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1.
A real-time fluorescence resonance energy transfer (FRET) PCR combined with a melting curve analysis was developed for the detection of Opisthorchis viverrini in its fish intermediate host, cyprinoid fishes. Real-time FRET PCR is based on a fluorescence melting curve analysis of a hybrid between an amplicon generated from a family of repeated DNA elements, the pOV-A6 specific probe sequence (Genbank Accession No. S80278), a 162bp repeated sequence specific to O. viverrini, and specific fluorophore-labeled probes. The real-time FRET PCR could detect as little as a single metacercaria artificially inoculated in 30 fish samples. The O. viverrini infected fishes were distinguished from non-infected fishes and from the genomic DNA of other parasites by their melting temperature. Sensitivity and specificity of this method were both 100% in the laboratory setting and it outperformed the microscopic method on field-collected samples as well. Melting curve analysis is a rapid, accurate, and sensitive alternative for the specific detection of O. viverrini infected fishes. It allows a high throughput and can be performed on small samples. The assay has not only great potential for epidemiological surveys of fish intermediate hosts but it could also be adapted as screening tool for a range of foodborne parasites in freshwater fishes.  相似文献   

2.
Background and methodologyBrucellosis in livestock causes huge economic loses of developing countries and demonstrates a serious health risks to the patrons of infected dairy goods and meat. Prevention of brucellosis in cattle relies on the trustworthiness of the techniques utilized to detect the causative pathogen. In the current investigation, we described the exploration of the well-known real-time PCR technique based on the Brucella-specific IS711 with different tissue samples of dromedary camels in Qatar.ResultsThe findings of the real-time PCR unveiled the occurrence of Brucella spp in 60 % of lung tissues, 71.42 % of liver tissues, 72 % of spleen tissues, 25 % of kidney tissues, and 42.42 % of placental fluid samples. Among them, the liver tissues and spleen tissues possessed the highest number of positive results, whereas kidney tissues displayed the lowest number of positive results for Brucella spp.ConclusionThe findings of this investigation discloses that PCR technique is a sensitive and specific technique for the identification of Brucella spp. in dromedary camels. Most of the tissues samples showed the presence of Brucella spp. and also we concluded that there is a need for further studies to be conducted in order to identify specific species of Brucella.  相似文献   

3.
Few data exist on the parasites of ratites, especially from regions within their natural range. It is only recently that extensive studies on the parasites of ostriches (Struthio camelus) have been published, mainly from European countries where commercial farming has expanded. Two species of ratites are native in South America: the lesser rhea also known as Darwin's rhea (Rhea pennata) and the greater rhea (Rhea americana). Both species are considered near threatened by the IUCN and are included in the CITES’ Appendices I and II, respectively. Parasitological studies have conservation implications, as they allow us to assess the risk of transmission of pathogens from farmed ratites to wild populations. In this study 92 faecal samples from greater rheas and 55 faecal samples from lesser rheas from different localities in Argentine were analyzed to determine their gastrointestinal parasites. In greater rheas the protozoa (Balantidium coli-like and Entamoeba spp.) and helminths (Fasciola hepatica and Deletrocephalus spp.). The protozoa had not previously been cited as parasites of greater rheas in South America. Cysts and/or trophozoites of B. coli-like were found in 16.3% of the samples, while the prevalence of the remaining parasites was below 10%. Lesser rheas harbored the protozoa B. coli-like, Entamoeba spp. and Chilomastix spp. as well as F. hepatica and nematode eggs and larvae. B. coli-like cysts were found in 20.0% of the samples, while the prevalence of the other parasites remained below 5%. Some of them had not been cited as infecting lesser rheas yet.  相似文献   

