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1.
To investigate the prevalence of Toxoplasma gondii infection in free-ranging Eurasian lynx (Lynx lynx) in Sweden, serosanguinous fluids and feces were collected from 207 carcasses of lynx killed or found dead from 1996 to 1998. Sera were tested for antibodies against T. gondii by the direct agglutination test, and 156 (75.4%) of the sera tested positive at antibody titers>or=40. Antibody prevalence was significantly lower in lynx originating from the northern parts of Sweden than in lynx from the more southern regions that are more densely populated by humans. Age-related differences also were found, with a significantly lower prevalence (55%) in juvenile (<1-yr-old) than in subadult and adult animals (82%). There was no significant difference in seroprevalence between males and females. Oocysts typical of T. gondii were not detected in any of the fecal samples.  相似文献   

2.
Thirty-seven carcasses of Eurasian lynx (Lynx lynx) collected and examined in Estonia during 1999-2001 had helminths. Parasites identified and their prevalence included Diphyllobothrium latum (5%), Taenia pisiformis (100%), Taenia laticollis (41%), Taenia hydatigena (3%), Taenia taeniaeformis (3%), Toxocara cati (68%), and Trichinella spp. (22%). The only significant relationships (P < or = 0.05) between occurrence of helminths and host age and sex were a greater number of T. pisiformis and T. laticollis in older than in youger male lynx, and older males had a greater number of species of helminth than did younger lynx. Sixty-one fecal samples collected during snow tracking of nine lynx were examined; eggs of T. cati were identified in 38 samples, and Capillaria spp were found in eight samples. This is the first systematic investigation of parasites of lynx in Estonia.  相似文献   

3.
Noninvasive methods using genetic markers have been suggested as ways to overcome difficulties associated with documenting the presence of elusive species. We present and assess a novel, reliable and effective molecular genetic technique for the unequivocal genetic identification of faeces from the endangered Iberian lynx (Lynx pardinus). From mitochondrial DNA (mtDNA) cytochrome b and D-loop region sequences, we designed four species-specific primers (for products 130-161 bp long) that were considered to be likely to amplify degraded DNA. We compared two DNA extraction methods, various DNA amplification conditions and the robustness and specificity of the primer pairs with 87 lynx samples from 5 potentially different lynx populations and with 328 samples of other carnivore species. The utility of the identification technique was tested with faeces of different ages, with faeces from controlled field experiments, and with faeces collected from locales with possible lynx populations from throughout the state of Andalusia, Spain (8052 km2). Faecal mtDNA extraction was more efficient using PBS wash of the faeces instead of a faeces homogenate. Our assay increased from 92.6 to 99% efficiency with a second amplification and a reduction in template concentration to overcome polymerase chain reaction (PCR) inhibition. Our assay never produced false positives, and correctly identified all lynx faeces. Of 252 faeces samples of unknown species collected throughout Andalusia, 26.6% (from three different areas) were classified as Iberian lynx, 1.4% showed evidence of PCR inhibition and 1.2% were of uncertain origin. This method has proven to be a reliable technique that can be incorporated into large-scale surveys of Iberian lynx populations and exemplifies an approach that can easily be extended to other species.  相似文献   

4.
As part of an ongoing restoration program in Colorado, USA, we evaluated adverse reactions and seroconversion in captive Canada lynx (Lynx canadensis) after vaccination with a recombinant F1-V fusion protein vaccine against Yersinia pestis, the bacterium that causes plague. Ten adult female lynx received the F1-V vaccine; 10 source- and age-matched lynx remained unvaccinated as controls. All of the vaccinated and control lynx remained apparently healthy throughout the confinement period. We observed no evidence of injection site or systemic reactions to the F1-V vaccine. Among vaccinated lynx, differences in log(10) reciprocal antibody titers measured in sera collected before and after vaccination (two doses) ranged from 1.2 to 5.2 for anti-F1 antibodies and from 0.6 to 5.2 for anti-V antibodies; titers in unvaccinated lynx did not change appreciably over the course of confinement prior to release, and thus differences in anti-F1 (P=0.003) and anti-V (P=0.0005) titers were greater among vaccinated lynx than among controls. Although our findings suggest that the F1-V fusion protein vaccine evaluated here is likely to stimulate antibody responses that may help protect Canada lynx from plague, we observed no apparent differences in survival between vaccinated and unvaccinated subject animals. Retrospectively, 22 of 50 (44%; 95% confidence interval 29-59%) unvaccinated lynx captured or recaptured in Colorado during 2000-08 had passive hemagglutination antibody titers >1:16, consistent with exposure to Y. pestis; paired pre- and postrelease titers available for eight of these animals showed titer increases similar in magnitude to those seen in response to vaccination, suggesting at least some lynx may naturally acquire immunity to plague in Colorado habitats.  相似文献   

