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1.
Serum samples from 894 wild animals (representing 31 species) from Trinidad and Grenada were examined by the microscopic agglutination test for leptospiral antibodies; 198 were positive. These included 39 bats, 88 mongooses, six opossums, 10 peridomestic rodents, 15 forest rodents, 10 lizards, and 30 toads. Thirteen pathogenic serogroups were involved. Thirty-nine Leptospira isolates were reported from mongooses, opossums, rodents and toads.  相似文献   

2.
Bovine tuberculosis (Tb) occurs in cattle and in wildlife, with various species infected in a range of countries. The control or eradication of Tb can be empirically based or based on understanding of disease processes such as described in mathematical models. The eradication of Tb from Australia was largely empirically based, with water buffalo (Bubalus bubalis) apparently being the only significant wildlife disease host. Buffalo populations were apparently greatly reduced to achieve Tb eradication. This paper examines the alternative approach of basing control or eradication on mathematical models, and compares some predictions of one-host (wildlife) and two-host (cattle and wildlife) disease models with empirical data on Tb in both cattle and in wildlife. The one-host and two-host models were based on those published and also derived. For example, reported positive regressions between prevalence’s of Tb in cattle and in brushtail possums in New Zealand and also between prevalence’s of Tb in red deer and in brushtail possums in New Zealand, are consistent with two-host disease models assuming frequency dependent transmission. However most models of Tb in wildlife, e.g. the Barlow models, assume density dependent transmission. The implications for disease eradication are that models assuming density dependent transmission have a threshold host (wildlife) density about zero. Hence, if frequency dependent, not density dependent, transmission actually occurs, then host (wildlife) density would have to be reduced much lower, in order for eradication of Tb from cattle.  相似文献   

3.
To identify the animal sources for Cryptosporidium contamination, we genotyped Cryptosporidium spp. in wildlife from the watershed of the New York City drinking water supply, using a small-subunit rRNA gene-based PCR-restriction fragment length polymorphism analysis and DNA sequencing. A total of 541 specimens from 38 species of wildlife were analyzed. One hundred and eleven (20.5%) of the wildlife specimens were PCR positive. Altogether, 21 Cryptosporidium genotypes were found in wildlife samples, 11 of which were previously found in storm runoff in the watershed, and six of these 11 were from storm water genotypes of unknown animal origin. Four new genotypes were found, and the animal hosts for four storm water genotypes were expanded. With the exception of the cervine genotype, most genotypes were found in a limited number of animal species and have no major public health significance.  相似文献   

4.
The mean annual litterfall at two dry woodland sites in central Queensland was 1129 kg ha–1 for an open E. populnea F. Muell. woodland (n = 2 years), and 2318 kg ha–1 for a woodland dominated by E. cambageana Maiden (n = 1 year). Leaves formed the largest component of total litterfall, which varied seasonally with a spring–summer maximum. Annual litterfall at these sites conformed with a pattern of decreasing litter production with declining annual rainfall, consistent with a range of eucalypt-dominated communities.  相似文献   

5.
The epidemiological and historical aspects of some important and representative wildlife diseases from Scandinavia are discussed. In noninfectious diseases, examples include cataract in moose (Alces alces), atherosclerosis in hybrid hares (Lepus timidus X L. europaeus), and ethmoid tumors in moose. The epizootiological and historical aspects of the recent epizootics of myxomatosis in European rabbits (Oryctolagus cuniculus) and rabies and sarcoptic mange in red foxes (Vulpes vulpes) are reviewed. The decline and subsequent increase in population abundances of tetraonids including the capercaillie (Tetrao urogallus), black grouse (Lyrurus tetrix), and hazel hen (Tetrastes bonasia) are discussed, and an hypothesis on predation by foxes is presented as a possible explanation for these population fluctuations. The potential impact of environmental pollution on wildlife populations is emphasized with reference to mercury in wildlife from Sweden and the possible effects of cadmium and selenium resulting from acidification. A bibliography of important references is presented pertaining to these and other diseases of wildlife from Scandinavia.  相似文献   

