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1.
Using the parasitological washing out method, we examined the intestines of 428 red foxes (Vulpes vulpes) for the presence of Echinococcus multilocularis (Leuckart 1863) and found that the overall prevalence was 2.6% (confidence interval 95% 1.3–4.5%). This is the first extended research reporting on the presence of E. multilocularis in the Slovenian fox population.  相似文献   

2.
The prevalence of Sarcocystis sp. was assessed in foxes from northern Croatia (city of Varadin). The intestine of 50 (29 male and 21 female) foxes aged 1–5 years, killed during the rabies control campaign, were examined. Sarcocystis sp. was identified in 62% of the fox intestinal samples examined. There was no sex difference in the rate of invasion. However, the rate of invasion differed significantly between the animals aged 1 year (47%), and those aged 2 (71%) and 3–5 years (71%).  相似文献   

3.
The raccoon dog (Nyctereutes procyonoides) is an East Asian Canid that has been introduced in Europe. Introduction of alien species is an increasing conservation issue. We examined the diet of a recently established raccoon dog population in Denmark by analysing stomach content in 249 carcasses collected in 2008–2016. Raccoon dog diet was compared to the diet of native badger (Meles meles) and red fox (Vulpes vulpes) in Denmark. The most common food for raccoon dogs were invertebrates (frequency of occurrence, FO 69%), small mammals (FO 68%), birds (FO 41%), fruits (FO 38%), amphibians (FO 36%) and carrions (FO 34%). The occurrence of invertebrates was highest during spring and summer, while fruits, cereals and carrions were eaten most often during autumn and winter. As expected, raccoon dog shared the major food categories with badger and red fox, but generally, it had a wider dietary niche. Overall, dietary overlap between raccoon dog and badger was 0.74 (Pianka index, Ojk). The dietary overlap with red fox was relatively high in all seasons, peaking in summer (Ojk 0.87) and dropping in winter (Ojk 0.79). Despite the dietary overlap between the alien racoon dog and native red fox and badger, the species may coexist due to partitioning of feeding habitats and/or because the red fox is limited by other factors, e.g. diseases and anthropogenic activities. The introduced raccoon dog seems to fit a dietary niche between badger and red foxes in human-dominated landscapes in north-western Europe.  相似文献   

4.

Background

Salmonella spp. have been isolated from a wide range of wild animals. Opportunistic wild carnivores such as red foxes (Vulpes vulpes) and badgers (Meles meles) may act as environmental indicators or as potential sources of salmonellosis in humans. The present study characterizes Salmonella spp. isolated from the intestinal contents of hunted or dead red foxes (n?=?509) and badgers (n?=?17) in northern Italy.

Findings

Thirty-one strains of Salmonella belonging to 3 Salmonella enterica subspecies were isolated. Fourteen different serovars of S. enterica subsp. enterica were identified, among which were serovars often associated with human illness.

Conclusions

Wild opportunistic predators can influence the probability of infection of both domestic animals and humans through active shedding of the pathogen to the environment. The epidemiological role of wild carnivores in the spread of salmonellosis needs to be further studied.
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5.
We investigate the feeding responses of the red fox (Vulpes vulpes) at a regional scale to different densities of European wild rabbit (Oryctolagus cuniculus) in central–southern Spain. Rabbit abundance indices were obtained in 86 localities during summer 2002. The diet of the fox was studied by analysis of 114 scats collected in 47 of these localities. The feeding response of the fox was examined by a representation of the dry weight percent of rabbit in the diet as a function of the abundance of rabbits; this used data only from those localities where at least 3 scats were collected (70 fox scats from 18 localities). We evaluated the relationship between rabbit abundance and the diversity of the diet of the fox. The feeding patterns of red foxes approximated to Holling’s type III functional response, typical of opportunistic predators. There was a negative relationship between the diversity of the fox’s diet and the abundance of rabbits. Therefore, the fox apparently behaves as a facultative predator, feeding on rabbits when they are abundant and shifting to other prey (and hence a more diverse diet) when rabbits are scarce. These findings are the first step towards understanding the potential role of red foxes in regulating rabbit populations in central–southern Spain.  相似文献   

6.
A non-invasive genetic approach has been recently employed in the population genetics of wild species, using faeces that could be easily collected, particularly of elusive or endangered species. However, faeces of pine (Martes martes) and beech marten (M. foina) can be morphologically similar and could be confused with those of polecat (Mustela putorius) and red fox (Vulpes vulpes). On this basis, a rapid, simple and inexpensive RFLP protocol using a cytochrome b (Cyt b) gene fragment of mtDNA, isolated from faecal samples, was performed to distinguish the above-mentioned species.  相似文献   

