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1.
Widespread distribution of livestock in the natural habitats of large carnivores may negatively impact carnivore populations by reducing wild prey availability and increasing human–carnivore conflicts. In this study, we used camera-trapping data collected in the temperate forests of the Taihang Mountains in North China during 2016–2019 to examine whether and how free-ranging cattle affected habitat use and Diel activity patterns of the endangered North Chinese leopard (Panthera pardus japonensis) and its 2 wild prey species, Siberian roe deer (Capreolus pygargus), and wild boar (Sus scrofa). Residents were also interviewed to record livestock depredation events by leopards during 2015–2019. We found that roe deer spatially avoided sites frequented by cattle, but wild boar did not. In the growing seasons, leopards shared habitats with cattle and tended to increase their diurnal activities where cattle were present. All 3 study species exhibited fine-scale spatial-temporal segregation to cattle. Leopards selectively preyed on calves over adult cattle and livestock depredation frequency was positively correlated with the detection rates of cattle and wild prey, but not that of leopard. These findings not only show that through behavioral adaption large carnivores and their ungulate prey may persist under livestock disturbance, but also highlight how important proper livestock management is for conserving North Chinese leopards in this region. To enhance livestock management and mitigate human–leopard conflicts, we recommend specific actions, such as better guarding of free-ranging cattle or adoption of a captive farming system.  相似文献   

2.
Stable isotope analysis is very useful in animal ecology, especially in diet reconstruction and trophic studies. Differences in isotope ratios between consumers and their diet, termed discrimination factors, are essential for studies of stable isotope ecology and are species‐specific and tissue‐specific. Given the specialized bamboo diet and clear foraging behavior, here, we calculated discrimination factors for carbon and nitrogen isotopes from diet to tissues (tooth enamel, hair keratin and bone collagen) for the giant panda (Ailuropoda melanoleuca), a species derived from meat‐eating ancestors. Our results showed that carbon discrimination factor obtained from giant panda tooth enamel (ε 13Cdiet‐enamel = 10.0‰) and nitrogen discrimination factors from hair keratin (Δ15Ndiet‐hair = 2.2‰) and bone collagen (Δ15Ndiet‐collagen = 2.3‰) were lower, and carbon discrimination factors from hair keratin (Δ13Cdiet‐hair = 5.0‰) and bone collagen (Δ13Cdiet‐collagen = 6.1‰) were higher than those of other mammalian carnivores, omnivores and herbivores. Such distinctive values are likely the result of a low‐nutrient and specialized bamboo diet, carnivore‐like digestive system and exceptionally low metabolism in giant pandas.  相似文献   

3.
In most monogamous breeding systems males demonstrate a high degree of paternal care. With the significant costs of this parental investment, it is clearly in the interests of males to raise only their own offspring. It has therefore been predicted, but never observed in the field, that if the female of a monogamous male is promiscuous, he will desert her and attempt to breed with an alternative female. Here we report a case of such a mate desertion in the aardwolf Proteles cristatus. We suggest, however, that mate desertion should occur only rarely in response to female promiscuity. This is because a cuckolded male may still be raising some of his own offspring, and should desert only on the rare occasions when an alternative receptive female is exclusively available to himself.  相似文献   

4.
The explosive accumulation of mammalian genomes has provided a valuable resource to characterize the evolution of the Y chromosome. Unexpectedly, the Y‐chromosome sequence has been characterized in only a small handful of species, with the majority being model organisms. Thus, identification of Y‐linked scaffolds from unordered genome sequences is becoming more important. Here, we used a syntenic‐based approach to generate the scaffolds of the male‐specific region of the Y chromosome (MSY) from the genome sequence of 6 male carnivore species. Our results identified 14, 15, 9, 28, 14 and 11 Y‐linked scaffolds in polar bears, pacific walruses, red pandas, cheetahs, ferrets and tigers, covering 1.55 Mbp, 2.62 Mbp, 964 Kb, 1.75 Mb, 2.17 Mbp and 1.84 Mb MSY, respectively. All the candidate Y‐linked scaffolds in 3 selected species (red pandas, polar bears and tigers) were successfully verified using polymerase chain reaction. We re‐annotated 8 carnivore MSYs including these 6 Y‐linked scaffolds and domestic dog and cat MSY; a total of 11 orthologous genes conserved in at least 7 of the 8 carnivores were identified. These 11 Y‐linked genes have significantly higher evolutionary rates compared with their X‐linked counterparts, indicating less purifying selection for MSY genes. Taken together, our study shows that the approach of synteny search is a reliable and easily affordable strategy to identify Y‐linked scaffolds from unordered carnivore genomes and provides a preliminary evolutionary study for carnivore MSY genes.  相似文献   

