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1.
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2.
Despite efforts undertaken to conserve the endangered European mink, its reproduction is still poorly studied. The aim was to study its reproductive cyclicity, faecal progesterone concentration and ovarian changes during early pregnancy, with the emphasis on the pre-implantation period and implantation. During the 2004 breeding season, oestrous cycle was monitored in 39 females as well as ovarian changes during early pregnancy in 22 females. During the 2007 breeding season, faecal progesterone concentration measured by radioimmunoassay was monitored during pregnancy in 10 females throughout their pregnancy. The breeding season 2004 started on March 18 and ended on May 10, with the peak recorded in April. The duration of first oestrus was 1–12 days. If not mated, the vast majority of females entered second oestrus after 12–55 days. In general, relatively low faecal progesterone values were detected in European mink; an average of 42.69 ± 4.70 ng/g faeces in oestrous females with a maximum of 176.44 ± 23.01 ng/g faeces on pregnancy day 12. anova indicated a significant effect of the pregnancy stage. Post hoc comparisons with Fisher least significant difference (LSD) test revealed that faecal progesterone concentrations on days 8 and 12 post coitum (p.c.), but not at the end of pregnancy (day 40), were higher when compared with the initial oestrous level. Implantation in this species occurs on day 12 p.c. and was indicated by prominent uterine swellings and failure to flush the uterine horns beyond this day. Advanced luteogenesis was observed with prominent corpora lutea found in ovaries around the time of implantation. To conclude, European mink is a seasonally polyoestrous species; the early pregnancy of European mink resembles that of European polecat, i.e. in both species, implantation occurs on day 12 p.c. without any implantation delay.  相似文献   

3.
A survey was carried out to investigate the presence of cranial helminths in 337 American minks (Mustela vison) from Spain. This information was obtained partly in order to evaluate potential conservation problems and sanitary risks to the congeneric European mink (Mustela lutreola), one of the most endangered carnivores in the world. Skulls and rectal faeces of each specimen were simultaneously analysed. Troglotrema acutum and Skrjabingylus nasicola were found in 5.6% of the M. vison analysed. No cranial lesions were seen in any of the examined skulls. The finding of both helminths in Spanish free-living M. vison specimens enlarges their natural definitive host spectrum in Western Europe. One relatively important focus of T. acutum in M. vison was detected (30.4%) in the Spanish Alava province while S. nasicola was found to be very infrequent. The suitability of both analytical methods was assessed in order to know to what degree coprological analysis reflects the real prevalence of cranial helminths in this host. It is possible to conclude that coprological analysis can be used instead of necropsies to analyse the possible incidence of pathogenic cranial helminths in mustelids. This aspect is very important and useful when trying to analyse the helminthological status of endangered species such as the native mink (M. lutreola) particularly in areas where both congeneric species are present and strict competition occurs.  相似文献   

4.
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5.
The distribution of diagnoses of mortality in mink submitted to the Danish Veterinary Laboratory (DVL) for diagnostic investigation in the calendar year 1997 was compared with the diagnoses of mortality in all dead mink collected at 4 selected farms (project farms) during the same period. A total of 1,015 submitted mink and 1,149 mink from the 4 project farms were subjected to post mortem investigation. The average size (breeding stock) of the project farms was larger than Danish farms on average. However, the distribution of colour types of the mink was comparable. The seasonal distribution of the material from project farms and that of the submissions were approximately the same. Differences in the distribution of diagnoses as well as recovered microorganisms were found, however, mainly related to the proportion of gastro-intestinal disorders and E. coli respectively. These proportions were negatively correlated. Overall the results showed that extrapolating diagnostic results of laboratory submissions to the population of farmed mink may be problematic, and more reliable methods for disease surveillance must be considered.  相似文献   

6.

Background

Aleutian mink disease virus (AMDV) is widespread among ranched and free-ranging American mink in Canada, but there is no information on its prevalence in other wild animal species. This paper describes the prevalence of AMDV of 12 furbearing species in Nova Scotia (NS), Canada.

Methods

Samples were collected from carcasses of 462 wild animals of 12 furbearing species, trapped in 10 NS counties between November 2009 and February 2011. Viral DNA was tested by PCR using two primer pairs, and anti-viral antibodies were tested by counterimmunoelectrophoresis (CIEP) on spleen homogenates.

