[Objective]To predict prevalence of fleas via a simple epidemiological model.[Method]The field investigation was carried out in 23 locations in Yunnan Province.A simple epidemiological model was involved mean abundanc...[Objective]To predict prevalence of fleas via a simple epidemiological model.[Method]The field investigation was carried out in 23 locations in Yunnan Province.A simple epidemiological model was involved mean abundance and variance of abundance.[Result]The prevalence of fleas increased with their mean abundance in logistic curve.A linear correlation of the predicted prevalence against observed prevalence did not differ significantly from unity.[Conclusion]Prevalence could be explained simply by their mean abundance.展开更多
Among the sundry studies in China on John Donne's The Flea,there has been none done from the perspective of Reader-Oriented Theory to probe into the readers' roles in the construction of meaning.The present ar...Among the sundry studies in China on John Donne's The Flea,there has been none done from the perspective of Reader-Oriented Theory to probe into the readers' roles in the construction of meaning.The present article under Wolfgang Iser's theories,in a further pursuit of the expansion of the gestalt of such studies on the poem,aims at exploring the readers' active roles in complementing,completing and recreating the textual meaning,and differentiating the implied reader and the actual reader through the poem as well as attempting to fulfill the construction of the reading cognitive model through the interpretation of the conceit the flea.展开更多
The authors report a case of human dermal complications by Ctenocephalides fills felis(cat flea)in a 28 years old woman who dwell in rural area in Mazandaran province,Iran.Furthermore,in the current report clinical ma...The authors report a case of human dermal complications by Ctenocephalides fills felis(cat flea)in a 28 years old woman who dwell in rural area in Mazandaran province,Iran.Furthermore,in the current report clinical manifestations,etiology and different aspects of infestation were discussed elaborately.And the importance of controlling fleas was highlighted as well.展开更多
Biotic stresses negatively affect canola growth and production. Flea beetle damage and Sclerotinia sclerotiorum (S. sclerotiorum) infection are two of the worst biotic stresses for canola. Auxin Repressed Proteins (AR...Biotic stresses negatively affect canola growth and production. Flea beetle damage and Sclerotinia sclerotiorum (S. sclerotiorum) infection are two of the worst biotic stresses for canola. Auxin Repressed Proteins (ARPs) responsive to several abiotic stresses have been reported. However, information about ARPs induced by Flea beetle damage and S. sclerotiorum infection, their roles in biotic stress tolerance are still lacking in canola. ESTs for an Auxin Repressed Protein 1 (BnARP1) were highly represented (expressed) in a Brassica napus subtractive library developed after leaf damage by the crucifer flea beetle (Phyllotreta cruciferae). Expression of this gene was under different developmental control in B. napus, and it was co-induced in B. napus by flea beetle feeding, S. sclerotiorum infection, drought and cold. A total of 25 BnARP genes were represented in different B. napus stress and development EST libraries and indicated larger, diversified families than known earlier. Dwarf phenotypes, primary root growth inhibition, lateral root enhancement, reduced sensitivity to 2, 4-D, and reduced PIN1 and LOX expression in transgenic Arabidopsis expression lines suggest that BnARP1 is an auxin repressor that prevents auxin transport and supports an interaction between the auxin and jasmonate signalling pathways. And the increased survival after S. sclerotiorum infection in transgenic over-expression Arabidopsis suggests that BnARP1 could play a role in S. sclerotiorum tolerance through connecting auxin and jasmonate signalling pathways.展开更多
The aim of the present study was to evaluate the efficacy of two commercial pour-on ivermectin formulations against intestinal parasites (IP), fleas and lice in naturally infested stray dogs. Eighteen crossbreed dogs ...The aim of the present study was to evaluate the efficacy of two commercial pour-on ivermectin formulations against intestinal parasites (IP), fleas and lice in naturally infested stray dogs. Eighteen crossbreed dogs with eggs of IP as well as adult fleas and lice were included in the trial. On day 0, the dogs were randomly divided into 3 groups of 6 animals each: a group receiving a single pour-on treatment with 0.5% ivermectin (500 mcg/kg), a group treated similarly with 0.2% iver-mectin (200 mg/kg), and a control group. Fecal and skin analyses were carried out on days 0, 7, 14, 21 and 28 to determine the reduction of eggs and the number of fleas and lice. Weight gain was also measured on day 28. On day 30, the dogs were humanely sacrificed in order to count adult IP. Efficacy was measured as the percentage of the reduction of eggs per gram fecal mass (EPGF), of adult IP, fleas and lice relative to the control group. For the eggs of IP, ivermectin at 0.5% showed an efficacy of 100% against ascarids and 79% against Ancylostoma caninum. ivermectin at 0.2% removed 90.2% of the ascarids and 50.4% of A. caninum. For adult IP, the efficacy of 0.5% iver-mectin against Toxocara canis and A. caninum was 100%, and for 0.2% ivermectin it was 62.4% and 76.4% for T. canis and A. caninum, respectively. Both compounds were 100% effective against lice and 96% and 71.1% efficacious against fleas, respectively. However, neither treatment was effective against Dypilidium caninum. Weight gain in treated dogs was statistically different from that of the controls (p < 0.05). We concluded that 0.5% pour-on ivermectin showed better efficacy than 0.2% pour-on ivermectin in the reduction of eggs and adult intestinal parasites and fleas;it was similarly efficacious against lice.展开更多
受爵士音乐和朋克摇滚影响的天才型贝司手Flea（Michael Balzary）,作为美国摇滚乐队Red Hot Chili Peppers（红辣椒乐队）不可或缺的灵魂人物之一,他那出色的演奏风格促使红辣椒乐队走向摇滚巅峰而且重新赋予了贝司手在现代的定义。
