptosporidium parvum (n = 2) were identified. Further analysis based on the 60-kDa glycoprotein (gp60) gene determined that both C. parvum isolates belonged to the subtype IIdA15G1, while eight of the 17 Cryptosporidium mink genotype isolates were a novel subtype that we have named XeA5G1. To the best of our knowledge, this is the first report of C. parvum subtype IIdA15G1 infection in minks. Since all the Cryptosporidium species/genotypes identified in minks, foxes, and raccoon dogs from Xinjiang have been previously found in humans, our results suggest that these fur animals may play a role in the transmission of zoonotic Cryptosporidium.

Coat colour is one of the most important qualitative traits of fur animals. Determining melanin pigments forming the basics of visible coat colour may contribute to a better understanding of the process of creating different coat colour variations in fur-bearing animals. This study aimed to (i) isolate pigment cells from the hair of American mink of 11 colour variations (standard brown, silverblue, palomino, black, wild type, sapphire, black cross, pearl, palomino cross, glow, and amber) using acid and alkali; and (ii) characterise the melanin pigments obtained. The purified pigment cells were observed under a light microscope and verified by spectrophotometry scanning and nuclear magnetic resonance spectroscopy. The method allowed for obtaining pure melanin specimens. Using acid and alkali to extract eumelanosomes did not affect their shape and structure; it also allowed for obtaining pheomelanin from the hair. The results have proven that the hair colour of the American mink is based on all types of melanin, and that its variations differ in terms of how much eumelanin and pheomelanin the hair contains.

Over 35 fur colours have been described in American mink (Neovison vison), only six of which have been previously linked to specific genes. Moyle fur colour belongs to a wide group of brownish colours that are highly similar to each other, which complicates selection and breeding procedures. We performed whole genome sequencing for two American minks with Moyle (m/m) and Violet (a/a m/m /p/p) phenotypes. We identified two frame-shift mutations in the gene encoding Ras-related protein-38 (RAB38), which regulates the trafficking of tyrosinase-containing vesicles to maturing melanosomes. The results highlight the role of RAB38 in the biogenesis of melanosomes and melanin and the genetic mechanism contributing to hair colour variety and intensity. These data are also useful for tracking economically valuable fur traits in mink breeding programmes.

From a longitudinal survey conducted on 30 Danish mink farms in 2016, 11.0% of faecal samples (456/4140) were positive for Cystoisospora laidlawi oocysts by microscopy, with 60% (189/315) of mink being positive at least once during the study period. Morphological analysis of sporulated oocysts identified Cystoisospora oocysts measuring 34.3 × 29.5 μm with an oocyst length/width (L/W) ratio of 1.2. The morphological features of the oocysts were identical to Isospora laidlawi previously morphological identified in farmed mink from Denmark and elsewhere. Phylogenetic analysis of 18S rDNA sequences (1221 bp) from three positive mink indicated that Cystoisospora from mink shared the highest genetic similarity to C. canis from a Canadian dog (99.6%). The phylogenetic analysis placed Cystoisospora from mink in a clade with other Cystoisospora isolates.

The release of domestic organisms to the wild threatens biodiversity because the introduction of domestic genes through interbreeding can negatively impact wild conspecifics via outbreeding depression. In North America, farmed American mink (Neovison vison) frequently escape captivity, yet the impact of these events on functional genetic diversity of wild mink populations is unclear. We characterized domestic and wild mink in Ontario at 17 trinucleotide microsatellites located in functional genes thought to be associated with traits affected by domestication. We found low functional genetic diversity in both mink types, as only four of 17 genes were variable, yet allele frequencies varied widely between captive and wild populations. To determine whether allele frequencies of wild populations were affected by geographic location, we performed redundancy analysis and spatial analysis of principal components on three polymorphic loci (AR, ATN1 and IGF‐1). We found evidence to suggest domestic release events are affecting the functional genetic diversity of wild mink, as sPCA showed clear distinctions between wild individuals near mink farms and those located in areas without mink farms. This is further substantiated through RDA, where spatial location was associated with genetic variation of AR, ATN1 and IGF1.

Commercial farming of endangered wildlife has potential to reduce poaching pressure on wild populations. However, poached products can be laundered as farmed products. A method for separating farmed from wild products is therefore essential for effective law enforcement. Meat (skeletal muscle) is a wildlife product whose origin cannot be correctly determined. This short communication reports an epigenetic approach to achieve the distinction using the methylation rate of the promoter of the α-actinin-3 (ACTN3) gene in gluteus maximus tissues of feral (n = 21) and farmed (n = 21) American mink, Neovison vison. Our results showed that the accuracy of assignment ranged from 59.5 to 76.2% on each of six CpG sites/site groups. Combination of the six CpG sites/site groups achieved 83.3% overall correct assignment, 90.5% for the farmed group and 76.2% for the wild group. These data suggest the methylation rate of promoters of selected genes could be an effective indicator to distinguish farmed meat from wild meat of wildlife species.