Results

Positive PCR or CIEP samples were detected in 56 of 60 (93.3%) American mink, 43 of 61 (70.5%) short-tailed weasels, 2 of 8 (25.0%) striped skunks, 2 of 11 (18.2%) North American river otters, 9 of 85 (10.6%) raccoons, and 2 of 20 (10.0%) bobcats. Samples from six fishers, 24 coyotes, 25 red foxes, 58 beavers, 45 red-squirrels and 59 muskrats were negative. Antibodies to AMDV were detected by CIEP in 16 of 56 (28.6%) mink and one of the 8 skunks (12.5%). Thirteen of the mink were positive for PCR and CIEP, but three mink and one skunk were CIEP positive and PCR negative. Positive CIEP or PCR animals were present in all nine counties from which mink or weasel samples were collected.

Conclusions

The presence of AMDV in so many species across the province has important epidemiological ramifications and could pose a serious health problem for the captive mink, as well as for susceptible wildlife. The mechanism of virus transmission between wildlife and captive mink and the effects of AMDV exposure on the viability of the susceptible species deserve further investigation.  相似文献   

7.
《Integrative zoology》2017,12(3):186-197
The involvement of communities in ecological studies has been shown to augment conservation efforts, especially for cryptic species. However, there is a lack of studies addressing the utility of incidental sighting records from community members in gaining knowledge on habitat preferences and distribution of suitable habitat for these organisms. This study compares preferences of the Lumholtz's tree kangaroo (Dendrolagus lumholtzi ; LTK), a cryptic rainforest folivore in northeastern Australia, for various habitat and climatic variables derived from data collected during scientific projects to those derived from incidental sighting records using ArcGIS and Maxent. Incidental sighting records suggest that the species uses a wider range of altitudes, annual rainfalls, annual mean temperatures and vegetation types than predicted by scientific studies. Incidental records also show that the species can persist in areas of lower rainfall during the wettest month and lower minimum temperature during the coldest month. Both data place the species within a comparable range of rainfalls during the driest month, maximum temperatures of the warmest month and soil types. When using identified preferences to assess the extent and distribution of suitable habitat, incidental records predicted more areas of suitable habitat than scientific records with an overlap of up to 91% between them. The present study proves that incidental sighting records can be a valuable part of the study of cryptic species and should be considered complementarily alongside scientific studies to obtain comprehensive ecological information of a species that can assist in its conservation.  相似文献   

8.
Influenza A viruses (IAVs) are negative‐sense, single‐stranded and segmented RNA viruses of the Orthomyxoviridae family that may cause acute respiratory disease in a wide range of birds and mammals. Susceptibility of several species within the family Mustelidae to IAVs has been reported as a result of natural or experimental infections. The objectives of this study were to assess whether free‐ranging American mink populations from Northern Spain were infected with IAV and try to define the role of this species in the epidemiology of IAV. Sera from 689 American mink from Northern Spain captured between 2011 and 2014 were tested for the presence of antibodies against IAVs using a commercial competition cELISA. Positive sera were further analysed with haemagglutination inhibition (HI) assay. Fifteen of the 689 (2.2%, 1.3–3.6 CI95%) of the American minks analysed were ELISA positive. No significant differences were observed between years of capture, provinces, river basins, sexes or ages of the animals. All seropositive sera resulted negative to the panel strains used in the HI assay, showing that the most relevant strains circulating in swine, the most relevant avian subtypes (H5 and H7) and the H10N4 subtype isolated in minks have not been circulating in this free‐ranging exotic carnivore from Spain. In the light of these results, the free‐range American mink from Northern Spain do not seem to have an important role in the epidemiology of IAVs.  相似文献   

9.
Distemper vaccination of farmed fur animals in Finland   总被引：1，自引：0，他引：1  
The most important farmed fur animal species in Finland are the American mink (Mustela vison), blue fox (Alopex lagopus), silver fox (Vulpes vulpes) and raccoon dog (Nyctereutes procyonoides); all are susceptible to canine distemper. The only distemper vaccines currently available are for mink, although they also have been used for fox and raccoon dogs in emergency situations. The efficacy in eliciting neutralizing antibodies and the safety of three mink-distemper vaccines were studied under field conditions with mink and silver fox. Two of the vaccines were also studied with raccoon dogs and blue fox. All three vaccines elicited a satisfactory antibody response in mink, whereas the response varied in the other species. No side effects were observed in any species tested. One of the vaccines was safe and immunogenic in all four species.  相似文献   