...受爵士音乐和朋克摇滚影响的天才型贝司手Flea（Michael Balzary）,作为美国摇滚乐队Red Hot Chili Peppers（红辣椒乐队）不可或缺的灵魂人物之一,他那出色的演奏风格促使红辣椒乐队走向摇滚巅峰而且重新赋予了贝司手在现代的定义。
在过去的四十年里,Flea以其独特的演奏方式为摇滚音乐带来耳目一新的景象,并激发无数贝司手在开拓新技巧时要在音色上恰当融入时髦元素。展开更多
John Donne is a representative of 17th century English metaphysical poets.Donne's poetry embraces a wide range of secular and religious subjects.His poetry is full of philosophical metaphor,and quick thinking acti...John Donne is a representative of 17th century English metaphysical poets.Donne's poetry embraces a wide range of secular and religious subjects.His poetry is full of philosophical metaphor,and quick thinking activities are lively and strong passions-love passion and the passion of religious integration,which created a new harmony.Reading Donne's poetry is like participating in a mental game,only use our brains in order to catch up with speeding on the poet's imagination,his exquisite taste of the speculation.The Flea is one of representative works by John Donne.A Valediction: Forbidding Mourning is the most famous works of Donne's works.Both "The Flea" and "A Valediction: Forbidding Mourning" are famous love poems by John Donne.The two poems have something in common and something different.Although the two poems are similar and also different to each other,they both set their own situation properly and impressively.展开更多
Fleas that infest pets are considered important parasites of both animals and humans. These insects cause irritation and can also transmit zoonotic diseases. Research has led to a rapid expansion in the development of...Fleas that infest pets are considered important parasites of both animals and humans. These insects cause irritation and can also transmit zoonotic diseases. Research has led to a rapid expansion in the development of flea control products. In the face of a market that offers dozens of commercial ectoparasiticides for dogs and cats, pet owners and veterinarians must be provided with evidence to support their decision to select a product to control fleas. To compare the efficacy of three commercially available products against companion animal fleas, a trial was conducted on naturally-infested dogs in order to validate their pulicidal activity. Thirty-two flea-infested dogs with fleas were divided into 4 groups (n = 8) for each treatment. Group 1 received one pipette of permethrin as a spot-on dose of 650 mg/ml. The second group received 9.7% fipronil as a spot-on formulation. Group 3 was treated with a spot-on formulation of permethrin 7.40% plus piperonyl butoxide at 7.40%. Group 4 remained as the untreated control. Fleas of all experimental dogs were examined and counted on days 0, 3, 7, 14, 21 and 28 to determine the percentage of flea reduction. Results showed a 100% efficacy for all tested products. Identified species were: Ctenocephalides felis (75.7%), Ctenocephalides canis (15.9%) and Pulex irritans (9.5%). Based on these results, it was concluded that the three anti-flea products evaluated under the conditions of this study, produced an excellent efficacy as from the third day after treatment.展开更多
Objective:Fleas are vectors for the transmission of various pathogens.The study is to understand the pathogens carried by parasitic fleas in domestic dogs and to evaluate the pathogenic potential risk to humans.Method...Objective:Fleas are vectors for the transmission of various pathogens.The study is to understand the pathogens carried by parasitic fleas in domestic dogs and to evaluate the pathogenic potential risk to humans.Methods:121 fleas were collected from 6 dogs in different farmers’households in Suichuan County,Ji’an City,Jiangxi Province in July 2023.Flea species were determined through morphological identification and CoII gene detection.Whole genomic DNA was extracted from all 121 fleas,and six pathogens-Borrelia burgdorferi,Borrelia miyamotoi,Anaplasma phagocytophilum,Coxiella burnetii,spotted fever group Rickettsia,and Ehrlichia chaffiensis—were detected using nested polymerase chain reaction(PCR).Results:Positive products were sequenced,and the carrier status of each pathogen was analyzed.Of the 121 fleas identified,118 were Pulex irritans and 3 were Ctenocephalides felis.PCR results revealed that Borrelia burgdorferi(5%,6/118),Borrelia miyamotoi(0.8%,1/118),Borrelia hermsii(9%,11/118),Anaplasma phagocytophilum(0.8%,1/118),spotted fever group Rickettsia(0.8%,1/118),and Coxiella burnetii(0.8%,1/118)were detected in Pulex irritans.Additionally,one sample showed mixed infection with both Borrelia burgdorferi and Anaplasma phagocytophilum(0.8%,1/118).Conclusions:This study suggests that Pulex irritans can carry multiple pathogens,with implications for public health needs that warrant further investigation.展开更多
We inferred the patterns of co-occurrence of flea species in compound(across all host species)and component(across conspecific hosts)communities from six regions of the world(Mongolia,Northwest Argentina,Argentinian P...We inferred the patterns of co-occurrence of flea species in compound(across all host species)and component(across conspecific hosts)communities from six regions of the world(Mongolia,Northwest Argentina,Argentinian Patagonia,West Siberia,Slovakia,and South Africa)using the novel eigenvector ellipsoid method.This method allows us to infer structural community patterns by comparing species’environmental requirements with the pattern of their co-occurrences.We asked whether:(a)communities are characterized by species segregation,nestedness,or modularity;(b)patterns detected by the novel method conform to the patterns identified by traditional methods that search for non-randomness in community structure;and(c)the pattern of flea species co-occurrences in component communities is associated with host species traits.The results of the application of the eigenvector ellipsoid method suggested that the co-occurrence of flea species was random in all compound communities except in South Africa,where this community demonstrated a tendency to be nested.Flea species co-occurrences were random in many component communities.Species segregation was detected in the flea community of one host,whereas the flea communities of 14 hosts from different regions appeared to be nested.No indication of a modular structure in any community was found.The nestedness of flea component communities was mainly characteristic of hosts with a low relative brain mass.We concluded that the application of this novel method that combines data on species distribution and their environmental requirements allows better identification of the community structural patterns and produces more reliable results as compared with traditional methods.展开更多