4.
The current study examined the prevalence of intestinal parasites and genotypes of Giardia intestinalis in puppies from nine pet shops in east Japan. Fresh fecal samples from 1794 puppies (≦3 months old) were collected on one occasion. Giardia spp. was examined for specific coproantigen using ELISA kit (SNAP®Giardia, IDEXX Laboratories, Inc., USA). Other intestinal parasites were detected microscopically using the formalin-ethyl acetate sedimentation technique. Genotyping was determined for the random 29 stool samples identified as Giardia spp. positive using PCR and direct sequencing of the glutamate dehydrogenase (gdh) gene. Overall prevalence of protozoan Giardia spp. and Cystoisospora spp. revealed 23.4% and 11.3%, respectively. Prevalence of ascarids, Strongyloides spp. and hookworms were recorded 1.8%, 1.1% and 0.1%, respectively. Protozoan Giardia spp. and Cystoisospora spp., thus, represent important pathogens among pet shop puppies. All genotyped G. intestinalis isolates were belonged to assemblage C or D, identified as dog-specific genotypes. Zoonotic assemblage A and B were not demonstrated. The result suggests that the risk of zoonotic transmission of G. intestinalis from pet shops puppies to humans may be quite low in Japan.  相似文献   

5.
This study investigated the presence of zoonotic parasites and vector-borne pathogens in dogs housed in kennels and shelters from four sites of Italy. A total of 150 adoptable dogs was examined with different microscopic, serological and molecular methods.Overall 129 dogs (86%) were positive for one or more parasites and/or pathogens transmitted by ectoparasites. Forty-eight (32%) were positive for one infection, while 81 (54%) for more than one pathogen. The most common zoonotic helminths recorded were hookworms, roundworms and Capillaria aerophila, followed by mosquito-borne Dirofilaria spp. and Dipylidium caninum. One hundred and thirteen (77.9%), 6 (4.1%) and 2 (1.4%) dogs were positive for Rickettsia spp., Leishmania infantum and Anaplasma spp., respectively.The results show that dogs living in rescue facilities from the studied areas may be infected by many zoonotic internal parasites and vector-borne pathogens, and that control measures should be implemented.  相似文献   

6.
BackgroundBlastocystis is a unicellular protozoan and one of the most common parasites found in humans and many animals' intestinal tract. The present study aimed to compare the genotypes of Blastocystis infecting cattle and humans in the south of Iran.MethodsA total of 100 human stool samples and 75 cattle stool samples were microscopically examined for Blastocystis infection. DNA was extracted from thirty-eight microscopically positive samples (13 humans and 25 cattle). PCR was performed on positive samples targeting the Blastocystis-specific SSU rDNA gene. PCR products of eight humans and eleven cattle samples were sequenced and compared with available reference sequences in GenBank by BLAST queries. Genetic diversity was measured for Blastocystis subtypes in human and cattle, based on haplotype and nucleotide diversities.ResultsThe PCR detected Blastocystis in ten humans and twenty-four cattle samples. Blastocystis subtypes 1, 2, and 6 were found in humans whereas subtypes 5 and 10 were found in cattle. Subtype (ST) 2 was the most predominant subtypes in humans whereas, in cattle specimens, the ST5 was the most dominant subtype. Based on the Blastocystis sequences of SSU rDNA, 68 sites were polymorphic and 49 sites were parsimony informative, resulting in the identification of 15 haplotypes, 10 haplotypes in the cattle and 5 in humans. No haplotype was shared between cattle and human parasites.ConclusionHuman-derived Blastocystis subtypes were different from cattle subtypes in southern Iran. Nevertheless, subtype 5 in cattle can be a risk factor for human infection.  相似文献   

7.
Examination of 481 faecal samples from North Island dogs revealed that 307 (63.8%) contained coccidia. The majority of infected samples contained a single coccidian but in total 4 valid coccidian parasites of dogs were identified. Two further coccidians, accidentally “parasitic” in dogs, were tentatively identified. The identities and prevalences of the valid coccidian parasites were — Isospora canis (4.0%), Isospora ohioensis (9.2%), Hammondia heydorni (2.7%), Sarcocystis spp. (58.8%); and of the accidental coccidian “parasites” — Isospora lacazei (2.1%), Eimeria spp. (9.8%).  相似文献   