5.
Last lynxes in Portugal? Molecular approaches in a pre-extinction scenario   总被引:1,自引:1,他引:0  
The Iberian lynx is the most threatened felidin the world and has suffered a declinethroughout its range. Effective monitoring ofthe species' presence is essential. Fieldwork inpreviously identified areas of lynx occurrencein Portugal has resulted in the collection of104 possible lynx scats. Recently, there hasbeen little or no evidence of lynx presence andscats could be confused with others from moreabundant carnivores such as wildcat, fox anddog. In order to confirm or not exclude thepresence of the species, identification ofscats was performed through the amplificationof lynx-specific mitochondrial DNA sequences.Two samples collected in Malcata NaturalReserve in 1997 were identified as lynx. Thisis the most recent and reliable proof of lynxpresence in Portugal*. Given the territorialbehavior of lynx, stable resident populationswould have produced a higher proportion ofpositively identified scats. Local extinctionsmight have taken place, and this genetic datasupports a suspected national pre-extinctionscenario for the species. Genetic analysisusing a non-invasive approach has proved to bean informative part of the lynx monitoringprogram. Technical problems faced and overcomeare also presented.  相似文献   

6.
In the multi-use landscape of southern Norway, the distribution of lynx is likely to be determined both by the abundance of their favoured prey – the roe deer – and the risk associated with the presence of humans because most lynx mortalities are caused by humans (recreational harvest, poaching, vehicle collisions). We described the distribution of the reproductive portion of the lynx population based on snow-track observations of females with dependent kittens collected over 10  yr (1997–2006) in southern Norway. We used the ecological-niche factor analysis to examine how lynx distribution was influenced by roe deer, human activity, habitat type, environmental productivity and elevation. Our first prediction that lynx should be found in areas of relatively high roe deer abundance was supported. However, our second prediction that lynx should avoid human activity was rejected, and lynx instead occupied areas more disturbed in average than those available (with the exception of the most densely occupied areas). Lynx, however, avoided the most disturbed areas and our third prediction of a trade-off between abundance of prey and avoidance of human activity was supported. On the one hand, roe deer in the most disturbed areas benefit to a large extent from current human land use practices, potentially allowing them to escape predation from lynx. On the other hand, the situation is not so favourable for the predators who are restricted in competition refuges with medium to low prey densities. The consequence is that lynx conservation will have to be achieved in a human modifed environment where the potential for a range of conflicts and high human-caused mortality will remain a constant threat.  相似文献   

7.
The feeding ecol ogy of the critically endangered Iberian lynxLynx pardinus Temminck, 1827, was studied in the most important remnant population, located in eastern Sierra Morena (Sierra de Andujar Natural Park, Spain). Three hundred sixty scats were collected from October 2001 through Sep tember 2002. RabbitsOryctolagus cuniculus dominated the lynx diet, as showed by frequency of occurrence (94%) and percent age of volume (91%). Red-legged partridgesAlectoris rufa were the most important secondary prey. No significant seasonal variation was observed regarding the diet preferences of the lynx. No difference was found in lynx diet by comparing two areas with high and low rabbit availability. Juvenile rabbits were positively selected when they were available, during late winter, spring and early summer.  相似文献   