The mating behavior of cat flea, Ctenocephalides felis (Bouche) was studied on an artificial feeding device. Male and female can mate repeatedly with same partner or different ones. In the situation of male: femal...The mating behavior of cat flea, Ctenocephalides felis (Bouche) was studied on an artificial feeding device. Male and female can mate repeatedly with same partner or different ones. In the situation of male: female ratio of 1:5, each mating lasted an average of 6.6 min, with a mean interval between matings at 2.5 min., compared to 11.1 min and 12.1 min respectively in a cell with 5 males and 1 female. As many as 48 mating events were observed for one male during an 8 h period. One female mated 27 times in 7 h with 5 males in the same cell. Newly emerged males and females can not mate before blood meal and about 24 h blood feeding is required for successful mating. Newly emerged males can not mate with fed females (fed for 48 h), but fed males can mate with newly emerged females who are feeding the blood. Significantly more male contacts and male male mating attempts were observed after the paper treated with female extract was introduced into the cell. The paper contacts and mating attempts were 16.75-32.25 times and 15.75-31.38 times, respectively, on average during a period of 20 min when different doses (FE) of extract were provided.展开更多
Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the...Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the spillover of ectoparasites becausefleas and ticks may gather on surviving rodents.Therefore,it is necessary to killfleas and ticks before culling rodents to minimize the risk of pathogen transmission.In this study,we used a mixture of ivermectin(an antiparasitic drug)and bromadiolone(an anticoagulant rodenticide)to control both rodent andflea/tick abundances.We found that in a laboratory test,0.01%ivermectin bait was not lethal for greater long-tailed hamsters after 7 days of treatment,while 0.1%ivermectin bait was lethal for approximately 33%of treated rodents.In afield test,bait containing 0.001%,0.005%,0.01%,and 0.05%ivermectin decreased the number offleas per vole of Brandt’s voles to 0.42,0.22,0.12,and 0.2,respectively,compared with 0.77 in the control group,indicating that 0.01%ivermectin bait performed best in removingfleas.In another laboratory test,bait containing a 0.01%ivermectin and 0.005%bromadiolone mixture caused the death of all voles within 6–14 days after the intake of the bait.In thefield test,the bait containing 0.01%ivermectin and 0.005%bromadiolone reduced the average number offleas per vole to 0.35,which was significantly lower than the 0.77 of the control group.Our results indicate that a 0.01%ivermectin and 0.005%bromadiolone mixture could be used to control both rodents andfleas to minimize the spillover risk of disease transmission when using traditional rodenticides.展开更多
Plague,caused by the Yersinia pestis bacterium,has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Cearáto the Southeastern State ofMinas Ger...Plague,caused by the Yersinia pestis bacterium,has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Cearáto the Southeastern State ofMinas Gerais and another separated area at the State of Rio de Janeiro.This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019.Furthermore,we discuss how the interaction between Y.pestis and some rodent host species may play a role in the disease dynamics.The absence of human cases nowadays in Brazil does not mean that it was eradicated.The dynamics of plague in Brazil and in other countries where it was introduced during the 3rd pandemic are quite alike,alternating epidemics with decades of quiescence.Hence,it remains an important epidemic disease of global concern.The existence of a large animal reservoir and competent vectors demonstrate a need for continuous surveillance to prevent new outbreaks of this disease in humans.展开更多
We investigated host and flea species composition across different habitats during dry and rainy seasons in the Western Usambara Mountains in Tanzania.During both seasons,similarity in flea species composition increas...We investigated host and flea species composition across different habitats during dry and rainy seasons in the Western Usambara Mountains in Tanzania.During both seasons,similarity in flea species composition increased with an increase in the similarity in host species composition.Nevertheless,between-season within-habitat as well as within-season between-habitat similarity in host species composition was higher than similarity in flea species composition.Ordination of habitats according to their host and flea species composition demonstrated that the pattern of between-habitat similarity in both host and flea species composition varied seasonally.Despite the relatively rich mammal and flea fauna of the study region,the major contribution to variation in species composition between seasons and among habitats was due to a few species only.Flea assemblages on Lophuromys kilonzoi Verheyen et al.,2007 and Praomys delectorum Thomas,1910 in different habitats were equally similar in either season.In contrast,flea assemblages on Mastomys natalensis(Smith,1834)occurring in different habitats were more similar in the dry than in the rainy season,whereas the opposite was the case for fleas on Grammomys sp.In different hosts,the main differences in species composition of flea assemblages between seasons as well as among habitats were due to different flea species.Although our results support the earlier idea that parasite species composition is determined by both host species composition and habitat properties,the former appears to explain variance in flea species composition between localities in the tropics better than between localities in temperate and arid zones.展开更多