8.
Salmonella (S.) Typhimurium and S. Enteritidis are the major causative agents of food-borne illnesses worldwide. Currently, a rapid detection system using multiplex real-time polymerase chain reaction (PCR) has been applied for other food-borne pathogens such as Escherichia coli, Staphylococcus aureus and Streptococcus spp. A multiplex real-time PCR was developed for the simultaneous detection of Salmonella spp., especially S. Typhimurium and S. Enteritidis, in beef and pork. For the specific and sensitive multiplex real-time PCR, three representative primers and probes were designed based on sequence data from Genbank. Among the three DNA extraction methods (boiling, alkaline lysis, and QIAamp DNA Mini Kit), the QIAamp DNA Mini Kit was the most sensitive in this study. The optimized multiplex real-time PCR was applied to artificially inoculated beef or pork. The detection sensitivity of the multiplex real-time PCR was increased. The specificity of the multiplex real-time PCR assay, using 128 pure-cultured bacteria including 110 Salmonella isolates and 18 non-Salmonella isolates, was 100%, 100% and 99.1% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The sensitivity was 100%, 100% and 91.7% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The multiplex real-time PCR assay developed in this study could detect up to 0.54 ± 0.09 and 0.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for beef, 1.45 ± 0.21 and 1.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for pork, respectively, with all conditions optimized. Our results indicated that the multiplex real-time PCR assay developed in this study could sensitively detect Salmonella spp. and specifically differentiate S. Typhimurium from S. Enteritidis in meats.  相似文献   

9.
Abstract

Species of the genus Marteilia (Phylum Paramyxea) are protozoan parasites of marine mollusks. Marteilia spp. have been detected in mollusks from different parts of the world, but the presence of these parasites in China has not been previously reported. Therefore, a survey was conducted to look for the presence of Marteilia spp. in blue mussels Mytilus edulis and Asian green mussels Perna viridis collected along China's coasts. Histological and PCR analyses revealed that 5 of 180 M. edulis (prevalence = 2.8%) were positive for infection with a Marteilia-like organism, whereas the parasite was not detected in any of the 80 P. viridis individuals tested. Total genomic DNA was extracted from the infected tissue sections for PCR amplification. The PCR amplification with Marteilia primers SS1 and SAS1 yielded the expected 641-bp product. Sequencing results showed that the 18S ribosomal RNA gene fragment from the protozoans found in M. edulis from China was 88% similar to that of Marteilia refringens, a species that was reported from M. edulis and European flat oysters Ostrea edulis collected in France. This is the first report of a Marteilia-like organism infecting M. edulis in China.

Received May 9, 2011; accepted March 4, 2012  相似文献   

10.
SUMMARY Three years after the start of an experiment to assess the merits of thiabendazole (TBZ) treatment of trichostrongylid parasites in weaner sheep, field isolates of Ostertagia spp and Trichostrongylus spp were made from weaner sheep treated under one of three treatment schemes. Treatment frequencies were “nil”, “planned” (5 or 6/year) and “regular” (every 3 weeks). In addition an isolate was taken from a group of “tracer” sheep drenched with TBZ every 10 days. Resistance to TBZ was assessed using an in vitro egg hatch assay, pre- and post-treatment faecal egg counts and a controlled anthelmintic efficiency test. Pre- and post-treatment egg counts revealed the presence of TBZ-resistance in field isolates of mixed species. Egg hatch assays indicated a level of resistance for Ostertagia spp which was proportional to the frequency of TBZ treatment. The “planned”, “regular” and “tracer” strains of Ostertagia spp had resistance ratios for eggs of 4, 13 and 15 respectively when compared to the “nil” strain. In the anthelmintic efficiency assay treatment with 44 mg kg-1 and 88 mg kg-1 of TBZ removed 82 and 96% respectively of the total Ostertagia burden (adults and larvae) from the “nil” strain and 30 and 75% respectively from the “planned” strain. The same dose rates against the “regular” and “tracer” strains and additional rates of 132 or 176 mg kg-1 against the “tracer” strain failed to reduce the Ostertagia burden significantly. Intestinal Trichostrongylus spp from all isolates were fully susceptible to TBZ at 44 mg kg-1. Levamisole at 7.0 mg kg-1 was highly effective (99% reduction) against the “tracer” strain of Ostertagia.  相似文献   