This paper examines the case for, and plausibility of, eradicating American mink Neovison vison from mainland Great Britain and its associated offshore islands. This invasive species causes extensive damage to native fauna throughout Europe, and the UK Government is obliged to eradicate it, if feasible, under the Bern Convention. Current mink control buys time, but is patchy and dependent on substantial funding in perpetuity. If enacted, eradication would be cheaper in the long term and much more effective in preserving native wildlife. The methodology of an eradication campaign is explored, together with risks, challenges, and a tentative timeline and cost. We judge that mink eradication is now logistically feasible, due to technological developments and experience gained from landscape‐scale control. Using live traps fitted with electronic sensors – ‘smart’ traps – as the primary means of catching mink would render the campaign efficient, humane and free of non‐target mortality and negative environmental impacts. The ecological benefits of mink eradication would be profound, including greatly improving prospects for water vole Arvicola amphibius populations. Reinvasion is highly unlikely. The greatest logistical challenge is probably removing mink from Scottish west coast islands. Eradication might take around a decade and be dependent on co‐ordination between many conservation, fishing, farming, and water‐related organisations, together with the consent of landowners. By adding alarms to existing mink traps, land and water managers can pave the way to eradication now. A mink‐free Great Britain would plausibly cost tens of millions of pounds, against which could be set the limitless future costs of mink control. Such a campaign would be by far the world's largest invasive predator eradication project by geographical area and would set a precedent for citizen‐led conservation action globally. Regional trials would be extremely valuable in determining the costs and practicality of a GB‐wide campaign.

Detection probability is an important input when studying and managing species. It reduces the miscalculations of the estimates of occupancy, population abundances and their trends inherent to the imperfect detection during sampling. However, detection probability may vary in relation to environmental and biological factors, such as the presence of other species of similar ecological niche. We used a two-species single-season occupancy model to analyse the detection probability of the native Eurasian otter Lutra lutra and the invasive American mink Neovison vison in the northeast of the Iberian Peninsula and to test for potential differences in their detection when co-occurring and when not. Despite the known behavioural change of American mink towards a more terrestrial diet and a more diurnal activity pattern in the presence of Eurasian otter, their detectability did not vary when both species co-occurred versus when they did not. However, we observed seasonal differences in the probability of detection. Specifically, the probability of detection was higher in winter for both species. Furthermore, Eurasian otter was more often detected in sites with clay substrate, whereas American mink in sites with clay and rocks. These results indicate that the effectiveness of monitoring of Eurasian otter and American mink remains independent of the species co-occurrence. Yet, seasonal variations in the detection should be taken into account when monitoring.

Invasive non-native species can become reservoirs of zoonotic pathogens and cause their spread during colonization, increasing the risk of zoonoses transmission to both wild hosts and humans. American mink (Neovison vison) are considered an important invasive mammal species responsible for carrying endoparasites. The aim of our study was to evaluate the role of feral American mink as a possible transmission vector of Echinococcus spp. and Toxocara spp. in wildlife. We analysed the frequency of American mink exposure to both parasites, the spatial distribution in Poland, and the variability over time on the basis of specific antibody presence using ELISA and Western blot. Alimentary tract analyses revealed that American mink do not serve as definitive hosts for these parasites. Altogether, 1100 American mink were examined. The average seropositivity for American mink was 14.2% for echinococcosis and 21.7% for toxocarosis; dual-seropositivity was detected in only 6.0%. Seroprevalence of both parasites differed between study sites and significantly increased over time in Toxocara spp. Thus, our study revealed that free-living American mink are exposed to parasites and likely to be involved in the maintenance of both Echinococcus spp. and Toxocara spp. in the wild as paratenic hosts.

European and American minks (Mustela lutreola and Neovison vison, respectively) are very similar in their ecology, behavior, and morphology. However, the American mink is a generalist predator and seems to adapt better to anthropized environments, allowing it to outcompete the European mink in areas where it has been introduced, threatening the survival of the native species. To assess whether morphological differences may be contributing to the success of the American mink relative to the European mink, we analyzed shape variation in the cranium of both species using 3D geometric morphometrics. A set of 38 landmarks and 107 semilandmarks was used to study shape variation between and within species, and to assess how differences in size factored into that variation. Sexual dimorphism in both size and shape was also studied. Significant differences between species were found in cranial shape, but not in size. Relative to American mink, European mink have a shorter facial region with a rounder forehead and wider orbits, a longer neurocranium with less developed crests and processes, and an antero‐medially placed tympanic bullae with an anteriorly expanded cranial border. Within species, size‐related sexual dimorphism is highly significant, but sexual dimorphism in shape is only significant in American mink, not in European mink. Additionally, two trends common to both species were discovered, one related to allometric changes and another to sexual size dimorphism. Shape changes related to increasing size can be subdivided into two, probably related, groups: increased muscle force and growth. The first group somewhat parallels the differences between both mink species, while the second group of traits includes an anterodorsal expansion of the face, and the neurocranium shifting from a globous shape in small individuals to a dorsoventrally flattened ellipse in the largest ones. Finally, the sexual dimorphism trend, while also accounting for differences in muscle force, seems to be related to the observed dietary differences between males and females. Overall, differences between species and sexes, and shape changes with increasing size, seem to mainly relate to differences in masticatory‐muscle volume and therefore muscle force and bite force, which, in turn, relate to a wider range of potential prey (bigger prey, tougher shells). Thus, muscle force (and dietary range) would be larger in American mink than in European mink, in males than in females, and in larger individuals than in smaller ones., Cranial shape and size variation in European (Mlu) and American minks (Nvi) were studied. Both species differed in shape but not size, while sexes within each differed in size but in shape only for Nvi. Allometric shape changes were related to growth and sexual dimorphism. Overall, differences among species, sexes, and sizes related to masticatory‐muscle volume, which suggests that muscle force (and dietary range) would be larger in Nvi than in Mlu, in males than in females, and in larger mink.