5.
Evidence suggests that religion is an important driver of peoples’ attitudes toward nature, but the link between religion and carnivore conservation is poorly understood. We examined peoples’ attitudes in Buddhist (= 83) and Muslim communities (= 111) toward snow leopards (Panthera uncia) and wolves (Canis lupus) in Ladakh, India. We found that the effect of religion on attitudes was statistically nonsignificant, and was tempered by gender, education, and awareness of wildlife laws. Even though religion by itself was not an indication of an individual’s attitude toward large carnivores, the extent to which he/she practiced it (i.e., religiosity) had a positive correlation with pro-carnivore attitudes in the case of Buddhist but not Muslim communities. Our findings indicate that it may be useful to integrate locally relevant religious philosophies into conservation practice. However, the emphasis of conservation messaging should vary, stressing environmental stewardship in the case of Islam, and human–wildlife interdependence in the case of Buddhism.  相似文献   

6.
Subsistence pastoralists often view large carnivores negatively given that any loss of livestock is likely to represent a significant economic cost. Consequently, large carnivore conservation initiatives in rural landscapes should incorporate appropriate human–carnivore conflict mitigation strategies. In this study, structured interviews with local residents (n = 247) were used for determining attitudes toward African wild dogs (Lycaon pictus) among rural communities neighboring two protected areas in KwaZulu-Natal, South Africa. Contrary to expectations, the majority of respondents (58%) were generally positive toward wild dogs. This was probably due to a lack of livestock depredation by wild dogs and relatively high levels of formal education among respondents. Respondents with greater knowledge of wild dogs and conflict mitigation had more positive attitudes, and most were aware of effective husbandry techniques. The positive attitudes observed in these rural communities may benefit wild dog dispersal from natal home ranges and the future conservation of this endangered carnivore.  相似文献   

7.
Predator–prey size relationships are among the most important patterns underlying the structure and function of ecological communities. Indeed, these relationships have already been shown to be important for understanding patterns of macroevolution and differential extinction in the terrestrial vertebrate fossil record. Stable isotope analysis (SIA) is a powerful remote approach to examining animal diets and paleodiets. The approach is based on the principle that isotope compositions of consumer tissues reflect those of their prey. In systems where resource isotope compositions are distributed along a body size gradient, SIA could be used to reconstruct predator–prey size relationships. We analyzed stable carbon isotope distributions amongst mammalian herbivores in extant and Plio–Pleistocene African savanna assemblages, and show that the range of δ13C values among mammalian prey species (herbivores and rodents) increases with body mass (BM), because C4 plant feeding (essentially grazing) is more common among larger taxa. Consequently, δ13C values of mammalian carnivores in these systems are related to species' BM, reflecting a higher average C4 prey component in the diets of larger‐bodied carnivores. This pattern likely emerges because only the largest carnivores in these systems have regular access to the C4 prey base, whereas smaller carnivores do not. The δ13C–BM relationship observed in mammalian carnivores is a potentially powerful approach for reconstructing and parameterizing predator–prey size relationships in contemporary and fossil savanna assemblages, and for interpreting how various behavioral, ecological and environmental factors influence prey size selection.  相似文献   