11.
Although surveillance is limited, indigenous residents at latitudes ranging from 53 to 73°N in Canada appear to have a higher occurrence of infection with some zoonotic parasites than the general population. Conversely, they are relatively naïve to other zoonotic parasites that have previously been unable to establish at northern latitudes. For those parasites that circulate among dogs, wildlife, and people, potential risk factors in the North include limited availability of veterinary services, presence of free-roaming dog populations, and consumption of locally harvested fish and wildlife. These regions are also experiencing some of the greatest impacts of climate change in North America, including increased temperature, precipitation, and frequency and severity of extreme weather. We review the current taxonomy, genetic diversity, host and geographic distributions, epidemiology and risk factors for 3 genera of helminths (Diphyllobothrium spp., Echinococcus spp., and Toxocara sp.) in Canada's North in order to identify climate-sensitive aspects of their ecology. Free-living stages of parasitic zoonoses endemic in the Arctic (such as Diphyllobothrium dendriticum, the cervid strain of Echinococcus granulosus, and Arctic strains of Echinococcus multilocularis) will experience trade-offs between enhanced survival under wetter conditions and increased mortality under warmer conditions. Climate change might also lead to the introduction and establishment in the Arctic of parasitic zoonoses previously restricted to the sub-Arctic, such as Diphyllobothrium latum, Toxocara canis, and the prairie strain of E. multilocularis. Molecular techniques applied in broad geographic surveys are needed to address critical knowledge gaps in the geographic distribution, genetic diversity, and public health significance of zoonotic helminths already in the circumpolar North, and to determine the current barriers to range expansion of temperate-adapted parasites into the North. Dogs will continue to play important roles in the North, including that of a “bridging” host between sylvatic cycles and human communities. In a warming north, increased opportunities for business, agriculture, and tourism favor importation of dogs and their parasites into a newly suitable environment. Collaborations among veterinarians, public health personnel, and policy-makers are needed to enhance surveillance and mitigate for dog-transmitted parasitic zoonoses in a changing North.  相似文献   

12.
To compare the prevalence of intestinal parasites in shelter and hunting dogs in Catalonia, Northeastern Spain, fresh faecal samples from 81 shelter dogs and 88 hunting dogs were collected and analysed by faecal flotation. The overall prevalence of intestinal parasites was 71.6% in each population. In the shelter dog group, 67.9% of dogs were positive for intestinal protozoa and 9.8% were positive for helminths. In the hunting dog group, 20.4% of dogs were positive for intestinal protozoa and 63.6% were positive for helminths. A subset of Giardia-positive samples was evaluated by PCR; Giardia assemblages C or D were detected. These results suggest that comprehensive parasite control measures should be implemented in both shelter and hunting dogs in Catalonia.  相似文献   