8.
Information about reproductive physiology in the Eurasian lynx (Lynx lynx) would generate knowledge that could be useful in the management of the Swedish lynx population based on the knowledge about their reproductive potential and population development. Age-related differences in ovulation and implantation rates would affect the reproductive output and the development of the population. The aims of this study were to evaluate a protocol for collection of reproductive data from carcasses by comparisons with published field data and to generate data about reproduction in the Swedish lynx. Reproductive organs from 120 females that were harvested between March 1 and April 9 from 2009 to 2011 were collected and evaluated macroscopically for placental scars. Females had their first estrus as yearlings but did not have their first litter until the next season. Pregnancy rates were lower in 2-year-old females than in females aged 3 to 7 years but did not differ significantly from females aged 8 to 13 years (54.5%, 95.6%, and 75.0%, respectively). CL from the present season were morphologically distinctly different from luteal bodies from previous cycles (LBPC). All females ≥3 years had macroscopically visible LBPC, whereas only 67% of 22 to 23 months old females had one to three LBPC and no females <1 year of age had LBPC. Females aged 34 to 35 months had up to eight LPBC, whereas the highest number of LBPC counted in females ≥3 years of age was 11. These data would be in agreement with only one estrus per season and LBPC from at least three previous reproductive seasons in older females. The number of LBPC was significantly correlated with the weight of the ovaries rs = 0.648, P < 0.001) and the age of the animals (rs = 0.572, P < 0.001). Uterine weight differed significantly with the stage of the reproductive cycle and was highest for mature females in the luteal phase of the cycle. The estrous period, defined as occurrence of ovarian follicles lasted from March 5 to April 1 in this material. In conclusion, this study confirms that useful information about lynx reproduction can be collected from reproductive organs retrieved after the death of the animals. Continuous monitoring of lynx reproductive organs would therefore make a valuable contribution to collection of field data, gathering information that can be useful for the management of lynx populations and potentially for the lynx as an indicator of environmental disturbances.  相似文献   

9.
The epidemiology of Ancylostoma spp. was studied in the endangered Iberian lynx (Lynx pardinus) in the Do?ana National Park, south-west Spain. Faecal samples were collected throughout a complete annual cycle (August 1997 to September 1998). The overall egg prevalence of Ancylostoma spp. was 57.8%. The pattern of abundance of Ancylostoma spp. eggs in faeces was overdispersed. Juvenile lynx demonstrated a statistically higher prevalence and abundance of Ancylostoma spp. than in adults. These levels of egg output (maximum 21195 epg), as previously reported in free ranging large felid cubs, could be close to disease involvement. The potential pathogenicity of hookworms and the influence of individual and ecological factors on hookworm transmission in the Iberian lynx from the Do?ana National Park population are discussed.  相似文献   

10.
Diagnosis of pregnancies is an important management tool for the Iberian lynx Conservation Breeding Program, a program geared to recover the world's most endangered felid. Non-invasive methods such as fecal hormone analyses are not applicable to the lynx, since fecal progestin does not follow the typical pregnancy pattern of felids. Therefore, we aimed to test whether urine can be used as an alternative substance for pregnancy diagnosis in the Iberian lynx.Progesterone immunoreactive metabolites were determined in urine samples of pregnant and non-pregnant females before and during breeding season. Additionally, we used the Witness®Relaxin test to determine relaxin in blood and urine. No differences were found in progestin concentrations determined in urine samples collected from pregnant and non-pregnant animals between day 1 and 65 following mating. Although the Witness®Relaxin test was positive in serum samples collected from animals between day 32 and 56 of pregnancy, it failed in both fresh and frozen urine samples collected from the same stage of pregnancy. A weak relaxin reaction in urine samples collected from animals between day 29 and 46 of pregnancy was detectable after urines were concentrated by ultrafiltration (>50×). Concentrated samples obtained from non-pregnant and early pregnant animals yielded negative test results. In conclusion, the Witness®Relaxin test can be applied for pregnancy diagnosis in Iberian lynx in both serum and concentrated urine samples obtained during the second half of pregnancy. A positive relaxin test indicates an ongoing pregnancy, whereas negative tests must be judged carefully as hormone concentrations might be below detection thresholds.  相似文献   