8.
Taste 2 receptors (TAS2R) mediate bitterness perception in mammals, thus are called bitter taste receptors. It is believed that these genes evolved in response to species‐specific diets. The giant panda (Ailuropoda melanoleuca) and red panda (Ailurus fulgens styani) in the order Carnivora are specialized herbivores with an almost exclusive bamboo diet (>90% bamboo). Because bamboo is full of bitter tasting compounds, we hypothesized that adaptive evolution has occurred at TAS2R genes in giant and red pandas throughout the course of their dietary shift. Here, we characterized 195 TAS2R genes in 9 Carnivora species and examined selective pressures on these genes. We found that both pandas harbor more putative functional TAS2R genes than other carnivores, and pseudogenized TAS2R genes in the giant panda are different from the red panda. The purifying selection on TAS2R1, TAS2R9 and TAS2R38 in the giant panda, and TAS2R62 in the red panda, has been strengthened throughout the course of adaptation to bamboo diet, while selective constraint on TAS2R4 and TAS2R38 in the red panda is relaxed. Remarkably, a few positively selected sites on TAS2R42 have been specifically detected in the giant panda. These results suggest an adaptive response in both pandas to a dietary shift from carnivory to herbivory, and TAS2R genes evolved independently in the 2 pandas. Our findings provide new insight into the molecular basis of mammalian sensory evolution and the process of adaptation to new ecological niches.  相似文献   

9.
To investigate the relationship between faecal calcium (Ca) and phosphorus (P) excretion in different mammalian species, a meta‐analysis on digestibility data derived from the literature was conducted. Seventy‐three studies on carnivores, omnivores, large and small hindgut fermenters, ruminants and hippos (a total of 21 mammalian species, precondition for inclusion dietary Ca/P ratio 1.5/1 – 3.0/1) were analysed for Ca and P digestibility. Dietary Ca/P ratios were lower than faecal Ca/P ratios in carnivores, omnivores, ruminants and hippos. In hindgut fermenters, dietary Ca/P ratios were higher than faecal Ca/P ratios, indicating higher intestinal Ca absorption in these species. In all species investigated, there was a significant positive relationship between Ca intake and faecal Ca excretion and between P intake and faecal P excretion. In the biologically relevant range, these equations predicted lower faecal Ca losses in hindgut fermenters than ruminants, for faecal P vice versa. In all species, faecal Ca and P excretion correlated significantly. In carnivores, this highly linear correlation was exceptionally strong (R² = .92). Yet, the linearity of the correlation was questionable in omnivores and ruminants. Possibly, the strong linear correlation of faecal Ca and P excretion in carnivores is due to the formation of insoluble Ca/P complexes in their relatively short and simple gastrointestinal tract. Another hypothesis is that in carnivores, Ca homeostasis relies on modifying bone turnover to a higher degree than on changes in intestinal Ca absorption. For the formation of bone matrix, a constant ratio of Ca and P absorption is of advantage.  相似文献   

10.
We used a four-day program with a pre-test–post-test approach on 355 selected school children to investigate the influence of a wildlife education project on the acquisition of knowledge about large carnivores in Loliondo, Tanzania. After the school program was completed, a significantly higher number of school children correctly identified six carnivore species, compared to when the same identification task was administered prior to the initiation of the school program. This increased knowledge is important for the conservation of large carnivores in general and of African wild dogs, in particular, because the post-test results showed that most school children considered wild dogs to be an important part of the ecosystem. In areas experiencing human– carnivore conflict, it is important to include conservation education programs in school curricula as early as possible to enable students to gain knowledge of large carnivores and their role in ecosystems.  相似文献   

11.
We conducted 300 semi-structured interviews with local people adjacent to Tarangire National Park, northern Tanzania, to determine their attitudes and perceptions toward large carnivores. We analyzed the relationships between attitudes and age, gender, education, occupation, years at residence, income, distance from protected area, livestock owned, livestock lost to predators and knowledge of carnivores. Three-quarters of respondents (79%) held negative attitudes toward large carnivores, while 20% were generally positive. Three variables were positively associated with attitudes towards different species: formal education (all carnivore species), years at residence (lions and cheetahs), and knowledge of carnivores (cheetahs). Attitudes toward large carnivores were not significantly related to distance from protected area, livestock owned. or livestock lost to predators. Findings suggested that interventions aimed at fostering positive attitudes toward large carnivores should focus on improving formal education and securing long-term residency for people in the region.  相似文献   