10.
The East Balkan Swine (EBS) is the only indigenous pig breed in Bulgaria. We analyzed the mitochondrial DNA (mtDNA) control region and 21 microsatellite loci for 198 individuals from 11 farms in Bulgaria. Obtained 11 mtDNA haplotypes including three novel ones were grouped to two major clades, European clade E1 (146/198 individuals, 73.7%) and Asian clade A (52/198, 26.3%). The mixture of the two clades may have resulted from historical crossbreeding between the European and Asian pig breeds. Clade A was frequent in southeastern Bulgaria (Burgas Province), but less frequent or absent in northeastern Bulgaria (Varna and Shumen Provinces). The distribution of Europe- and Asia-specific haplotypes relative to EBS farm locations could be attributed to regional differences of breeding systems (e.g., crossbreeding with imported commercial pigs). A microsatellite analysis showed high heterozygosities for all the EBS farms, and negative inbreeding coefficients presumably due to crossing with commercial pigs or wild boars and/or efforts to reduce inbreeding by farmers. Bayesian clustering analyses showed that all farm populations are genetically well distinguishable from one another. Although diversity has been maintained by the efforts of farmers and a breeding association, the effective population size remains small, and conservation efforts should be continued.  相似文献   

11.
Limited funds for wildlife conservation require difficult choices about allocation of resources. One consideration is public preferences. While traditional attitudinal approaches can provide information about preferences for conservation efforts aimed at individual species, stated choice models offer a more suitable approach for exploring the complexity of public support across multiple species, through an examination of individuals’ choices in tradeoff situations. Using a survey in the American Southwest, we explored residents’ preferences for allocating funds for species based on factors that describe those species; species status, origin, and use. Species origin (native or non-native) and use (game or non-game) were more important as a whole than species status (declining, common, or extirpated). Further, respondents generally prioritized native (over non-native), game (over non-game), and declining (over common or extirpated). We discuss the implications of these findings for communication efforts aimed at generating public support and conservation decisions with complex tradeoffs.  相似文献   

12.
Antimicrobial agents are used extensively off‐label in mink, as almost no agents are registered for this animal species. Pharmacokinetic (PK) and pharmacodynamic (PD) data are required to determine antimicrobial dosages specifically targeting mink bacterial pathogens. The aims of this study were to assess, in a PKPD framework, the empirical dosage regimen for a combination of trimethoprim (TMP) and sulfadiazine (SDZ) in mink, and secondarily to produce data for future setting of clinical breakpoints. TMP and SDZ PK parameters were obtained experimentally in 22 minks following IV or oral administration of TMP/SDZ (30 mg/kg, i.e. 5 mg/kg TMP and 25 mg/kg SDZ). fAUC/MIC with a target value of 24 hr was selected as the PKPD index predictive of TMP/SDZ efficacy. Using a modeling approach, PKPD cutoffs for TMP and SDZ were determined as 0.062 and 16 mg/L, respectively. By incorporating an anticipated potentiation effect of SDZ on TMP against Escherichia coli and Staphylococcus delphini, the PKPD cutoff of TMP was revised to 0.312 mg/L, which is above the tentative epidemiological cutoffs (TECOFF) for these species. The current empirical TMP/SDZ dosage regimen (30 mg/kg, PO, once daily) therefore appears adequate for treatment of wild‐type E. coli and S. delphini infections in mink.  相似文献   

13.
Aleutian disease (Plasmacytosis) is caused by the Aleutian mink disease virus (AMDV), an autonomous parvovirus and affects many mustelid species, including the American mink (Neovisonvison). In Denmark, an eradication program reduced the prevalence of test-positive farms from 100% in 1976 to 15% in 1996. Nevertheless, the disease persists in the Vendsyssel district of Northern Jutland, despite the eradication efforts. In this study, we used spatial epidemiological analysis to test for spatial autocorrelation of the distribution of farms positive for the disease. We investigated 2375 farms in Denmark (342 of which were located in the Vendsyssel district), during the period 2000-2008. For the purpose of our study, a farm was considered positive when, on any test conducted in a year, at least three animals were tested positive. To detect spatial clusters, we performed a retrospective analysis with spatial scan statistics. We performed one analysis for each of the nine years (2000-2008). A separate analysis was conducted with only the farms in Vendsyssel included. The spatial cluster analysis revealed a significant cluster throughout the time period studied in Northern Jutland. The only exception was 2002 when an outbreak was detected in the southern part of Jutland, and not in the north. The farm-level prevalence of the disease in Denmark was highest in this year, suggesting that the outbreak in the south could have masked the persistent signal from the north; the northern cluster was still significant when analysing only the Vendsyssel populations. These results confirm that Northern Jutland continues to have a significantly higher number of cases than expected if the disease was randomly distributed.  相似文献   