7.
Toxoplasma gondii is an intracellular parasite able to both promote and inhibit apoptosis. T. gondii renders infected cells resistant to programmed cell death induced by multiple apoptotic triggers. On the other hand, increased apoptosis of immune cells after in vivo infection with T. gondii may suppress the immune response to the parasite. Glycosylphosphatidylinositol (GPI)-anchored proteins dominate the surface of T. gondii tachyzoites and GPIs are involved in the pathogenicity of protozoan parasites. In this report, we determine if GPIs are responsible for inhibition or induction of host cell apoptosis. We show here that T. gondii GPIs fail to block apoptosis that was triggered in human-derived cells via extrinsic or intrinsic apoptotic pathways. Furthermore, characteristics of apoptosis, e.g. caspase-3/7 activity, phosphatidylserine exposition at the cell surface or DNA strand breaks, were not observed in the presence of T. gondii GPIs. These results indicate that T. gondii GPIs are not involved in survival or in apoptosis of host cells. This absence of effect on apoptosis could be a feature common to GPIs of other parasites.  相似文献   

8.
Over the last 40 years, the red fox has spread into the tundra zone, which coincided with its population increase in European Russia. Foxes become more abundant from the northeast southwestward according to zonal regularities. Their population density is the highest in the southern taiga, the subtaiga, and partly in the forest tundra of the Kola Peninsula. The distribution of foxes depends on the abundance of their prey. Nevertheless, the ratio of forested to open areas, mosaic and habitat fragmentation, as well as forest structure, also play an important role. The best ratios between habitat areas have been determined. The red fox is an ecotone species. Human impact on forest habitats caused an increase in its population and its wide expansion into the taiga.  相似文献   

9.
10.
An examination was made of fluoride content in the mandibular first molars of the permanent teeth of the red fox Vulpes vulpes living in north-west (NW) Poland. The teeth were first dried to a constant weight at 105°C and then ashed. Fluorides were determined potentiometrically, and their concentrations were expressed in dry weight (DW) and ash. The results were used to perform an indirect estimation of fluoride pollution in the examined region of Poland. The collected specimens (n = 35) were classified into one of the three age categories: immature (im, 6–12 months), subadult (subad, from 12 to 20 months) and adult (ad, >20 months). The mean concentrations (geometric mean) of fluoride were similar in the im and subad groups (230 and 296 mg/kg DW and 297 and 385 mg/kg ash, respectively), and significantly smaller than in the ad group (504 and 654 mg/kg, respectively, in DW and ash). Basing on other reports that the ∼400 mg/kg DW concentration of fluoride in bones in the long-lived wild mammals generally reflects the geochemical background, it was found that 57% of the foxes in NW Poland exceeded this value by 9% to 170%. This indirectly reflects a moderate fluoride contamination in the tested region.  相似文献   

11.
Identifying correctly trophic interactions is important for understanding population dynamics and ecosystem functioning. However, some predator–prey relationships may still remain undetected, due to the difficulty of observing rare predation events. We report the first observation of predation of arctic fox (Vulpes lagopus) pups by common ravens (Corvus corax). The predation event was witnessed on Bylot Island, Nunavut, Canada, through an automatic camera placed on a den. On June 8, 2013, the day following pup emergence from the den, the complete litter of four was killed and taken away by a pair of ravens despite the intermittent presence of the mother. This event lasted 2.5 h, occurred during a low lemming year, and resulted in the fox pair failing their reproduction. Only two other fox litters were present that summer in our 600 km2 study area, so this litter predated by ravens accounted for 25 % (4/16) of the pups produced. Our report shows how continuous monitoring of dens using automatic cameras can allow documentation of rare events. In addition to food competition and cache raiding, pup predation contributes to the antagonistic interactions between arctic foxes and ravens in the High Arctic, which may intensify during low lemming years. This observation allows a better understanding of species interactions within the Arctic predator guild.  相似文献   

12.
Dense granule protein-7 (GRA-7) is an excretory protein of Toxoplasma gondii. It is a potential serodiagnostic marker and vaccine candidate for toxoplasmosis. Previous reports demonstrated that GRA-7 induces innate immune responses in macrophages by interacting with TRAF6 via the MyD88-dependent pathway. In the present study, we evaluated the antiviral activity and induction of an antiviral state by GRA-7 both in vitro and in vivo. It was observed that GRA-7 markedly reduced the replication of vesicular stomatitis virus (VSV-GFP), influenza A virus (PR8-GFP), coxsackievirus (H3-GFP), herpes simplex virus (HSV-GFP), and adenovirus-GFP in epithelial (HEK293T/HeLa) and immune (RAW264.7) cells. These antiviral activities of GRA-7 were attributed to the induction of type I interferon (IFN) signaling, resulting in the secretion of IFNs and pro-inflammatory cytokines. Additionally, in BALB/c mice, intranasal administration of GRA-7 prevented lethal infection by influenza A virus (H1N1) and exhibited prophylactic effects against respiratory syncytial virus (RSV-GFP). Collectively, these results suggested that GRA-7 exhibits immunostimulatory and broad spectrum antiviral activities via type I IFN signaling. Thus, GRA-7 can be potentially used as a vaccine adjuvant or as a candidate drug with prophylactic potential against viruses.  相似文献   

13.
In the period of August 2013 to September 2015, we collected and measured the body weight of 246 red fox (Vulpes vulpes) carcasses collected during hunts. A portion of these red foxes (n = 153) was originally from habitats they shared with the golden jackal (Canis aureus), while the other portion (n = 93) had almost no contact with this species. We analyzed the body weight of red foxes from both areas according to age (adult-cub) as well as gender. We have found that the younger animals that live sympatrically with the golden jackal weigh less than those from the golden jackal-free territory regardless of gender. In the case of adult red foxes, the habitat-related differences between body weight were found to be insignificant. These results suggest that the high level of nutritional niche overlap between sympatric red fox and golden jackal could affect the body weight of juvenile red foxes.  相似文献   

14.