12.
13.
Pathogen surveillance in free-ranging carnivores presents challenges due to their low densitie and secretive nature. We combined molecular and serological assays to investigate infections by viral pathogens (Canine parvovirus (CPV), Canine distemper virus (CDV) and Canine coronavirus (CCoV)) in Portuguese carnivores (Canis lupus, Vulpes vulpes, Lutra lutra, Martes foina, M. martes, Meles meles, and Genetta genetta) over a period of 16 years. Additionally we explored spatio-temporal patterns of virus occurrence in Canis lupus. Our study identified CPV DNA in all carnivore species with an overall prevalence of 91.9 %. CPV was detected in all sampled years and seasons in Canis lupus, supporting its enzootic nature. CDV RNA was mainly detected in the Canidae family, with viral nucleic acid recorded between 2005 and 2008 with a peak prevalence of 67 % among the wolf population, followed by a sharp decline, suggesting an epizootic behaviour of the virus. Antibodies show that mustelids and viverrids were often exposed to CDV. CCoV was first recorded by molecular methods in wolf samples in 2002, remaining in the wolf populations with marked fluctuations over time. The dual serological and molecular approach provided important epidemiological data on pathogens of wild carnivores in Portugal. These programmes should also include monitoring of other potential reservoir hosts such as domestic cats and dogs.  相似文献   

14.
Introduction: The mammalian digital end organ has developed in three basic functional forms, i.e., claw, hoof and nail. Whereas detailed information on the ontogeny and phylogeny of the equine and bovine hooves, and the human nail, respectively, are on hand, such data are still not available for the canine claw. Because phylogenetically the carnivore claw is considered as a primary form of digital end organ, data on the organogenesis of the canine claw will complement current knowledge on onto‐ and phylogeny of the carnivore claw, and digital end organs in general. Materials and Methods: Light and electron microscopy of 18 canine fetuses of 40–150 mm crown‐rump‐length and five puppies aged 1 day–4 weeks post‐partum. Results: The development of the canine claw can be divided into four periods. The first stage is initiated by the differentiation of the connective tissue layers of the claw anlage. The second stage is characterized by formation of the specific claw shape, and the third stage by further regional function‐related modifications resulting in the development of the five different segments of the digital end organ. The fourth stage proceeds post‐natally when the influence of increasing body weight and weight bearing leads to the final functional adaptation of the papillary body. Conclusion: The organogenesis of the canine claw resembles that of the feline claw in many aspects, but also shows some specific deviations. In particular, the development of the dorsal ridge – characteristic for the carnivore claw – differs between both species. The results of our study therefore raise the question whether the current hypothesis on allocation of the different segments of the canine claw has to be reconsidered.  相似文献   

15.
Plants produce nutritious, fleshy fruits that attract various animals to facilitate seed dispersal and recruitment dynamic. Species-specific differential selection of seed size by multiple frugivorous disperser assemblages may affect the subsequent germination of the ingested seeds. However, there is little empirical evidence supporting this association. In the present study, we documented conflicting selection pressures exerted on seed size and germination by five frugivorous carnivores on a mammal-dispersed pioneer tree, the date-plum persimmon (Diospyros lotus), in a subtropical forest. Fecal analyses revealed that these carnivores acted as primary seed dispersers of D. lotus. We also observed that seed sizes were selected based on body mass and were species-specific, confirming the “gape limitation” hypothesis; three small carnivores (the masked palm civet Paguma larvata, yellow-throated marten Martes flavigula, and Chinese ferret-badger Melogale moschata) significantly preferred to disperse smaller seeds in comparison with control seeds obtained directly from wild plants whereas the largest Asiatic black bears (Ursus thibetanus) ingested larger seeds. Seeds dispersed by medium-sized hog badgers (Arctonyx albogularis) were not significantly different from control seeds. However, regarding the influence of gut passage on seed germination, three arboreal dispersal agents (martens, civets, and bears) enhanced germination success whereas terrestrial species (ferret-badgers and hog badgers) inhibited the germination process compared with undigested control seeds. These conflicting selection pressures on seed size and germination may enhance the heterogeneity of germination dynamics and thus increase species fitness through diversification of the regeneration niche. Our results advance our understanding of seed dispersal mechanisms and have important implications for forest recruitment and ecosystem dynamics.  相似文献   