14.
Posterior paresis/paralysis in farmed mink is responsible for significant morbidity and mortality, with individual farms reporting the loss of as many as 700 animals each year. Although this disease has been recognized by North American mink farmers for approximately 40 years, there are few published reports focusing on this entity. The objective of this study was to investigate the etiology and pathogenesis of the disease. Complete necropsy examinations were done on 40 clinically affected mink, ranging from 7 to 10 weeks of age, and on three normal animals in the same age range from two mink farms. Thirty-two of the 40 clinically affected animals had an isolated vertebral lesion characterized by bone lysis and proliferation that usually was centered on an intervertebral disk space in the midthoracic area. An inflammatory reaction, composed primarily of neutrophils, was present within the vertebral sections in 25 of the 40 affected animals (62.5%), and the presence of gram-positive cocci was confirmed in 8 of 10 animals (80%) in which bacterial organisms were observed histologically. Bacterial cultures from 15 affected animals yielded Streptococcus sp. from the intervertebral disk space in 13 of 15 (86.7%) animals and from heart blood in 6 of 8 (75%). A farm visit revealed no history or evidence of traumatic wounds as a source of infection in these animals, and the diet appeared to be adequate for skeletal development. We conclude that posterior paresis/paralysis in farmed mink is associated with bacterial diskospondylitis, likely occurring secondary to bacteremia/septicemia.  相似文献   

15.
The North Chinese leopard (Panthera pardus japonensis), the least-known big cat, disappeared in most historical range for decades, following the development of modern civilization. Unfortunately, we have scarce knowledge about the status of this big cat so far, apart from anecdotal reports. In this study, we investigated density, distribution, and habitat use of the leopard, the apex predator, in a complex forest landscape in the Loess Plateau. We used a camera-trapping network to obtain population estimates for leopards over 2 years through spatially explicit capture–recapture models. Our results, based on maximum likelihood and Bayesian/MCMC methods, reveal that the largest wild population of the leopard was found widely distributed in remnant forests in central Loess plateau. The population is increasing in our study area, and the density of leopards (1.70 (SE = 0.48) − 2.40 (SE = 0.67)/100 km2) is higher than other areas of China. According to the analysis of 2 seasonal occupancy models, prey species drive partially the leopard habitat use, predicting that the big cat thrives from the recovery of prey community. However, human disturbances, especially oil wells, seem to have negative impacts on the habitat use of leopards. Specifically, it is necessary to have joint efforts by the government and researchers to improve human disturbances management and prey species population density, as well as strengthen the investment in research on the North Chinese leopard, which could all further strengthen protection ability and ensure the long-term survival of this species.  相似文献   

16.
应用嗜肺性军团菌(Lp)共同抗原建立了微量间接血凝试验(MPHA),并以此方法对马鹿、梅花鹿、紫貂、水貂、貉、獭兔、熊、蓝狐、银狐及雉鸡等10种特种经济动物的830份血清样本进行了Lp抗体水平的检测。结果表明,紫貂和水貂血清的Lp抗体滴度1:32为阻抑试验阳性,而梅花鹿、马鹿、貉等8种特种经济动物血清的Lp抗体滴度1:64为阳性。按此标准,獭兔血清Lp抗体的阳性率为30.0％(9/30),梅花鹿15.3％(19/124),紫貂8.7％(2/23),马鹿8.45％(6/71),貉2.94％(6/204),水貂1.1％(8/273)。熊、蓝狐、银狐及雉鸡等血清样本全部呈阴性反应。  相似文献   