11.
One hundred fecal samples were collected during research on Eurasian lynx ecology and food habits in the Polish part of the Bia?owieza Primeval Forest (BPF) from 2001 to 2006. Seventy-three percent of samples contained eggs or larvae of helminths. A total of 10 species of helminths was identified, including 3 Cestoda (Diphyllobothrium latum, Spirometra janickii, and unidentified species of Taeniidae), 1 Trematoda (Alaria alata), and 6 Nematoda (Aelurostrongylus abstrusus, Ancylostoma tubaeforme, Eucoleus aerophilus, Metastrongylus sp., Nematodirus sp., and Toxocara cati). Alaria alata has not been reported previously in lynx. A statistical comparison of the 2 techniques used to isolate eggs, i.e., flotation and sedimentation, indicates that sedimentation was more effective.  相似文献   

12.

Dispersal is a key process for the maintenance of intraspecific genetic diversity by ensuring gene flow within and between populations. Despite the ongoing expansion of large carnivores in Europe, lynx populations remain fragmented, isolated, and threatened by inbreeding and loss of genetic diversity. In the course of large carnivore monitoring in the Czech Republic, several biological samples of Eurasian lynx were collected outside the permanent occurrence of this species. Using microsatellite genotyping we identified these as four dispersing lynx males and applied multiple methods (Bayesian clustering in STRUCTURE, Principal Component Analysis (PCA), frequency-based method in GENECLASS2, and machine-learning framework in assignPOP) to assign them to possible source populations. For this we used genotypes from five European lynx populations: the Bohemian-Bavarian-Austrian (N?=?36), Carpathian (N?=?43), Scandinavian (N?=?20), Baltic (N?=?15), and Harz (N?=?23) population. All four dispersers were successfully assigned to different source populations within Europe and each was recorded at a distance of more than 98 km from the edge of the distribution of the source population identified. Such movements are among the longest described for lynx in Central Europe to this point. The findings indicate the ability of lynx males to disperse in human-dominated landscape thus facilitation of these movements via creation and/or protection of potential migratory corridors together with protection of dispersing individuals should be of high importance in conservation of this iconic predator in Central Europe.

  相似文献   

13.
Serum samples from 106 Eurasian lynx (Lynx lynx) from across Sweden, found dead or shot by hunters in 1993-99, were investigated for presence of antibodies to feline parvovirus (FPV), feline coronavirus, feline calicivirus, feline herpesvirus, feline immunodeficiency virus, Francisella tularensis, and Anaplasma phagocytophila, and for feline leukemia virus antigen. In addition, tissue samples from 22 lynx submitted in 1999 were analyzed by real-time polymerase chain reaction (PCR) to detect nucleic acids specific for viral agents and A. phagocytophila. Except for FPV antibodies in one lynx and A. phagocytophila in four lynx, all serology was negative. All PCR results also were negative. It was concluded that free-ranging Swedish lynx do not have frequent contact with the infectious agents considered in this study.  相似文献   

14.
The european lynx (Lynx lynx) might be expected to have a high intake of radiocaesium in the parts of Sweden where the main prey of the lynx, namely reindeer and roe deer have high activity concentrations of radiocaesium because of high ground deposition. We have measured 137Cs in muscle samples from 733 lynx during 1996–2003. The aim was to quantify the extent to which radiocaesium is transferred from fallout deposition to lynx, to test whether the transfer was higher in areas where there are reindeer present, to see if there was any decline in radiocaesium over time, and to calculate the radiation dose to lynx. Most samples were collected in central and northern Sweden during January–April. Activity concentrations in lynx varied from 13 Bq kg–1 to about 15 kBq kg–1 fresh weight, with the highest value corresponding to a radiation dose at 18 mGy/year. Aggregated transfer coefficients (Tag), calculated by dividing the 137Cs activity concentration in lynx muscle by the average ground deposition (total from Chernobyl and nuclear weapon tests) within a 50 km radius around the location of the lynx, varied from 0.004 to 1.3 m2 kg–1 and were significantly higher within the reindeer herding area than outside. The concentration ratio (CR) for lynx/reindeer was 2.6 on average, whilst the average for lynx/roe deer outside the reindeer herding area was lower at 1.3. Based on these results, a CR of around 2 could be considered representative for the general ratio between predator and prey. A long-term decline of radiocaesium in prey species was reflected in lynx, with an effective half-life of 7 years from 1996 to 2003. The study shows that the accumulation of radiocaesium in predators, especially predators of reindeer, makes them more vulnerable to high radiocaesium deposition than most other wild species.  相似文献   