13.
Objective – The aim of this review is to describe and evaluate both conventional and molecular diagnostic testing utilized in dogs and cats with acute neurologic diseases. Various types of polymerase chain reaction (PCR) are explored along with novel molecular diagnostic testing that ultimately may prove useful in the critical care setting. Data Sources – PUBMED was searched to obtain relevant references material using keywords: ‘canine OR feline meningitis AND meningoencephalitis,’‘feline infectious peritonitis,’‘canine distemper,’‘canine OR feline AND toxoplasma,’‘canine neospora,’‘canine OR feline AND rickettsia,’‘granulomatous meningoencephalitis,’‘steroid responsive meningitis arteritis,’‘necrotizing encephalitis,’‘novel neurodiagnostics,’‘canine OR feline AND CNS borrelia,’‘canine OR feline AND CNS bartonella,’‘canine OR feline AND CNS fungal,’‘nested OR multiplex OR degenerate OR consensus OR CODEHOP AND PCR.’ Research findings from the authors' laboratory and current veterinary textbooks also were utilized. Human Data Synthesis – Molecular diagnostic testing including conventional, real‐time, and consensus and degenerate PCR and microarray analysis are utilized routinely for the antemortem diagnosis of infectious meningoencephalitis (ME) in humans. Recently, PCR using consensus degenerate hybrid primers (CODEHOP) has been used to identify and characterize a number of novel human viruses. Veterinary Data Synthesis – Molecular diagnostic testing such as conventional and real‐time PCR aid in the diagnosis of several important central nervous system infectious agents including canine distemper virus, Toxoplasma gondii, Neospora caninum, rickettsial species, and others. Recently, broadly reactive consensus and degenerate PCR reactions have been applied to canine ME including assays for rickettsial organisms, Borrelia spp. and Bartonella spp., and various viral families. Conclusions – In the acute neurologic patient, there are several key infectious diseases that can be pursued by a combination of conventional and molecular diagnostic testing. It is important that the clinician understands the utility, as well as the limitations, of the various neurodiagnostic tests that are available.  相似文献   

14.
A new quantitative real-time PCR (qPCR) assay based on Taqman® technology and minor groove binding (MGB) probe was developed for the diagnosis of leishmaniosis and quantification of Leishmania infantum DNA in infected dogs. This method was based on the amplification of a 122 bp fragment of the highly conserved kDNA minicircles of L. infantum. The reaction was performed using the StepOnePlus™ system with StepOne software™. This assay was able to detect the presence of protozoan parasite DNA in amounts as low as 0.03 parasites per reaction. The standard curve designed for the quantification of parasites showed linearity over seven log DNA concentration range with a correlation coefficient >0.999 and both intra- and inter-assay variability demonstrated the high efficiency and reproducibility of the assay. The qPCR also proved to be successfully applicable to different clinical samples including blood, bone marrow, lymph node aspirates and conjunctival swabs.  相似文献   

15.
Llamas (Lama glama) are intermediate hosts of the protozoan parasite Sarcocystis spp. This parasite is described as causing economic losses in the production of llama meat in South America. The aim of this study was to estimate prevalence, identify risk factors and explore spatial patterns of Sarcocystis in llamas in an area of the Bolivian High Plateau including estimating financial losses due to carcass downgrades as a result of the presence of Sarcocystis cysts.  相似文献   

16.
A symposium on “Extermination of Cattle grubs (Hypoderma spp.)” was organized at the Seventh International Conference of the World Association for the Advancement of Veterinary Parasitology held at Thessaloniki, Greece, on 14–16 July 1975. The symposium dealt mainly with regional or national programs now operating for examination of cattle grubs in several countries, including Canada, Eire, the Federal Republic of Germany, France, Northern Ireland, Switzerland, and the U.S.S.R. Besides the papers published in this issue, papers were also presented on “Warble Fly Eradication in Eire” (Thornberry, 1975); “Changes in Immune Response to Hypoderma spp. in Cattle Treated With Fenthion” (Boulard, 1975); and “Eradication of Hypodermosis: Alternatives and Auxiliaries to Chemical Control Treatments” (J. Weintraub, unpublished data).  相似文献   

17.
Hemoplasmas were detected in two apparently healthy captive South American coatis (Nasua nasua) from southern Brazil during an investigation for vector-borne pathogens. Blood was subjected to packed cell volume (PCV) determination, a commercial real-time PCR panel for the detection of Anaplasma spp., Babesia spp., Bartonella spp., Hepatozoon spp., Leishmania spp., Mycoplasma haemofelis, ‘Candidatus Mycoplasma turicensis’, ‘Candidatus Mycoplasma haemominutum’, Neorickettsia risticii, Rickettsia rickettsii and Leptospira spp., and a pan-hemoplasma conventional PCR assay. PCV was normal, but both coatis tested positive for hemoplasmas and negative for all the remaining pathogens tested. Using different techniques for microscopy (light, confocal or SEM), structures compatible with hemoplasmas were identified. Sequencing of the 16S rRNA gene identified an organism resembling Mycoplasma haemofelis and another hemotropic Mycoplasma sp., with a sequence identity of 96.8% to a Mycoplasma sp. previously detected in capybaras.  相似文献   