17.
Modern and paleoclimate changes may have altered species dynamics by shifting species’ niche suitability over space and time. We analyze whether the current genetic structure and isolation of the two large American felids, jaguar (Panthera onca) and puma (Puma concolor), are mediated by changes in climatic suitability and connection routes over modern and paleoclimatic landscapes. We estimate species distribution under 5 climatic landscapes (modern, Holocene, last maximum glaciations [LMG], average suitability, and climatic instability) and correlate them with individuals’ genetic isolation through causal modeling on a resemblance matrix. Both species exhibit genetic isolation patterns correlated with LMG climatic suitability, suggesting that these areas may have worked as “allele refuges.” However, the jaguar showed higher vulnerability to climate changes, responding to modern climatic suitability and connection routes, whereas the puma showed a continuous and gradual transition of genetic variation. Despite differential responsiveness to climate change, both species are subjected to the climatic effects on genetic configuration, which may make them susceptible to future climatic changes, since these are progressing faster and with higher intensity than changes in the paleoclimate. Thus, the effects of climatic changes should be considered in the design of conservation strategies to ensure evolutionary and demographic processes mediated by gene flow for both species.  相似文献   

18.
The activity and relative distribution of eight clinically important enzymes were measured in nine different organs in 10 healthy minks. Of the enzymes studied, OCT, ASAT and ALAT had higher absolute activities when compared to many other animals. This is believed to be adaptation to a high protein diet. OCT shows absolute liver specificity, and even ALAT is relatively liver specific in mink. SDH is found in relatively high concentrations in the liver as well as in the kidney. The organ distribution of the other enzymes investigated in mink – AP, CK, γ-GT and LD – is much the same as in many other animal species. Their clinical significance in serum is therefore the same.  相似文献   

19.
Hemorrhagic pneumonia is an acute and fatal disease of farmed mink caused by Pseudomonas aeruginosa. The pathogenesis of this disease has not yet been resolved. Mink are the only animals known to be susceptible to acute, contagious, and fatal lung infections caused by P. aeruginosa. The purpose of this study was to investigate the correlation between dose-response and season of infection and to clarify whether Danish mink are carriers of P. aeruginosa on their nasal mucosa during the season for hemorrhagic pneumonia. To elucidate the pathogenesis of the disease, an infectious dose-response trial was carried out on adult mink and mink kits, both in the season for hemorrhagic pneumonia (November) as well as out of season (July). It proved difficult to infect mink via the intra-nasal route. Only 4 out of 60 infected mink developed clinical disease and were euthanized, all of them in November, illustrating that predisposing factors in the mink itself and not infectious dose might be crucial for disease development. We were able to culture P. aeruginosa from the nasal cavity of the clinically healthy experimental mink 8 d after inoculation. This indicated that the mink can carry P. aeruginosa on their nasal mucosa without developing the disease. It was not possible, however, to culture P. aeruginosa from the nasal cavity of clinically healthy mink obtained from farms in November, which indicates that the organism is not a normal part of the nasal mucosal flora of mink.  相似文献   

20.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously 2019-nCoV) is suspected of having originated in 2019 in China from a coronavirus infected bat of the genus Rhinolophus. Following the initial emergence, possibly facilitated by a mammalian bridge host, SARS-CoV-2 is currently transmitted across the globe via efficient human-to-human transmission. Results obtained from experimental studies indicate that animal species such as cats, ferrets, raccoon dogs, cynomolgus macaques, rhesus macaques, white-tailed deer, rabbits, Egyptian fruit bats, and Syrian hamsters are susceptible to SARS-CoV-2 infection, and that cat-to-cat and ferret-to-ferret transmission can take place via contact and air. However, natural infections of SARS-CoV-2 have been reported only in pet dogs and cats, tigers, lions, snow leopards, pumas, and gorillas at zoos, and farmed mink and ferrets. Even though human-to-animal spillover has been reported at several instances, SARS-CoV-2 transmission from animals-to-humans has only been reported from mink-to-humans in mink farms. Following the rapid transmission of SARS-CoV-2 within the mink population, a new mink-associated SARS-CoV-2 variant emerged that was identified in both humans and mink. The increasing reports of SARS-CoV-2 in carnivores indicate the higher susceptibility of animal species belonging to this order. The sporadic reports of SARS-CoV-2 infection in domestic and wild animal species require further investigation to determine if SARS-CoV-2 or related Betacoronaviruses can get established in kept, feral or wild animal populations, which may eventually act as viral reservoirs. This review analyzes the current evidence of SARS-CoV-2 natural infection in domestic and wild animal species and their possible implications on public health.  相似文献   

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