15.
Abstract In March 2000, Canada lynx (Lynx canadensis) were listed as a federally threatened species in 14 states at the southern periphery of their range, where lynx habitat is disjunct and snowshoe hare (Lepus americanus) densities are low. Forest conditions vary across lynx range; thus, region-specific data on the habitat requirements of lynx are needed. We studied lynx in northern Maine, USA, from 1999 to 2004 to assess quality and potential for forests in Maine to sustain lynx populations. We trapped and radiocollared 43 lynx (21 M, 22 F) during this period and evaluated diurnal habitat selection by 16 resident adult lynx (9 M, 7 F) monitored in 2002. We evaluated lynx selection of 8 habitats at multiple spatial scales, and related lynx habitat selection to snowshoe hare abundance. Lynx preferred conifer-dominated sapling stands, which supported the highest hare densities on our study site (x̄ = 2.4 hares/ha), over all other habitats. The habitats where lynx placed their home ranges did not differ by sex. However, within their home ranges, males not only preferred conifer-dominated sapling stands, but also preferred mature conifer, whereas females singularly preferred conifer-dominated sapling stands. Approximately one-third of Maine's spruce-fir forest and nearly 50% of our study area was regenerating conifer or mixed-sapling forest, resulting from a disease event and intensive forest management (e.g., large clear-cuts). Our findings suggest that current habitat conditions in Maine are better than western montane regions and approach conditions in boreal forests during periods of hare abundance. We recommend that forest landowners maintain a mosaic of different-aged conifer stands to ensure a component of regenerating conifer-dominated forest on the landscape.  相似文献   

16.
Specimens of gastric mucosa and liver of 25 free-ranging Eurasian lynx (Lynx lynx), and four red foxes (Vulpes vulpes) shot in Sweden during 1999-2000, were investigated for the presence of Helicobacter species. Histopathology, bacteriologic culture and urease test, Helicobacter genus-specific 16S rDNA PCR analysis, and DNA sequence analysis were applied. Numerous Helicobacter-like organisms were observed histologically in the gastric mucosa of one fox. Helicobacter spp. were detected in the stomach by PCR analysis in 17 (68%) of the lynx and in three (75%) of the foxes. Seven of the positive lynx were also positive in the urease test. PCR fragments, amplified from lynx and foxes, were sequenced and compared with those of known Helicobacter species. PCR products from lynx were closely related (>or=98% homology) to H. heilmannii, and PCR fragments from foxes demonstrated close homology to H. heilmannii and H. salomonis. No Helicobacter spp. or Helicobacter-like organisms could be cultured. The PCR analysis of the liver was negative for all animals. The pathologic significance of the presence of Helicobacter spp. in the stomach of free-ranging lynx and foxes remains uncertain.  相似文献   

17.
Various species of large predators are reported to influence each other through interference or exploitation competition that may affect demography and survival of the subordinate species. We analyzed spatial relationships between grey wolf (Canis lupus) and Eurasian lynx (Lynx lynx) in Białowieża Primeval Forest (BPF, eastern Poland) to determine how they partitioned the space. The wolves (= 8) and lynx (n = 14) were radio-tracked in 1991–1999. Three wolves and seven lynx were radio-tracked simultaneously in 1994–1996. Territories of wolf packs and home ranges of lynx overlapped considerably (76% of wolf territories and 50% of lynx home ranges, on average). In three cases, their core areas were also overlapping. Wolf-lynx dyads with overlapping home ranges were simultaneously located at distances from 0 to 28 km from each other. We found neither avoidance nor attraction between wolves and lynx occupying the same areas. We concluded that in BPF, the two large predators coexist due to specialization on different preferred prey and heterogeneous habitat.  相似文献   