6.
Postmortem records of wild-living birds in Norway with laboratory-confirmed findings of salmonella infection were summarized for the period from 1969 to 2000. Salmonella spp. were isolated from 470 birds belonging to 26 species. The salmonella-positive birds included 441 small passerines, 15 gulls, 5 waterfowl, 4 birds of prey, 3 doves, and 2 crows. The bullfinch (Pyrrhula pyrrhula) was by far the most frequently recorded species (54% of the cases). Salmonella enterica serover Typhimurium was recovered from all cases except from one hooded crow (Corvus corone), which yielded serovar Paratyphi-B var. Java. Variant O:4,12 comprised 96% (451 cases) of all serovar Typhimurium isolates, including all the passerines, while variant O:4,5,12 accounted for the remaining 4% (18 cases). The occurrence of salmonellae in small passerines showed a distinct seasonality, with a peak in February and March. Plasmid profile analysis of 346 isolates of serovar Typhimurium O:4,12 detected six profiles, of which two comprised 66 and 28% of the isolates, respectively. Phage typing of 52 randomly selected isolates of serovar Typhimurium O:4,12 from passerines detected four types: DT 40 (54%), U277 (35%), DT 99 (6%), and DT 110 (4%).  相似文献   

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Cannon L. R. G. 1978. A larval ascaridoid nematode from Queensland scallops. International Journal for Parasitology8: 75–80. The morphology of a fourth stage larval ascaridoid found in Amusium balloti is given with observations on the double nature of the excretory system. The infection rate was 5.6% with rarely more than one worm per scallop. No seasonal change in incidence was detected and no change in incidence with host size. The systematic position, possible life cycle and economic importance of the worm are discussed.  相似文献   

10.
Serengeti lions frequently experience viral outbreaks. In 1994, one-third of Serengeti lions died from canine distemper virus (CDV). Based on the limited epidemiological data available from this period, it has been unclear whether the 1994 outbreak was propagated by lion-to-lion transmission alone or involved multiple introductions from other sympatric carnivore species. More broadly, we do not know whether contacts between lions allow any pathogen with a relatively short infectious period to percolate through the population (i.e. reach epidemic proportions). We built one of the most realistic contact network models for a wildlife population to date, based on detailed behavioural and movement data from a long-term lion study population. The model allowed us to identify previously unrecognized biases in the sparse data from the 1994 outbreak and develop methods for judiciously inferring disease dynamics from typical wildlife samples. Our analysis of the model in light of the 1994 outbreak data strongly suggest that, although lions are sufficiently well connected to sustain epidemics of CDV-like diseases, the 1994 epidemic was fuelled by multiple spillovers from other carnivore species, such as jackals and hyenas.  相似文献   

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Bovine tuberculosis, caused by Mycobacterium bovis, is a pathogen of growing concern in free-ranging wildlife in Africa, but little is known about the disease in Tanzanian wildlife. Here, we report the infection status of Mycobacterium bovis in a range of wildlife species sampled from protected areas in northern Tanzania. M. bovis was isolated from 11.1% (2/18) migratory wildebeest (Connochaetes taurinus) and 11.1% (1/9) topi (Damaliscus lunatus) sampled systematically in 2000 during a meat cropping program in the Serengeti ecosystem, and from one wildebeest and one lesser kudu (Tragelaphus imberbis) killed by sport hunters adjacent to Tarangire National Park. A tuberculosis antibody enzyme immunoassay (EIA) was used to screen serum samples collected from 184 Serengeti lions (Panthera leo) and 19 lions from Ngorongoro Crater sampled between 1985 and 2000. Samples from 212 ungulates collected throughout the protected area network between 1998 and 2001 also were tested by EIA. Serological assays detected antibodies to M. bovis in 4% of Serengeti lions; one positive lion was sampled in 1984. Antibodies were detected in one of 17 (6%) buffalo (Syncerus caffer) in Tarangire and one of 41 (2%) wildebeest in the Serengeti. This study confirms for the first time the presence of bovine tuberculosis in wildlife of northern Tanzania, but further investigation is required to assess the impact on wildlife populations and the role of different wildlife species in maintenance and transmission.  相似文献   