Climatic factors are closely associated with the occurrence of vector‐borne diseases,and they also influence the distribution of vectors.The occurrence of plague is closely related to the population dynamics of fleas...Climatic factors are closely associated with the occurrence of vector‐borne diseases,and they also influence the distribution of vectors.The occurrence of plague is closely related to the population dynamics of fleas and their host animals,as well as climatic conditions.This study focused on Xilingol League,utilizing climatic and flea index data from 2012 to 2021.Spearman correlation and"Boruta"importance analysis were conducted to screen for climatic variables.A generalized additive model(GAM)was employed to investigate the influence of climatic factors and rodent density on the flea index.GAM analysis revealed distinct trends in flea index among different rodent hosts.For Meriones unguiculatus,the flea index declined with increased density and with higher humidity,yet rose with greater lagged sunshine duration.For Spermophilus dauricus,an initial increase in flea index with density was observed,followed by a decrease,and a rise in the index was noted when ground temperatures were low.This study reveals the nonlinear interactions and lag effects among climatic factors,density,and flea index.Climatic factors and density variably influence the flea index of two Yersinia pestis hosts.This research advances the prediction and early warning efforts for plague control,providing a theoretical basis for rodent and flea eradication strategies.展开更多
We tested for the effects of latitude and geographic range size(GRS)on body size,leg length,and sexual size dimorphism(SSD)across 103 species offleas,taking into account phylogenetic between-species relationships.When ...We tested for the effects of latitude and geographic range size(GRS)on body size,leg length,and sexual size dimorphism(SSD)across 103 species offleas,taking into account phylogenetic between-species relationships.When the data on body size were combined for males and females,the positive correlation between body size and latitude,but not GRS,was revealed.When the analysis was restricted to one sex only,the effect of latitude appeared to be non-significant for females,whereas male body size increased with an increase in latitude.Intraspecific body size variation was not associated with either the latitude or the latitudinal span of the geographic range,independently of which data subset was analyzed.No evidence of association between size-independent tibia length and latitude was found for either females,males,or both sexes combined.The degree of SSD decreased with a decrease in latitude but was not affected by GRS.We conclude that macroecological patterns might be manifested differently in males and females.This should be kept in mind while searching for these patterns.展开更多
We studied spatial variation in the effects of environment and network size on species positions and roles in multiple flea–mammal networks from four biogeographic realms.We asked whether species positions(measured a...We studied spatial variation in the effects of environment and network size on species positions and roles in multiple flea–mammal networks from four biogeographic realms.We asked whether species positions(measured as species strength[SS],the degree of interaction specialization[d],and the eigenvector centrality[C])or the roles of fleas and their hosts in the interaction networks:(a)are repeatable/conserved within a flea or a host species;(b)vary in dependence on environmental variables and/or network size;and(c)the effects of environment and network size on species positions or roles in the networks depend on species traits.The repeatability analysis of species position indices for 441 flea and 429 host species,occurring in at least two networks,demonstrated that the repeatability of SS,d,and C within a species was significant,although not especially high,suggesting that the indices’values were affected by local factors.The majority of flea and host species in the majority of networks demonstrated a peripheral role.A value of at least one index of species position was significantly affected by environmental variables or network size in 41 and 36,respectively,of the 52 flea and 52 host species that occurred in multiple networks.In both fleas and hosts,the occurrence of the significant effect of environment or network size on at least one index of species position,but not on a species’role in a network,was associated with some species traits.展开更多
Background:This scoping review provides a baseline summary of the current records of the ticks,fleas,and mites of public health importance that are present in Bangladesh.It summarizes their geographic distributions an...Background:This scoping review provides a baseline summary of the current records of the ticks,fleas,and mites of public health importance that are present in Bangladesh.It summarizes their geographic distributions and reports the levels of their infestation of livestock,pets,wildlife,and humans,and the clinical and epidemiological studies pertinent to these vectors and their pathogens.Methods:Sixty-one articles were identified in a literature search,including 43 published since 2011.Results:Twelve articles contained reliable information on ticks and their associated hosts.However,informa-tion on fleas and mites in Bangladesh is very limited.Seventeen species of ixodid ticks that commonly parasitize peridomestic animals and can bite humans are described:Rhipicephalus microplus,R.appendiculatus,R.sanguineus,Haemaphysalis bispinosa,Hyalomma anatolicum,and Amblyomma testudinarium.Thirty-eight veterinary articles de-scribe livestock pathogens,including Babesia,Anaplasma,and Theileria,and the diseases they cause.Few of those studies used modern molecular techniques to identify these pathogens.Eleven articles reported human diseases or surveillance studies,10 