16.
This article assessed the patterns and determinants of human-carnivore conflicts and local attitudes toward carnivores in 18 villages in eastern Isfahan Province, Central Iran. Livestock depredation by carnivores was common, representing a total loss of 3% and 13% of sheep and poultry population, respectively. Over 93% depredation events were attributed to the gray wolf. Households and herders held negative attitudes toward the gray wolf due to their perceived threat to livestock and humans and expressed positive attitudes toward other carnivore species. Preventative measures, such as improved livestock husbandry seem to reduce damage caused by carnivores. In general, livestock that were herded by day with the presence of shepherds and guardian dogs and kept within an enclosure at night with dog presence were 35% less likely to be killed by wild predators. Education influenced peoples’ attitudes toward carnivores.  相似文献   

17.
The question of how Sarcocystis neurona is able to overcome species barrier and adapt to new hosts is central to the understanding of both the evolutionary origin of S. neurona and the prediction of its field host range. Therefore, it is worth reviewing current knowledge on S. neurona host specificity. The available host range data for S. neurona are discussed in relation to a subject of evolutionary importance—specialist or generalist and its implications to understand the strategies of host adaptation. Current evidences demonstrate that a wide range of hosts exists for S. neurona. This parasite tends to be highly specific for its definitive host but much less so for its intermediate host (I.H.). The unique specificity of S. neurona for its definitive host may be mediated by a probable long coevolutionary relationship of the parasite and carnivores in a restricted ecological niche ‘New World’. This might be taken as evidence that carnivores are the ‘original’ host group for S. neurona. Rather, the capacity of S. neurona to exploit an unusually large number of I.H. species probably indicates that S. neurona maintains non-specificity to its I.H. as an adaptive response to insure the survival of the parasite in areas in which the ‘preferred’ host is not available. This review concludes with the view that adaptation of S. neurona to a new host is a complex interplay that involves a large number of determinants.  相似文献   

18.
Background – Canine pyodermas associated with meticillin‐resistant Staphylococcus spp. (MRS) have increased in prevalence over the past decade. Hypothesis/Objectives – To compare the prevalence of MRS isolation from dogs with superficial pyoderma at a primary care clinic (PCC) and those at a tertiary care facility (VMTH) in California, USA, and identify associated risk factors. Animals – Client‐owned dogs from the VMTH (80 dogs) and the PCC (30 dogs). Methods – Aerobic bacterial culture and antibiotic susceptibility were performed on swab specimens collected from dogs, and meticillin resistance was determined using microdilution methods according to Clinical and Laboratory Standards Institute guidelines. A mecA gene PCR assay was used to confirm meticillin resistance when possible. Results – Of 89 staphylococcal isolates from the VMTH, 34 (38.2%) were meticillin resistant. In 31 dogs, pyoderma persisted, and one or more follow‐up isolates were obtained. The species isolated and drug susceptibility changed unpredictably during treatment. Of 33 PCC isolates, nine (27.3%) were meticillin resistant. Multiple drug resistance was identified in 41 of 53 (77.3%) MRS isolates from the VMTH and five of nine from the PCC. The sensitivity and specificity of PCR for the detection of meticillin resistance was 34 of 39 (87%) and 86 of 87 (99%), respectively. Risk factors for meticillin resistance for both sites were antibiotic treatment within the last year (P = 0.001), and for VMTH, hospitalization of dogs within the last year (P = 0.001). Conclusions and clinical importance – The prevalence of meticillin resistance was not different between VMTH and PCC isolates (P = 0.29). Previous antimicrobial therapy was an important risk factor for the isolation of MRS at both sites.  相似文献   

19.
AIMS: To assess whether stoats (Mustela erminea) would eat small baits containing 0.1% sodium monofluoroacetate (1080); whether they would die from it; how long it would take to kill them; and to document the behaviour of 1080-intoxicated stoats.