14.
Queensland     
《BMJ (Clinical research ed.)》1911,1(2631):1346-1347
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15.
Neosporosis, which is caused by the coccidian parasite Neospora caninum, is recognized as a major disease of domestic animals that causes high abortion rates in cattle and fatal neurological disease in dogs. A life cycle of N. caninum in wild animals (i.e. sylvatic) has long been suspected because neosporosis has been detected in several wildlife species. Recently, the transmission of N. caninum has been confirmed in coyotes and white-tailed deer. The newly confirmed wild hosts and other wild animals are probably involved in the sylvatic cycle of the parasite. Control measures for neosporosis could now become more complicated, given the participation of wildlife in the life cycle of N. caninum.  相似文献   

16.
Selected overheated substrates commercially available for public use in sub-tropical Queensland, Australia were screened for the presence of Thermoactinomyces species using an air sampler. All substrates with the exception of tea tree mulch were found to contain Thermoactinomyces species. Subsequent 16S rDNA oligonucleotide sequencing of the selected eight isolates indicated that some of these species were closely related to previously reported allergenic Thermoactinomyces vulgaris and Laceyella sacchari. In view of this, the isolates were tested to determine their adhesion ability and cytotoxicity to human lung cells (calu-3 cells). The results indicated that all eight isolates were highly adherent and showed cytotoxicity to this cell line. These findings might indicate that the presence of such species in overheated agricultural materials may constitute a public health risk if storage and handling conditions are not optimal and do not meet criteria defined for sub-tropical climates.  相似文献   

17.
Microbial communities play an important role in organismal and ecosystem health. While high‐throughput metabarcoding has revolutionized the study of bacterial communities, generating comparable viral communities has proven elusive, particularly in wildlife samples where the diversity of viruses and limited quantities of viral nucleic acid present distinctive challenges. Metagenomic sequencing is a promising solution for studying viral communities, but the lack of standardized methods currently precludes comparisons across host taxa or localities. Here, we developed an untargeted shotgun metagenomic sequencing protocol to generate comparable viral communities from noninvasively collected faecal and oropharyngeal swabs. Using samples from common vampire bats (Desmodus rotundus), a key species for virus transmission to humans and domestic animals, we tested how different storage media, nucleic acid extraction procedures and enrichment steps affect viral community detection. Based on finding viral contamination in foetal bovine serum, we recommend storing swabs in RNAlater or another nonbiological medium. We recommend extracting nucleic acid directly from swabs rather than from supernatant or pelleted material, which had undetectable levels of viral RNA. Results from a low‐input RNA library preparation protocol suggest that ribosomal RNA depletion and light DNase treatment reduce host and bacterial nucleic acid, and improve virus detection. Finally, applying our approach to twelve pooled samples from seven localities in Peru, we showed that detected viral communities saturated at the attained sequencing depth, allowing unbiased comparisons of viral community composition. Future studies using the methods outlined here will elucidate the determinants of viral communities across host species, environments and time.  相似文献   