The European mink (Mustela lutreola) is listed as a critically endangered species because of ongoing population reduction from habitat degradation and the effects of introduced species, such as American mink (Neovison vison). This small, fragmented population becomes vulnerable to many other threats, including diseases. Leishmaniosis is a zoonotic disease caused by the protozoan parasite Leishmania infantum found in the Mediterranean area, which affects many mammals, including wild small mammals. Furthermore, clinical disease caused by L. infantum has recently been described in other mustelids. To assess the exposure to Leishmania sp. infection in mink species in northern Spain, blood samples from 139 feral American mink and 42 native European mink from north Spain were evaluated for Leishmania sp. infection using enzyme-linked immunosorbent assays against Leishmania spp. antibodies, with 52.4% of American mink and 45.3% of European mink being found seropositive. This finding raises questions regarding how the disease may affect these species and the potential repercussions for conservation efforts. Despite a high seroprevalence being observed in wild mink of both species in this study, association with clinical or pathologic signs of disease has yet to be elucidated.

Development of genome-enabled selection and providing new insights in the genetic architecture of economically important traits are essential parts of mink breeding programs. Availability of a contagious genome assembly would guarantee the fundamental genomic studies in American mink (Neovison vison). Advances in long-read sequencing technologies have provided the opportunity to obtain high quality and free-gaps assemblies for different species. The objective of this study was to generate an accurate genome assembly using Single Molecule High-Fidelity (HiFi) Sequencing for American mink. The whole genome sequences of 100 mink were analyzed to select the most homozygous individual. A black American mink from Millbank Fur Farm (Rockwood, ON, Canada) was selected for PacBio sequencing. The total number of 2,884,047 HiFi reads with the average size of 20 kb were generated using three libraries of PacBio Sequel II System. Three de novo assemblers including wtdbg, Flye and IPA were used to obtain the initial draft of assembly using the long reads. The draft generated using Flye was selected as the final assembly based on the metrics of contiguity and completeness. The final assembly included 3,529 contigs with the N50 of 18.26 Mb and the largest contig of 62.16 Mb. The length of genome assembly was 2.66 Gb with 85 gaps. These results confirmed that high-coverage and accurate long-reads significantly improved the American mink genome assembly and successfully generated more contagious assembly. The chromosome conformation capture data will be integrated to the current draft to obtain a chromosome-level genome assembly for American mink at the next step of the project.