METHODS: Stoats were offered 1-g baits of two semi-fluid formulations containing 0.1% 1080, presented in open dishes, and their subsequent behaviour was monitored by video and direct observation. Muscle samples from stoats that died were analysed for 1080 residues.

RESULTS: There was no significant difference between two types of bait with regard to acceptance, mortality, and time to death, and behavioural effects were similar; consequently, results from the two types of bait were combined. Twelve of 14 stoats offered the baits ate them voluntarily, and a 13th licked bait off its fur; all 13 died between 1 h 15 min and 4 h 7 min (mean 2 h 38 min) later. At first (range 29 min — 2 h 7 min, mean 1 h 1 min), their behaviour appeared to be normal. Ataxia and hyperactivity were the first behavioural signs of poisoning, and lasted 2 min — 1 h 40 min (mean 26 min). This was followed by recumbency with convulsions and rapid breathing (range 16 min to 2 h, mean 58 min), then recumbency with limited activity and progressively shallow breathing prior to death (range 1–51 min, mean 33 min). Stoats became non-responsive to a light being turned on, or to touch once recumbency became sustained.

Residues of 1080 were found in muscle tissue of all 13 dead stoats, at concentrations ranging from 0.075 μg/g in a 287-g male that died 4 h 7 min after eating only 0.74 g of bait, to 2.5 μg/g in a 254-g female that died 2 h 42 min after taking a whole 1-g bait.

CONCLUSION: Stoats will voluntarily take small (1-g) baits containing a lethal dose of 1080 at 0.1%, and die from it comparatively rapidly for a mammalian carnivore.  相似文献   

20.
The Iberian lynx, (Lynx pardinus), is the most endangered felid in the world. To determine whether sympatric carnivores are reservoirs of pathogens posing a disease risk for the lynx, evidence of exposure to 17 viral, bacterial and protozoan agents was investigated in 176 carnivores comprising 26 free-living lynx, 53 domestic cats, 28 dogs, 33 red foxes (Vulpes vulpes), 24 Egyptian mongooses (Herpestes ichneumon), 10 common genets (Genetta genetta) and 2 Eurasian badgers (Meles meles) in the areas inhabited by the last two populations of Iberian lynx, both in Andalusia (South-Western Spain).The results indicated that the lynx had low rates of contact with viral pathogens, with one seropositive finding each for feline leukemia virus, parvovirus and canine adenovirus-1, whereas contact with bacteria and protozoa appeared more frequent. Active infections with parvovirus, Ehrlichia spp., Mycobacterium bovis, Leptospira interrogans and Cytauxzoon spp. were confirmed. In contrast, 53% of the domestic cats were exposed to some infectious agent (prevalence range 4.5–11.4%). Antibodies to canine distemper virus and parvovirus were frequently found in dogs (32% and 42%, respectively) and foxes (30% and 12%). Past or present infections with parvovirus, Ehrlichia spp., Chlamydophila spp., M. bovis, Salmonella enterica, L. interrogans, Toxoplasma gondii, and Neospora caninum were also detected in these and other species surveyed.Questionnaires to owners revealed that 14% of the dogs but none of the cats had been vaccinated, and no cat had been neutered. Based on the apparent absence of acquired immunity of the lynx against infectious agents, the frequent detection of agents among sympatric carnivores, and the reported lack of immunocompetence of the Iberian lynx, a disease outbreak among the local abundant carnivores may pose a serious disease risk for lynx conservation.  相似文献   

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