18.
Sustainable use of wildlife: The view from archaeozoology   总被引:1,自引:0,他引:1  
The concept of “sustainable use” is a polemic, especially when referring to wildlife and other “natural resources.” Claims vary from persistent overuse to traditional practices of sustaining the resource base. Arguments for either side routinely draw from contemporary situations, relying on relatively short time periods. But, if the notion “sustainable” is to be consequential, the period under consideration must be meaningful – claims that trends over a few years or even decades are representative of long-term phenomena are questionable, for they depend on numerous untested, if not untestable, assumptions. Research in anthropology, biology, biological conservation, ecology, policy, restoration ecology, social development, and wildlife management is routinely constrained to relatively short time periods, and such results are of limited value for evaluating sustainable use. Archaeozoology provides unique tools for investigating trends in human-resource relations over periods of centuries and millennia; it is one of the few disciplines explicitly dedicated to the study of material evidence over significant time periods that bears directly on the question of sustainable use. Hence, objective, scientific evaluation of sustainable use must contemplate archaeozoological evidence.Yet, archaeozoology often does not provide definitive answers: it is wrought with fundamental problems in sampling, data gathering, analysis, and interpretation (e.g., varying screen sizes; meta-sampling procedures; comparisons across diverse spatial, temporal, and environmental continua; etc.). Typically data must be evaluated through inference, rather than through direct observations and experiments. Moreover, environmental variation (e.g., climate change, sea level change, tectonic movement, etc.), as well as changes in societies, confounds the interpretation of long-term human–environmental trends. But, those challenges are not unique to archaeozoology, for biological and ecological phenomena are no less subject to multiple sources of environmental and social variation. The difference is that archaeologists are patently cognizant of these sources of variability, and they openly debate them when interpreting data, while in other disciplines these sources of change are routinely ignored. Nonetheless, despite the unique relevance of their work, few archaeozoologists have ventured outside their discipline to engage natural scientists and policy makers in issues of biological conservation and wildlife biology, and particularly the root questions of sustainable use. In addition to considering data and hypotheses regarding long-term prehistoric human–wildlife interactions, it is essential to view this information within broader perspectives, linked to other disciplines as well as to contemporary social and policy issues. Because sustainable use is mandated in international instruments and national policies, the notion has relevance in arenas far beyond academia, where archaeozoologists must be integrated into interdisciplinary teams.  相似文献   

19.
Blood was collected from selected wildlife species in specific areas of Alaska (USA) during 1976-96. A modified agglutination test was used to test sera for evidence of exposure to Toxoplasma gondii. Serum antibody prevalence was 43% (62 positive of 143 tested) for black bears (Ursus americanus), 9% (11/125) for wolves (Canis lupus), 7% (22/319) for Dall sheep (Ovis dalli), 6% (14/241) for caribou (Rangifer tarandus), 1% (3/240) for moose (Alces alces), and 1% (2/241) for bison (Bison bison). A predictive model was developed to determine the effect of sex, age, location, and year of collection on antibody prevalence for each species. Prevalence was higher in older black bears, caribou, and wolves. For black bears, prevalence was highest in the southeast region of the state. For caribou, prevalence was lowest on the Alaska Peninsula.  相似文献   

20.
Wildlife trade is the very heart of biodiversity conservation and sustainable development providing an income for some of the least economically affluent people and it generates considerable revenue nationally. In Asia the unsustainable trade in wildlife has been identified as one of the main conservation challenges. Internationally, wildlife trade is regulated through the Convention on International Trade in Endangered Species of wild fauna and flora (CITES) to which all Southeast Asian nations are signatory. I obtained data on international trade in CITES-listed animals in the period 1998–2007. In all >35 million animals (0.3 million butterflies; 16.0 million seahorses; 0.1 million other fish; 17.4 million reptiles; 0.4 million mammals; 1.0 million birds) were exported in this period, 30 million (~300 species) of them being wild-caught. In addition 18 million pieces and 2 million kg of live corals were exported. Malaysia, Vietnam, Indonesia and China are the major exporters of wild-caught animals and the European Union and Japan are the most significant importers. Over this period exports in birds significantly decreased, trade in the other taxa either increased or remained stable. For all taxa but butterflies the vast majority of individuals represent wild-caught individuals. Records of illegal or undeclared international trade are scant but can be significantly larger than levels of official exports. It is concluded that there is an urgent need for better assessments of what levels of exploitation are sustainable (including exploring appropriate proxies for Non Detriment Findings), for initiatives to make regulatory mechanisms more effective (including the introduction of minimum mandatory standards and monitoring selected wildlife trade hubs), and for better licensing and registration. Funding for at least some of these initiatives can be obtained by imposing small levies on exports of CITES-listed wildlife.  相似文献   

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