Background

Toxoplasma gondii is a widespread occurring parasite infecting warm-blooded animals, including pigs and humans. The aims of this study were to estimate the prevalence of anti-T. gondii antibodies and to evaluate risk factors for T. gondii seropositivity in breeding pigs raised in Estonia. Sera from 382 pigs were tested with a commercial direct agglutination test, using a cut-off titer of 40 for seropositivity, for the presence of anti-T. gondii immunoglobulin G antibodies.

Results

Twenty-two (5.8%) of the 382 pigs tested seropositive for T. gondii, and 6 of the 14 herds had at least one seropositive pig. The proportion of seropositive pigs within the herds ranged between 0 and 43%. Gender appeared as a significant factor, with sows having 5.6 times higher odds to be seropositive to T. gondii than boars. Seroprevalence did not increase with age.

Conclusions

Anti-T. gondii antibodies were present in a substantial proportion of breeding pig herds in Estonia. On the other hand, the presence of herds without seropositive pigs illustrates that porcine T. gondii infections can be avoided even in a country where the parasite is endemic and common in several other host species.
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15.
The diet of the red fox Vulpes vulpes was investigated in five regions of northeastern Poland by stomach content analysis of 224 foxes collected from hunters. The red fox is expected to show the opportunistic feeding habits. Our study showed that foxes preyed mainly on wild prey, with strong domination of Microtus rodents, regardless of sex, age, month and habitat. Voles Microtus spp. were found in 73% of stomachs and constituted 47% of food volume consumed. Other food items were ungulate carrion (27% of volume), other mammals (11%), birds (9%), and plant material (4%). Sex- and age-specific differences in dietary diversity were found. Adult males and juvenile foxes had larger food niche breadths than adult females and their diets highly overlapped. Proportion of Microtus voles increased from autumn to late winter. Significant habitat differences between studied regions were found. There was a tendency among foxes to decrease consumption of voles with increasing percentage of forest cover. Based on our findings, red foxes in northeastern Poland can be recognized as a generalist predators, consuming easily accessible and abundant prey. However, high percentage of voles consumed regardless of age, sex, month, or habitats may indicate red fox specialization in preying on Microtus rodents.  相似文献   

16.
Wan J  Bai X  Liu W  Xu J  Xu M  Gao H 《Molecular biology reports》2009,36(6):1299-1303
Prion diseases are fatal neurodegenerative disorders of humans and certain other mammals. Prion protein gene (Prnp) is associated with susceptibility and species barrier to prion diseases. No natural and experimental prion diseases have been documented to date in Arctic fox. In the present study, coding region of Prnp from 135 Arctic foxes were cloned and screened for polymorphisms. Our results indicated that the Arctic fox Prnp open reading frame (ORF) contains 771 nucleotides encoding 257 amino acids. Four single nucleotide polymorphisms (SNPs) (G312C, A337G, C541T, and A723G) were identified. SNPs G312C and A723G produced silent mutations, but SNPs A337G and C541T resulted in a M–V change at codon 113 and R–C at codon 181, respectively. The Arctic fox Prnp amino acid sequence was similar to that of the dog (XM 542906). In short, this study provides preliminary information about genotypes of Prnp in Arctic fox.  相似文献   

17.
The swift fox Vulpes velox Say, 1823, a small canid native to shortgrass prairie ecosystems of North America, has been the subject of enhanced conservation and research interest because of restricted distribution and low densities. Previous studies have described distributions of the species in the southern Great Plains, but data on density are required to evaluate indices of relative abundance and monitor population trends. We examined regressions of swift fox density (estimated by mark-recapture) on timed-track surveys, scat surveys, and catch-per-unit effort indices. Seventy-nine swift foxes (42 male, 37 female) were captured 151 times during 10 240 trapnights between May 2003 and December 2004 in the Panhandle of Oklahoma, USA. Density estimates, based on mark-recapture data from autumn 2004, were 0.08–0.44 foxes/km2. Survey indices explained 51 to 76% of the variation in estimates of fox density. Our study indicates that surveys of time-to-track encounters and scat deposition rates show promise in monitoring trends in population abundance over large areas.  相似文献   

18.
One-thousand eight-hundreds forty-five individuals were examined for the presence of Toxoplasma gondii antibodies, 31.3 % prevalence of them being found by using the complement fixation test as a screening method. The determined total antibodies were present mainly in low titers which show evidence of past or latent infection. The acute stage of toxoplasmosis by the detection of specific IgM and IgA was diagnosed. The occurrence of acute toxoplasmosis in the healthy population is very low and presents only at 0.3 %. There was no significant difference between genders (p = 0.232), but significant differences in the prevalence of toxoplasmosis depending on age (p < 0.001) and regions (p = 0.007) were found.  相似文献   

19.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

20.
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