from the last 10 years.Two country-wide serosurveys of 1,209 and 720 patients,us-ing Enzyme Linked Immunosorbent Assay(ELISA)and Indirect Immunofluorescence Assay(IFA),respectively,reported human exposure to Orientia tsutsugamushi(8.8%–23.7%),typhus and spotted-fever group rickettsiae(19.7%–66.6%),and Coxiella burnetii(3%).The seropositivity rates varied regionally.PCR-based studies con-firmed that febrile patients in Bangladesh may be infected with O.tsutsugamushi,Rickettsia typhi,Rickettsia felis,or Bartonella elizabethae.Only limited molecular research has been done with dogs and cats.These studies have reported PCR-confirmed canine infections with Babesia gibsoni(30%),Anaplasma bovis(58%),or Rickettsia monace-nis(14%,n=50),and feline infections with Rickettsia felis(21%,n=100).Similarly,fleas from cats tested positive for Rickettsia felis(20.6%).Conclusions:These findings indicate that diseases borne by non-mosquito vectors in Bangladesh urgently require more attention from public health,medical,and veterinary specialists to establish their true occurrence.展开更多
基金Supported by Yunnan Provincial Foundation for Key Scientific Projects (2007C0005Z2)~~
文摘[Objective]To predict prevalence of fleas via a simple epidemiological model.[Method]The field investigation was carried out in 23 locations in Yunnan Province.A simple epidemiological model was involved mean abundance and variance of abundance.[Result]The prevalence of fleas increased with their mean abundance in logistic curve.A linear correlation of the predicted prevalence against observed prevalence did not differ significantly from unity.[Conclusion]Prevalence could be explained simply by their mean abundance.
文摘Among the sundry studies in China on John Donne's The Flea,there has been none done from the perspective of Reader-Oriented Theory to probe into the readers' roles in the construction of meaning.The present article under Wolfgang Iser's theories,in a further pursuit of the expansion of the gestalt of such studies on the poem,aims at exploring the readers' active roles in complementing,completing and recreating the textual meaning,and differentiating the implied reader and the actual reader through the poem as well as attempting to fulfill the construction of the reading cognitive model through the interpretation of the conceit the flea.
基金Supported by the Young Researchers Club,Islamic Azad University,Babol Branch,Iran(Grant NO.:BPJ1392)
文摘The authors report a case of human dermal complications by Ctenocephalides fills felis(cat flea)in a 28 years old woman who dwell in rural area in Mazandaran province,Iran.Furthermore,in the current report clinical manifestations,etiology and different aspects of infestation were discussed elaborately.And the importance of controlling fleas was highlighted as well.
文摘Biotic stresses negatively affect canola growth and production. Flea beetle damage and Sclerotinia sclerotiorum (S. sclerotiorum) infection are two of the worst biotic stresses for canola. Auxin Repressed Proteins (ARPs) responsive to several abiotic stresses have been reported. However, information about ARPs induced by Flea beetle damage and S. sclerotiorum infection, their roles in biotic stress tolerance are still lacking in canola. ESTs for an Auxin Repressed Protein 1 (BnARP1) were highly represented (expressed) in a Brassica napus subtractive library developed after leaf damage by the crucifer flea beetle (Phyllotreta cruciferae). Expression of this gene was under different developmental control in B. napus, and it was co-induced in B. napus by flea beetle feeding, S. sclerotiorum infection, drought and cold. A total of 25 BnARP genes were represented in different B. napus stress and development EST libraries and indicated larger, diversified families than known earlier. Dwarf phenotypes, primary root growth inhibition, lateral root enhancement, reduced sensitivity to 2, 4-D, and reduced PIN1 and LOX expression in transgenic Arabidopsis expression lines suggest that BnARP1 is an auxin repressor that prevents auxin transport and supports an interaction between the auxin and jasmonate signalling pathways. And the increased survival after S. sclerotiorum infection in transgenic over-expression Arabidopsis suggests that BnARP1 could play a role in S. sclerotiorum tolerance through connecting auxin and jasmonate signalling pathways.
文摘The aim of the present study was to evaluate the efficacy of two commercial pour-on ivermectin formulations against intestinal parasites (IP), fleas and lice in naturally infested stray dogs. Eighteen crossbreed dogs with eggs of IP as well as adult fleas and lice were included in the trial. On day 0, the dogs were randomly divided into 3 groups of 6 animals each: a group receiving a single pour-on treatment with 0.5% ivermectin (500 mcg/kg), a group treated similarly with 0.2% iver-mectin (200 mg/kg), and a control group. Fecal and skin analyses were carried out on days 0, 7, 14, 21 and 28 to determine the reduction of eggs and the number of fleas and lice. Weight gain was also measured on day 28. On day 30, the dogs were humanely sacrificed in order to count adult IP. Efficacy was measured as the percentage of the reduction of eggs per gram fecal mass (EPGF), of adult IP, fleas and lice relative to the control group. For the eggs of IP, ivermectin at 0.5% showed an efficacy of 100% against ascarids and 79% against Ancylostoma caninum. ivermectin at 0.2% removed 90.2% of the ascarids and 50.4% of A. caninum. For adult IP, the efficacy of 0.5% iver-mectin against Toxocara canis and A. caninum was 100%, and for 0.2% ivermectin it was 62.4% and 76.4% for T. canis and A. caninum, respectively. Both compounds were 100% effective against lice and 96% and 71.1% efficacious against fleas, respectively. However, neither treatment was effective against Dypilidium caninum. Weight gain in treated dogs was statistically different from that of the controls (p < 0.05). We concluded that 0.5% pour-on ivermectin showed better efficacy than 0.2% pour-on ivermectin in the reduction of eggs and adult intestinal parasites and fleas;it was similarly efficacious against lice.