Invasive alien species are a well-known and pervasive threat to global biodiversity and human well-being. Despite substantial impacts of invasive alien species, quantitative syntheses of monetary costs incurred from invasions in national economies are often missing. As a consequence, adequate resource allocation for management responses to invasions has been inhibited, because cost-benefit analysis of management actions cannot be derived. To determine the economic cost of invasions in Germany, a Central European country with the 4th largest GDP in the world, we analysed published data collected from the first global assessment of economic costs of invasive alien species. Overall, economic costs were estimated at US$ 9.8 billion between 1960 and 2020, including US$ 8.9 billion in potential costs. The potential costs were mostly linked to extrapolated costs of the American bullfrog Lithobates catesbeianus, the black cherry Prunus serotina and two mammals: the muskrat Ondatra zibethicus and the American mink Neovison vison. Observed costs were driven by a broad range of taxa and mostly associated with control-related spending and resource damages or losses. We identified a considerable increase in costs relative to previous estimates and through time. Importantly, of the 2,249 alien and 181 invasive species reported in Germany, only 28 species had recorded economic costs. Therefore, total quantifications of invasive species costs here should be seen as very conservative. Our findings highlight a distinct lack of information in the openly-accessible literature and governmental sources on invasion costs at the national level, masking the highly-probable existence of much greater costs of invasions in Germany. In addition, given that invasion rates are increasing, economic costs are expected to further increase. The evaluation and reporting of economic costs need to be improved in order to deliver a basis for effective mitigation and management of invasions on national and international economies. Wirtschaftliche Kosten invasiver Arten in Deutschland. Invasive gebietsfremde Arten sind eine bekannte und weit verbreitete Bedrohung für die globale Artenvielfalt und das Wohlergehen des Menschen. Trotz erheblicher Auswirkungen invasiver gebietsfremder Arten fehlen häufig quantitative Synthesen der finanziellen Kosten, die durch Invasionen entstehen. Infolgedessen wurde eine angemessene Ressourcenzuweisung für Managementreaktionen auf Invasionen verhindert, da keine Kosten-Nutzen-Analyse von Managementmaßnahmen abgeleitet werden kann. Um die wirtschaftlichen Kosten von Invasionen in Deutschland, einem mitteleuropäischen Land mit dem viertgrößten BIP der Welt, zu ermitteln, haben wir veröffentlichte Daten analysiert, die aus der ersten globalen Bewertung der wirtschaftlichen Kosten invasiver gebietsfremder Arten stammen. Insgesamt wurden die wirtschaftlichen Kosten zwischen 1960 und 2020 auf 9.8 Milliarden US-Dollar geschätzt, einschließlich potenzieller Kosten in Höhe von 8.9 Milliarden US-Dollar. Die potenziellen Kosten waren hauptsächlich auf die extrapolierten Kosten des amerikanischen Ochsenfrosches Lithobates catesbeianus, der Tollkirsche Prunus serotina und zweier Säugetiere zurückzuführen: des Bisamratten Ondatra zibethicus und des amerikanischen Nerz Neovison vison. Die beobachteten Kosten wurden von einer breiten Palette von Taxa getrieben und waren hauptsächlich mit kontrollbezogenen Ausgaben und Ressourcenschäden oder -verlusten verbunden. Wir haben einen erheblichen Anstieg der Kosten im Vergleich zu früheren Schätzungen und im Laufe der Zeit festgestellt. Wichtig ist, dass von den in Deutschland gemeldeten 2.249 gebietsfremden und 181 invasiven Arten nur 28 Arten wirtschaftliche Kosten verzeichneten. Daher sollte die Gesamtquantifizierung der Kosten invasiver Arten hier als sehr konservativ angesehen werden. Unsere Ergebnisse zeigen einen deutlichen Mangel an Informationen in der öffentlich zugänglichen Literatur und in staatlichen Quellen zu Invasionskosten auf nationaler Ebene, was die höchstwahrscheinliche Existenz viel höherer Invasionskosten in Deutschland maskiert. Angesichts der steigenden Invasionsraten werden die wirtschaftlichen Kosten voraussichtlich weiter steigen. Die Bewertung und Berichterstattung der wirtschaftlichen Kosten muss verbessert werden, um eine Grundlage für eine wirksame Eindämmung und Bewältigung der Invasionen in die nationale und internationale Wirtschaft zu schaffen. Costos económicos de las especies invasoras en Alemania. Las especies invasoras representan una conocida amenaza en general para la biodiversidad del planeta y el bienestar humano. A menudo se omite la cuantificación de los costes económicos que provocan las especies invasoras, a pesar de los impactos sustanciales que ellas provocan. En consecuencia, el reparto de los recursos para el manejo de las respuestas es inadecuado ante las invasiones, por lo tanto no es posible obtener un análisis de los costos y beneficios de las acciones de manejo. Para determinar los costos económicos de las invasiones en Alemania, un país Centroeuropeo con el 4to producto interno bruto más grande del planeta, se analizaron datos publicados en la primera evaluación global de los costes económicos de especies invasoras. En general se estimaron costes económicos de US $9.8 mil millones entre los años 1960 y 2020, incluyendo US $8.9 mil millones en costos potenciales. Los costos potenciales se asociaron con los costes extrapolados de la rana toro americana Lithobates catesbeianus, el cerezo negro Prunus serotina y dos mamíferos: la rata almizclera Ondatra zibethicus y el visón americano Neovison vison. Los costes observados se condujeron entre una amplia variedad de taxa