18.
Cryptosporidium spp. are common intestinal protozoan parasites that infect a wide range of hosts, including humans and livestock, worldwide. The objective of this study was to determine the prevalence of Cryptosporidium spp. in dairy calves in Prince Edward Island, Canada, and the potential for transmission of this parasite between dairy calves and humans. Fecal samples were collected from 183 dairy calves from 11 farms in Prince Edward Island. The prevalence of Cryptosporidium spp. infections in these animals was determined by examining for the presence of oocysts in the fecal samples, using immunofluorescence microscopy. Molecular characterization was done using a nested-PCR protocol to amplify fragments of the Cryptosporidium heat-shock protein 70 gene, followed by DNA sequencing. Ten calves (6.2%), representing 4 out of 11 farms tested, were positive for Cryptosporidium spp. DNA sequence analysis on five PCR positive samples demonstrated that Cryptosporidium parvum was the only species present in the calves tested, suggesting that there is a potential risk of zoonotic transmission between dairy calves and humans in this region.  相似文献   

19.
BackgroundInfection with Bartonella species is common in cats but reported effects of bacteremia on laboratory variables differ.ObjectivesEvaluate for associations between Bartonella bacteremia and CBC and serum biochemical changes in sick and healthy cats throughout the United States.AnimalsA total of 3964 client‐owned cats.MethodsRetrospective cohort study using submissions to a commercial laboratory between 2011 and 2017. Serum biochemistry and CBC abnormalities (categorized as above or below reference intervals), age, and location (high‐ or low‐risk state for Ctenocephalides felis) in presumed healthy and sick cats were evaluated for associations with presence of Bartonella spp. DNA, detected by PCR. Univariate and multivariable logistic regression analyses were performed.Results Bartonella spp. DNA was amplified from 127 (3.2%) of 3964 cats; 126 (99.2%) of 127 were from high flea risk states and 121 (95.3%) of 127 were presumed sick. Fever of unknown origin was the most common PCR panel requested. In the multivariable analysis, neutrophilia, decreased ALP activity, clinical status (presumed sick), and young age (≤2 years) each were positively associated whereas neutropenia and hyperproteinemia both were negatively associated with Bartonella spp. bacteremia. Presence of Bartonella spp. DNA had no association with test results for other infectious disease agents.Conclusions and Clinical ImportanceIn both healthy and sick cats, active Bartonella infections had minimal association with clinically relevant laboratory abnormalities. However, based on these results, in areas considered high risk for C. felis, active infection with Bartonella spp. is a reasonable differential diagnosis for cats presented with unexplained fever and neutrophilia, particularly if the cat is young.  相似文献   

20.
BackgroundBlastocystis, a common intestinal protozoan of humans and animals, infected more than 1 billion people around the world. This enteric protozoan is frequently reported in both healthy individuals and patients with gastrointestinal (GI) symptoms.MethodsThree hundred and forty-five fecal samples including 151 GI patients and 194 healthy individuals were examined by microscopy, culture and PCR-sequencing techniques to determine Blastocystis frequency and subtype (ST) variation.ResultsThe occurrence of Blastocystis was detected 56 (16.2%) and 85 (24.6%) by microscopy, culture and PCR methods, respectively. Out of the 85 positive patients, 60 (70.6%) were asymptomatic and 25 (29.4%) were symptomatic. The results of 41 successfully sequenced isolates identified 8 (19.5%), 8 (19.5%), and 25 (61.0%) ST1, ST2, and ST3, respectively.ConclusionThis study has found that Blastocystis was more common in healthy individuals than GI patients. Another finding was that no correlation was found between clinical symptoms and Blastocystis STs.  相似文献   

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