文摘受爵士音乐和朋克摇滚影响的天才型贝司手Flea（Michael Balzary）,作为美国摇滚乐队Red Hot Chili Peppers（红辣椒乐队）不可或缺的灵魂人物之一,他那出色的演奏风格促使红辣椒乐队走向摇滚巅峰而且重新赋予了贝司手在现代的定义。
在过去的四十年里,Flea以其独特的演奏方式为摇滚音乐带来耳目一新的景象,并激发无数贝司手在开拓新技巧时要在音色上恰当融入时髦元素。
文摘John Donne is a representative of 17th century English metaphysical poets.Donne's poetry embraces a wide range of secular and religious subjects.His poetry is full of philosophical metaphor,and quick thinking activities are lively and strong passions-love passion and the passion of religious integration,which created a new harmony.Reading Donne's poetry is like participating in a mental game,only use our brains in order to catch up with speeding on the poet's imagination,his exquisite taste of the speculation.The Flea is one of representative works by John Donne.A Valediction: Forbidding Mourning is the most famous works of Donne's works.Both "The Flea" and "A Valediction: Forbidding Mourning" are famous love poems by John Donne.The two poems have something in common and something different.Although the two poems are similar and also different to each other,they both set their own situation properly and impressively.
文摘Fleas that infest pets are considered important parasites of both animals and humans. These insects cause irritation and can also transmit zoonotic diseases. Research has led to a rapid expansion in the development of flea control products. In the face of a market that offers dozens of commercial ectoparasiticides for dogs and cats, pet owners and veterinarians must be provided with evidence to support their decision to select a product to control fleas. To compare the efficacy of three commercially available products against companion animal fleas, a trial was conducted on naturally-infested dogs in order to validate their pulicidal activity. Thirty-two flea-infested dogs with fleas were divided into 4 groups (n = 8) for each treatment. Group 1 received one pipette of permethrin as a spot-on dose of 650 mg/ml. The second group received 9.7% fipronil as a spot-on formulation. Group 3 was treated with a spot-on formulation of permethrin 7.40% plus piperonyl butoxide at 7.40%. Group 4 remained as the untreated control. Fleas of all experimental dogs were examined and counted on days 0, 3, 7, 14, 21 and 28 to determine the percentage of flea reduction. Results showed a 100% efficacy for all tested products. Identified species were: Ctenocephalides felis (75.7%), Ctenocephalides canis (15.9%) and Pulex irritans (9.5%). Based on these results, it was concluded that the three anti-flea products evaluated under the conditions of this study, produced an excellent efficacy as from the third day after treatment.
基金Supported by the National Major Science and Technology Project of China(2017ZX10303404006003)the Independent Research Project of the National Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention(32055).
文摘Objective:Fleas are vectors for the transmission of various pathogens.The study is to understand the pathogens carried by parasitic fleas in domestic dogs and to evaluate the pathogenic potential risk to humans.Methods:121 fleas were collected from 6 dogs in different farmers’households in Suichuan County,Ji’an City,Jiangxi Province in July 2023.Flea species were determined through morphological identification and CoII gene detection.Whole genomic DNA was extracted from all 121 fleas,and six pathogens-Borrelia burgdorferi,Borrelia miyamotoi,Anaplasma phagocytophilum,Coxiella burnetii,spotted fever group Rickettsia,and Ehrlichia chaffiensis—were detected using nested polymerase chain reaction(PCR).Results:Positive products were sequenced,and the carrier status of each pathogen was analyzed.Of the 121 fleas identified,118 were Pulex irritans and 3 were Ctenocephalides felis.PCR results revealed that Borrelia burgdorferi(5%,6/118),Borrelia miyamotoi(0.8%,1/118),Borrelia hermsii(9%,11/118),Anaplasma phagocytophilum(0.8%,1/118),spotted fever group Rickettsia(0.8%,1/118),and Coxiella burnetii(0.8%,1/118)were detected in Pulex irritans.Additionally,one sample showed mixed infection with both Borrelia burgdorferi and Anaplasma phagocytophilum(0.8%,1/118).Conclusions:This study suggests that Pulex irritans can carry multiple pathogens,with implications for public health needs that warrant further investigation.
基金supported by the Israel Science Foundation(grant no.548/23 to B.R.K.and I.S.K.).