de los cuales la mayoría se asociaron con gastos relacionados con el control de las especies y daños a los recursos o pérdidas relacionadas con invasiones. Se identificó un incremento considerable de los costes relacionados con estimaciones previas y a través del tiempo. De manera importante, de las 2,249 especies exóticas y 181 especies invasoras, solo se han reportado costes de 28 especies invasoras en Alemania. Por lo tanto, el total de los costes cuantificados de las especies invasoras que se presentan aquí deben de mostrarse como muy moderados. Se destaca una ausencia de información entre la literatura de acceso libre y las fuentes gubernamentales sobre los costes de las invasiones s a nivel nacional, enmascarando así la alta probabilidad de que existan mayores costes por invasiones en Alemania. Adicionalmente, dado que la tasa de invasión se encuentra en incremento, se espera que los costes económicos sufran un incremento. Se requiere mejorar la evaluación y el reporte de los costes económicos para sentar un adecuado precedente para la mitigación y manejo efectivo de las invasiones en la economía nacional e internacional. Ekonomické náklady na invazivní druhy v Německu. Nepůvodní invazní druhy jsou dobře známou a všudypřítomnou hrozbou pro celosvětovou biodiversitu i blahobyt člověka. Navzdory podstatným dopadům biologických invazí však často postrádáme přehled o jejich nákladovosti pro národní ekonomiky. V důsledku toho byla omezena i adekvátní alokace zdrojů pro management biologických invazí, jelikož nebylo možné vypracovat analýzu nákladů a přínosů takových akcí. Cílem této studie bylo pomocí speciálně vytvořené databáze zhodnotit náklady způsobené invazními druhy v Německu, které je čtvrtou zemí s nejvyšším HDP na světě. Celkově byly ekonomické náklady invazních druhů mezi lety 1960 a 2020 odhadnuty na 9.8 miliardy amerických dolarů. Jednalo se především o potenciální odhadnuté náklady způsobené severoamerickým skokanem volským Lithobates catesbeianus, střemchou pozdní Prunus serotina a dvěma savci – ondatrou pižmovou Ondatra zibethicus a norkem americký Neovison vison. Pozorované náklady byla způsobené různými skupinami organismů a většinou byly spojeny s kontrolou jejich šíření a jimi způsobenými škodami. V průběhu času bylo oproti dřívějším odhadům zaznamenáno značné zvýšení těchto ekonomických škod. V Německu žije 2249 nepůvodních organismů, z nichž je 181 považováno za invazní, avšak pouze u 28 existují ekonomicky vyčíslené škody. Reálná výše těchto škod je tedy očekávatelně podstatně vyšší. Tato zjištění poukazují na značný nedostatek takových údajů v dosažitelných informačních zdrojích, jenž velmi pravděpodobně maskuje existenci podstatně vyšších škod způsobených invazními druhy v Německu. Jelikož počet invazních druhů v zemi roste, lze do budoucna očekávat i růst jimi způsobených škod. Je tedy potřeba zlepšit hodnocení a vykazování ekonomických nákladů souvisejících s invazními druhy, aby bylo možné vytvořit podmínky pro jejich eliminaci a management na národní i mezinárodní úrovni. Coûts économiques des espèces envahissantes en Allemagne. Les espèces exotiques envahissantes sont une menace bien connue et omniprésente pour la biodiversité mondiale et le bien-être humain. Malgré les connaissances sur les impacts substantiels de ces espèces, les synthèses quantitatives des coûts monétaires induits par les invasions sur les économies nationales font souvent défaut. De fait, le rapport coûts-avantages des mesures de gestion des invasions biologiques est souvent difficile à obtenir. Cela a nécessairement des conséquences négatives sur l’allocation adéquate de ressources dédiées à ces mesures et actions destinées à prévenir ou contrôler les espèces exotiques envahissantes. Pour déterminer le coût économique des invasions en Allemagne (pays européen avec le quatrième PIB le plus important au monde), nous avons analysé les données publiées collectées à partir de la première compilation mondiale des coûts économiques des espèces exotiques envahissantes. Dans l'ensemble, les coûts économiques ont été estimés à 9,8 milliards de dollars entre 1960 et 2020, dont 8,9 milliards de dollars de coûts potentiels. Les coûts potentiels étaient principalement liés aux coûts extrapolés du ouaouaron d'Amérique Lithobates catesbeianus, du cerisier noir Prunus serotina et de deux mammifères: le rat musqué Ondatra zibethicus et le vison d'Amérique Neovison vison. Les coûts observés étaient attribuables à un large éventail de taxons et principalement associés aux dépenses liées au contrôle et aux dommages ou pertes affectant les ressources humaines. Nous avons identifié une augmentation considérable des coûts au cours du temps, avec des coûts supérieurs aux estimations réalisées précédemment. Il est important de noter que sur les 2249 espèces exotiques et 181 espèces envahissantes signalées en Allemagne, seules 28 espèces ont des coûts économiques reportés dans la base de données considérée. Par conséquent, les coûts quantifiés ici doivent être interprétés avec prudence. Nos résultats mettent donc en évidence un manque flagrant d'informations dans la littérature librement accessible et les sources gouvernementales sur les coûts des invasions au niveau national, masquant l'existence hautement probable de coûts beaucoup plus élevés en Allemagne. De plus, il ne fait aucun doute que l’augmentation toujours croissante des phénomènes d'invasion biologique sera liée à l’augmentation concomitante des coûts économiques associés. L'évaluation et la communication des coûts économiques doivent nécessairement être améliorées pour contribuer à l’établissement et l’implémentation de mesures de gestion efficaces des invasions aux échelles nationale et internationale.