18.
Abstract The Eurasian lynx (Lynx lynx) causes large loss of free-ranging domestic sheep in Norway. We tested whether the observed higher kill rates by male lynx than female lynx were related to an association between the availability of the main natural prey, as measured by roe deer (Capreolus capreolus) habitat suitability, presence of sheep, and habitat selection of male and female lynx. We found that lynx selected areas with high roe deer suitability during summer and winter. Moreover, during summer, compared to male lynx, females had greater selection for roe deer areas and a stronger avoidance for sheep grazing areas, which suggests that previously observed differences in kill rates between male and female lynx can be attributed to sex-specific habitat use during summer. The connection between lynx habitat use and roe deer also was reflected in a positive relationship between the roe deer suitability of a sheep grazing area and the total loss of lambs, which suggests that livestock, rather than being actively selected, are mainly killed by lynx incidentally when encountered during other lynx activities (e.g., searching for natural prey species). Therefore, any management practice that separates lynx and sheep, such as concentrating livestock into small patches or less preferred habitats, may reduce depredation.  相似文献   

19.
Aim To relate the recent Iberian lynx decline to changes in the distribution of the European rabbit after the haemorrhagic disease outbreak of 1989. As Iberian rabbits evolved in two geographically separated lineages, being the recent lynx range practically restricted to the southwestern lineage, we also test if differential range dynamics exists for these lineages, with the consequent implications for lynx conservation and reintroduction planning. Location The Iberian Peninsula. Methods We modelled environmental favourability for the lynx based on its distribution before 1989, and for the rabbit using distribution data collected primarily after 1989, and validated them using independent abundance data. We compared both models and combined them in a lynx occurrence forecast. We correlated the prevalence of southwestern rabbit lineage with the environmental favourability for the rabbit. Results The environmental lynx model correlated with past lynx abundance data, but did not reflect its recent strong range contraction. The rabbit model correlated with recent rabbit abundance, but was negatively correlated with the environmental model for the lynx. The combination of both models forecasted lynx occurrence in a few separated nuclei, which encompass all recent lynx records. The prevalence of rabbit's southwestern lineage correlated negatively with favourability for the rabbit. Main conclusions The region to which the lynx became confined before 1989 is currently less favourable for rabbits, whereas more favourable areas remain outside lynx reach. This differential favourability correlates with rabbit phylogeographical structure, suggesting that the southwestern lineage is facing more unfavourable conditions or is less resilient to recent diseases. The loss of concordance between lynx distribution and the whole rabbit phylogeographical structure has prevented lynx persistence in northeastern rabbit lineage areas, which should be considered in lynx reintroduction planning. Similar conservation problems could affect other ecologically interacting species whose distributions’ overlapping has sharply diminished.  相似文献   

20.
During the last two centuries, lynx populations have undergone severe declines and extinctions in Europe. The Alpine lynx, once distributed across the whole Alpine arc, became extinct due to direct human prosecution and deprivation of its main prey in the 1930s. Similar to the Iberian lynx Lynx pardinus , its taxonomy has been subject to several controversies. Moreover, knowing the taxonomic status of the Alpine lynx will help to define conservation units of extant lynx populations in Europe. In this study, we investigated two mitochondrial DNA regions in museum specimens ( n =15) representing the autochthonous Alpine population and in samples from extant Eurasian lynx Lynx lynx populations in Europe and Asia ( n =17). Phylogenetic analysis (cytochrome b , 345 bp) placed the Alpine lynx within the Eurasian lynx lineage. Among all individuals examined, seven different haplotypes (control region, 300 bp) were observed but no unique Alpine haplotype was discovered. Haplotypes of the extinct Alpine population were identical to previously described haplotypes in Scandinavian lynx signifying a recent genetic ancestry with current European populations. Moreover, our genetic data suggest two distinct glacial refugia for the Carpathian and Balkan population. Overall this study demonstrates that historical DNA from extinct populations can help to disentangle the phylogenetic relationships and historical biogeography of taxa with only a limited number of extant populations remaining.  相似文献   

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