文摘We inferred the patterns of co-occurrence of flea species in compound(across all host species)and component(across conspecific hosts)communities from six regions of the world(Mongolia,Northwest Argentina,Argentinian Patagonia,West Siberia,Slovakia,and South Africa)using the novel eigenvector ellipsoid method.This method allows us to infer structural community patterns by comparing species’environmental requirements with the pattern of their co-occurrences.We asked whether:(a)communities are characterized by species segregation,nestedness,or modularity;(b)patterns detected by the novel method conform to the patterns identified by traditional methods that search for non-randomness in community structure;and(c)the pattern of flea species co-occurrences in component communities is associated with host species traits.The results of the application of the eigenvector ellipsoid method suggested that the co-occurrence of flea species was random in all compound communities except in South Africa,where this community demonstrated a tendency to be nested.Flea species co-occurrences were random in many component communities.Species segregation was detected in the flea community of one host,whereas the flea communities of 14 hosts from different regions appeared to be nested.No indication of a modular structure in any community was found.The nestedness of flea component communities was mainly characteristic of hosts with a low relative brain mass.We concluded that the application of this novel method that combines data on species distribution and their environmental requirements allows better identification of the community structural patterns and produces more reliable results as compared with traditional methods.
文摘The mating behavior of cat flea, Ctenocephalides felis (Bouche) was studied on an artificial feeding device. Male and female can mate repeatedly with same partner or different ones. In the situation of male: female ratio of 1:5, each mating lasted an average of 6.6 min, with a mean interval between matings at 2.5 min., compared to 11.1 min and 12.1 min respectively in a cell with 5 males and 1 female. As many as 48 mating events were observed for one male during an 8 h period. One female mated 27 times in 7 h with 5 males in the same cell. Newly emerged males and females can not mate before blood meal and about 24 h blood feeding is required for successful mating. Newly emerged males can not mate with fed females (fed for 48 h), but fed males can mate with newly emerged females who are feeding the blood. Significantly more male contacts and male male mating attempts were observed after the paper treated with female extract was introduced into the cell. The paper contacts and mating attempts were 16.75-32.25 times and 15.75-31.38 times, respectively, on average during a period of 20 min when different doses (FE) of extract were provided.
基金We are grateful to the grant supported by Science and Technology Service Network Initiative of the Chinese Academy of Sciences(KFJ-STS-ZDTP-2021-002).
文摘Rodent pests not only cause severe agricultural loss but also spread zoonotic pathogens to human beings.Antico-agulant rodenticides are widely used to decrease the population densities of rodents but often lead to the spillover of ectoparasites becausefleas and ticks may gather on surviving rodents.Therefore,it is necessary to killfleas and ticks before culling rodents to minimize the risk of pathogen transmission.In this study,we used a mixture of ivermectin(an antiparasitic drug)and bromadiolone(an anticoagulant rodenticide)to control both rodent andflea/tick abundances.We found that in a laboratory test,0.01%ivermectin bait was not lethal for greater long-tailed hamsters after 7 days of treatment,while 0.1%ivermectin bait was lethal for approximately 33%of treated rodents.In afield test,bait containing 0.001%,0.005%,0.01%,and 0.05%ivermectin decreased the number offleas per vole of Brandt’s voles to 0.42,0.22,0.12,and 0.2,respectively,compared with 0.77 in the control group,indicating that 0.01%ivermectin bait performed best in removingfleas.In another laboratory test,bait containing a 0.01%ivermectin and 0.005%bromadiolone mixture caused the death of all voles within 6–14 days after the intake of the bait.In thefield test,the bait containing 0.01%ivermectin and 0.005%bromadiolone reduced the average number offleas per vole to 0.35,which was significantly lower than the 0.77 of the control group.Our results indicate that a 0.01%ivermectin and 0.005%bromadiolone mixture could be used to control both rodents andfleas to minimize the spillover risk of disease transmission when using traditional rodenticides.
文摘Plague,caused by the Yersinia pestis bacterium,has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Cearáto the Southeastern State ofMinas Gerais and another separated area at the State of Rio de Janeiro.This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019.Furthermore,we discuss how the interaction between Y.pestis and some rodent host species may play a role in the disease dynamics.The absence of human cases nowadays in Brazil does not mean that it was eradicated.The dynamics of plague in Brazil and in other countries where it was introduced during the 3rd pandemic are quite alike,alternating epidemics with decades of quiescence.Hence,it remains an important epidemic disease of global concern.The existence of a large animal reservoir and competent vectors demonstrate a need for continuous surveillance to prevent new outbreaks of this disease in humans.
文摘We investigated host and flea species composition across different habitats during dry and rainy seasons in the Western Usambara Mountains in Tanzania.During both seasons,similarity in flea species composition increased with an increase in the similarity in host species composition.Nevertheless,between-season within-habitat as well as within-season between-habitat similarity in host species composition was higher than similarity in flea species composition.Ordination of habitats according to their host and flea species composition demonstrated that the pattern of between-habitat similarity in both host and flea species composition varied seasonally.Despite the relatively rich mammal and flea fauna of the study region,the major contribution to variation in species composition between seasons and among habitats was due to a few species only.Flea assemblages on Lophuromys kilonzoi Verheyen et al.,2007 and Praomys delectorum Thomas,1910 in different habitats were equally similar in either season.In contrast,flea assemblages on Mastomys natalensis(Smith,1834)occurring in different habitats were more similar in the dry than in the rainy season,whereas the opposite was the case for fleas on Grammomys sp.In different hosts,the main differences in species composition of flea assemblages between seasons as well as among habitats were due to different flea species.Although our results support the earlier idea that parasite species composition is determined by both host species composition and habitat properties,the former appears to explain variance in flea species composition between localities in the tropics better than between localities in temperate and arid zones.