Leishmania infantum produces an endemic disease in the Mediterranean Basin that affects humans and domestic and wild mammals, which can act as reservoir or minor host. In this study, we analyzed the presence of the parasite in wild American minks, an invasive species in Spain. We screened for L. infantum DNA by PCR using five primer pairs: Two targeting kinetoplast DNA (kDNA), and the rest targeting the ITS1 region, the small subunit of ribosomal RNA (SSU) and a repetitive sequence (Repeat region). The detection limit was determined for each method using a strain of L. infantum and a bone marrow sample from an infected dog. PCR approaches employing the Repeat region and kDNA (RV1/RV2 primers) showed higher sensitivity than the other PCR methods when control samples were employed. However, only PCR of the Repeat region and nested PCR of SSU (LnSSU) detected the parasite in the samples, while the other three were unable to do so. The majority of the analyzed animals (90.1%) tested positive. American mink may act as an incidental host of the disease for other mammals and should be further investigated, not only for their negative impact on the local fauna, but also as carriers of zoonotic diseases.

The American mink, Neovison vison, is an invasive species in Chile. Its impact on native fauna and public health has not been studied in depth in the country. In this study, we searched for gastrointestinal parasites, including helminths and zoonotic Cryptosporidium sp., the presence of Trichinella sp. in muscle, and the renal carriage of pathogenic Leptospira sp. in minks caught on Navarino Island, "Magallanes y la Antartica Chilena" Region, and Maullin and Ancud, "Los Lagos" Region, Chile. A total of 58, 15, and 21 minks from Navarino Island, Maullin, and Ancud, respectively, were examined for Trichinella sp. (artificial digestion of muscle). A total of 36, 11, and 17 minks from Navarino Island, Maullin, and Ancud, respectively, were examined for pathogenic Leptospira species (molecular detection of LipL32 gen fragment in renal tissue) infection. Finally, 45, 11, and 17 minks from Navarino Island, Maullin, and Ancud, respectively, were analyzed to detect gastrointestinal parasites (by optical inspection of the digestive tract for helminths, and by both Ziehl-Neelsen stain and molecular detection of small subunit-ribosomal DNA for Cryptosporidium species). Trichinella larvae were not observed. Pathogenic Leptospira sp. was detected in 22 samples: 15 from Navarino Island, 3 from Maullin, and 4 from Ancud. Two nematodes, belonging to Ascaridinae (subfamily) and Pterygodermatites (Paucipectines) sp., were found in samples of two minks from Navarino Island. Oocysts and DNA of Cryptosporidium sp. were detected in three fecal samples from Navarino Island. Further studies could determine the zoonotic potential of Cryptosporidium sp., as well as the potential impact of the zoonotic Leptospira sp. on the human population of the Navarino Island, Maullin, and Ancud districts. The enemy release theory could explain the low helminth species richness in the minks. In addition, we did not find evidence of parasite transmission from native fauna.

Reintroduction is an important strategy to restore or re-establish wild populations of endangered species. Pre-release training is a necessary step to ensure post-reintroduction survival. However, studies reported contradicting outcomes after pre-release training of juveniles and adults. This study used farmed and feral American mink (Neovison vison) to analyze the influence of captive breeding on the morphology, structure and efficiency of the two major hindlimb levers, the femur and tibia pivoted by hip and knee joints that are essential for locomotion. Results showed that captive breeding did not alter the sexual dimorphism of the two levers that are related to survival in the wild. Captive-bred mink showed slightly altered morphology of the femur and fundamental structure of the hindlimb levers that improved efficiency, but this resulted in reduction of performance related to foraging in both terrestrial and aquatic environments, especially for females. These findings suggest that reintroduction of mustelid as exampled by the mink here should focus on juveniles because the skeletal alterations associated with captive rearing were recorded only among adults and are irreversible in adulthood. In contrast, captive-reared juveniles showed no skeletal alterations and would be expected to recovery from any atrophy of the muscular system caused by captive rearing for shorter durations. Our results support the application of pre-release training of juveniles in enriched environments as a method for alleviating structural alteration of appendages and enhancing locomotion to increase survival probability in complex habitats.

Genetic testing using STR sequences is a fundamental element of investigative and judicial activities in various types of cases involving animals, such as theft of animals or products derived from ...

Based on the materials of 23 fur-bearing animal farms of the Russia for different periods of years, a comparative assessment of the reproductive capacity of sable and mink females of standard breeds (wild type) has been carried out. It was established that during intrabreeding differentiation according to the overall color of the hair coat (almost black, black-brown, dark brown and chestnut), the lowest reproduction level is characterized by darker females of sable, which are a significant increase in the number of them, mated with male, but not given offspring (barren females). According to the results of interbreed comparisons of sables and minks, parallelism was found in the variability of the reproductive capacity of females, which is manifested in the fact that, in contrast to relatively light animals, animals that are dark in color are characterized by a greater number of barren females and low fecundity.

Pre-weaning diarrhea in mink kits (PWD), also known as “sticky kits” is a multifactorial syndrome of considerable concern in the mink production. Evidence based treatment protocols are not available, and treatment is therefore empirical and often based on the use of antimicrobials. The purpose of the study was to test the effect of 3 alternative treatments to a standard antibiotic treatment, to characterize the study groups microbiologically, and finally to compare the intestinal microbiota of the different treatment groups at the age of 42 days. In total, 226 one to three week old mink kits with PWD from 36 litters were treated with either 1) Lactobacillus reuteri, 2) benzylpenicillin, 3) Ringer lactate or 4) amoxicillin (controls). Effects of the treatments were measured as weight gain from day 0 to day 15 and mortality. Multivariable linear mixed model regression showed no significant difference in weight gain between probiotic-, penicillin or fluid-treated mink kits and the amoxicillin treated controls. There was also no significant difference in mortality risk between the treatment groups. Bacterial culture and next generation sequencing of the viral contents showed that the study groups were uniform with a high frequency of Staphylococcus intermedius group (SIG) bacteria, Escherichia coli, Enterococcus hirae, Mamastrovirus and Sapovirus which were representative for mink kits with PWD. 16S sequencing results of the bacterial microbiota, when the kits were 42 days old were dominated by clostridia in all groups and showed no clear differences in the bacterial composition between the different treatment groups.

In this study we investigated the robustness of the WelFur welfare assessment system for farmed mink (Neovison vison) to date of assessment in the winter and growth assessment periods. The prevalence of occurrences of certain measurements was hypothesised to increase with date of assessment (too thin, fur-chewing and stereotypic behaviour in the winter period and injuries, diarrhoea and exploratory mink in the growth period). The welfare was assessed on eight Danish mink farms according to the WelFur-Mink protocol. Each farm was assessed once in the nursing period (to be able to calculate WelFur-Mink scores), four times in the growth period and three times in the winter period. WelFur scores were calculated based on the assessments in the three periods: one calculation for each assessment in the winter and growth periods. The odds of fur-chewing increased with date of assessment in the winter period, and the odds of injuries, diarrhoea and exploratory mink increased with date of assessment in the growth period. The odds of too thin mink in the winter period decreased, ie the change was in the opposite direction to what was expected. The effect of these changes on the aggregated WelFur scores on the higher levels was limited, but could potentially lead to changes in the overall welfare categorisation of farms if the principle scores were close to a threshold between two categories. A potential way to eliminate the effect of date of assessment could be to develop a correction factor for the measurements that can be expected to change within each assessment period.

The American mink Neovison vison has been introduced to Italy for fur farms in the 1950s. Since the 1970s, free-ranging individuals are present in north-eastern Italy, where an expanding population still occurs. In our work, we aimed at assessing the seasonal diet of invasive American mink introduced to north-eastern Italy. Thus, a total of 195 mink scats (N = 73, June 2007; N = 57, September 2007; N = 65, February 2008) were collected. Scats were washed and food remains isolated and classified through comparison with reference collections and atlases. Absolute and relative frequencies, as well as the estimated volume of each prey category were computed. The endemic Italian water vole Arvicola italicus represented the staple of the diet of the American mink in June (relative frequency: 20.4%, total volume in diet: 38.1%) and September (relative frequency: 22.7%, total volume in diet: 52.0%). Other small mammals, amphibians (Rana spp. and Pelophylax spp.) and the invasive red swamp crayfish Procambarus clarkii were mostly consumed in cold months, when water voles are not available. Differently from other study areas, wading birds and fish were rarely consumed, possibly because of their low local availability, if compared with small mammals. No law currently protects the endemic water vole, which may be furtherly threatened by the potential range expansion of invasive minks. Therefore, eradication of this alien carnivore should be recommended before local population decline of water vole become irreversible, and before minks reach populations of native riverine mustelids, i.e. the western polecat and the Eurasian otter.

Introduction: Farm mink (Neovison vison) can be naturally exposed to T. canis and T. leonina pathogens on the farm. If mink were hosts, it would imply some veterinary public health as well as animal welfare issues. For this reason, the aim of the study was to determine whether mink might be definitive or paratenic hosts of these parasites. Material and Methods: Four groups of mink were infected with both parasite species using larvated eggs or feed containing mouse tissue previously infected with the parasites. Following inoculation, the infections were monitored in vivo by faecal examination for 14 weeks p.i., and then western blotting and ELISA were performed. Results: Coprology did not reveal any canine roundworm eggs, neither were nematodes found in mink intestines during post mortem examination. The specific IgG antibodies recognising excretory/secretory (ES) antigens of both parasite species were identified in mink sera. Single T. leonina tissue larvae were found in digested organs. Conclusions: Our results confirm that farm mink may contribute both T. canis and T. leonina infections. It was proved that farm mink were not their definitive hosts, and therefore mink faeces need not be considered a source of canine roundworm eggs in any soil it fertilises. Nonetheless, as farm mink may be a paratenic host for both parasite species, this may have some impact on the health and welfare of infected animals.

Introduction: Canine roundworm T. canis and T. leonina infections were investigated in experimentally infected farm mink (Neovison vison) to describe the pattern of pathological lesions in this paratenic host. Material and Methods: Infections in mink developed following ingestion of embryonated eggs of either parasite or mice tissue infected with both parasite species. Results: Comparative analysis of haematoxylin- and eosin-stained slides showed essential differences among the experimental groups. The lesions observed included eosinophil and mononuclear inflammatory infiltrates of the intestinal wall and local lymph nodes, inflammation and haemorrhages in liver tissues, and interstitial inflammation and mineralisation of the kidneys and lungs. Larvae migrating through the minks’ bodies also caused particularly salient enlargement of lymphoid follicles in the spleen and inflammatory infiltrates of mononuclear cells in skeletal and heart muscles. Conclusions: It is assumed that histopathological lesions appeared as a local and general host response to invasive L3 T. canis and T. leonina larvae migrating through the tissues of infected farm mink. Interestingly, mink infected with embryonated eggs had more pronounced lesions than animals infected with tissue larvae. Detailed histopathological examinations of parenchymal organs and striated muscles revealed lesions resembling those observed in other paratenic host species due to toxocarosis.

Helminthological autopsies of Mustelids from various districts of Pskov, Тver and Smolensk region were carried out. To determine the prevalence rates of the infestation, an extensive invasion index was used. According to the results of helminthological autopsies, a list of detected helminthes is given. For the first time on the study area, 14 species of helminthes were recorded in studied Mustelids. Two of the found species of helminthes parasitize in Mustelids in larval form. The maximum variety of species is observed among the Nematoda class. The data on the number of detected helminth species in Mustelids in certain districts of the Tver, Pskov and Smolensk regions, as well as indicators of the frequency of helminthes were given. The maximum number of helminth species is recorded in Mustelids in the Novosokolnichesky district of the Pskov region. Extensiveness of invasion of all studied species of Mustelids, excluding otter, is 100%. According to the indicators of extensiveness of invasion in the studied Mustelids, Isthmiophora melis, Capillaria mucronata, Capillaria putorii, Filaroides martis are prevalent. The maximum number of species of parasitic worms is recorded in pine marten. The research results indicate the dominant influence of the trophic factor in the formation of the helminth fauna of martens that inhabit the study areas.

The southernmost archipelago of the Americas is dominated by invasive mammals that outnumber their native counterparts. Despite the relatively low ability of most invasive mammals to cross cold sea water channels, invaders are apparently colonizing new islands. Our objective was to provide an assessment of the expansion of invasive mammals within these sub-Antarctic ecosystems, determine whether human-mediated movement of invasive species is a plausible dispersal mechanism, and identify areas likely to be colonized in the near future. We report a decade of fieldwork (2006–2017) in 44 sites on 13 islands within the Cape Horn Biosphere Reserve including opportunistic and systematic camera trapping, carnivore diet, questionnaires, small mammal trapping, and walks/transects. We found new records of invasive mammals on seven islands, particularly for American mink (Neovison vison) and American beaver (Castor canadensis). Interviews with fishermen showed that mink, dogs (Canis familiaris), and small rodents are likely passengers in vessels. Finally, species distribution models revealed that the putative invasive-free Cape Horn National Park (55°S) is suitable for several invasive species, suggesting a high risk of invasion if species are introduced. We conclude that it is urgent to implement barriers to dispersal to prevent further invasion. In the case of dogs and cats (Felis catus), the first step should be control actions that target pet owners. Finally, we highlight the need of systematic, long-term biodiversity monitoring and citizen science in the Cape Horn Archipelago and common conservation guidelines for the terrestrial sub-Antarctic ecosystems.

The aim of this review was to define the most important factors that affect the reproductive success of farmed mink. The biology of mink reproduction is unique when comparing it with other farmed fur animals. The article emphasizes the importance of optimal environmental conditions in prevention of reproductive disorders. The novel attempts to the mating schedule, optimal diet and body condition of dams, kits transfer between dams, these are only examples of advantageous procedures used in mink farming to increase the effectiveness of reproduction.

This paper reports the results of stationary studies on the ecology of the American mink (Neovison vison Schreb.) on three small rivers of the Sikhote-Alin region from 2003 to 2018. The population density in the field stations range from 0.4 to 2.2 individuals per 1 km of watercourse. Cyclic changes in the density of the mink population were found to occur with a period of about six years (rS = 0.68, P = 0.01). Hunting of low intensity did not affect the number and growth of the mink population. The correlation between floods and annual precipitation and dynamics of density was weak and unreliable. In the predator’s diet, three main forage groups (mammals, frogs, and fish) were singled out, the ratio of which varied in the basins of different rivers and according to the seasons of the year.

Study into the effect of vitamins A and E on total and differential leukocyte count, as well as morphometric parameters of lymphocytes in three carnivorous species—dark brown American mink (Neovison vison, Mustelidae), blue fox (Vulpes lagopus, Canidae), and silver fox (V. vulpes, Canidae)—was conducted. The highest white blood cells count (WBC count) and the largest surface area of lymphocytes and their nuclei in the peripheral blood were observed in mink, while the lowest indices were found in silver fox. Additional supplementation with vitamins A and E for 14 days had no effect on the WBC and differential leukocyte count, except for silver foxes receiving vitamin E, in which a decrease in relative eosinophils and monocytes content was observed. The action of vitamins was mainly manifested in changes in the lymphocytes’ morphometric parameters. The addition of vitamin A into the diet of mink and silver fox and vitamin E into only mink’s diet led to an increase in the surface area of lymphocytes and, in some cases, their nuclei, which was accompanied by a rise in the cytoplasm size in mink cells. In blue fox, on the contrary, both vitamins induced a decrease in the surface area of the lymphocytes and their nuclei. The observed changes may be associated with the immunomodulatory effects of vitamins A and E of the studied species of carnivorous mammals, while the found differences may be associated with features of the morphologic and functional organization of lymphocytes and the immune status.