基金supported by the Major Program of National Natural Science Foundation of China(32090023).
文摘Climatic factors are closely associated with the occurrence of vector‐borne diseases,and they also influence the distribution of vectors.The occurrence of plague is closely related to the population dynamics of fleas and their host animals,as well as climatic conditions.This study focused on Xilingol League,utilizing climatic and flea index data from 2012 to 2021.Spearman correlation and"Boruta"importance analysis were conducted to screen for climatic variables.A generalized additive model(GAM)was employed to investigate the influence of climatic factors and rodent density on the flea index.GAM analysis revealed distinct trends in flea index among different rodent hosts.For Meriones unguiculatus,the flea index declined with increased density and with higher humidity,yet rose with greater lagged sunshine duration.For Spermophilus dauricus,an initial increase in flea index with density was observed,followed by a decrease,and a rise in the index was noted when ground temperatures were low.This study reveals the nonlinear interactions and lag effects among climatic factors,density,and flea index.Climatic factors and density variably influence the flea index of two Yersinia pestis hosts.This research advances the prediction and early warning efforts for plague control,providing a theoretical basis for rodent and flea eradication strategies.
文摘We tested for the effects of latitude and geographic range size(GRS)on body size,leg length,and sexual size dimorphism(SSD)across 103 species offleas,taking into account phylogenetic between-species relationships.When the data on body size were combined for males and females,the positive correlation between body size and latitude,but not GRS,was revealed.When the analysis was restricted to one sex only,the effect of latitude appeared to be non-significant for females,whereas male body size increased with an increase in latitude.Intraspecific body size variation was not associated with either the latitude or the latitudinal span of the geographic range,independently of which data subset was analyzed.No evidence of association between size-independent tibia length and latitude was found for either females,males,or both sexes combined.The degree of SSD decreased with a decrease in latitude but was not affected by GRS.We conclude that macroecological patterns might be manifested differently in males and females.This should be kept in mind while searching for these patterns.
基金supported by Israel Science Foundation(grant 548/23 to BRK and ISK).
文摘We studied spatial variation in the effects of environment and network size on species positions and roles in multiple flea–mammal networks from four biogeographic realms.We asked whether species positions(measured as species strength[SS],the degree of interaction specialization[d],and the eigenvector centrality[C])or the roles of fleas and their hosts in the interaction networks:(a)are repeatable/conserved within a flea or a host species;(b)vary in dependence on environmental variables and/or network size;and(c)the effects of environment and network size on species positions or roles in the networks depend on species traits.The repeatability analysis of species position indices for 441 flea and 429 host species,occurring in at least two networks,demonstrated that the repeatability of SS,d,and C within a species was significant,although not especially high,suggesting that the indices’values were affected by local factors.The majority of flea and host species in the majority of networks demonstrated a peripheral role.A value of at least one index of species position was significantly affected by environmental variables or network size in 41 and 36,respectively,of the 52 flea and 52 host species that occurred in multiple networks.In both fleas and hosts,the occurrence of the significant effect of environment or network size on at least one index of species position,but not on a species’role in a network,was associated with some species traits.
文摘Background:This scoping review provides a baseline summary of the current records of the ticks,fleas,and mites of public health importance that are present in Bangladesh.It summarizes their geographic distributions and reports the levels of their infestation of livestock,pets,wildlife,and humans,and the clinical and epidemiological studies pertinent to these vectors and their pathogens.Methods:Sixty-one articles were identified in a literature search,including 43 published since 2011.Results:Twelve articles contained reliable information on ticks and their associated hosts.However,informa-tion on fleas and mites in Bangladesh is very limited.Seventeen species of ixodid ticks that commonly parasitize peridomestic animals and can bite humans are described:Rhipicephalus microplus,R.appendiculatus,R.sanguineus,Haemaphysalis bispinosa,Hyalomma anatolicum,and Amblyomma testudinarium.Thirty-eight veterinary articles de-scribe livestock pathogens,including Babesia,Anaplasma,and Theileria,and the diseases they cause.Few of those studies used modern molecular techniques to identify these pathogens.Eleven articles reported human diseases or surveillance studies,10 from the last 10 years.Two country-wide serosurveys of 1,209 and 720 patients,us-ing Enzyme Linked Immunosorbent Assay(ELISA)and Indirect Immunofluorescence Assay(IFA),respectively,reported human exposure to Orientia tsutsugamushi(8.8%–23.7%),typhus and spotted-fever group rickettsiae(19.7%–66.6%),and Coxiella burnetii(3%).The seropositivity rates varied regionally.PCR-based studies con-firmed that febrile patients in Bangladesh may be infected with O.tsutsugamushi,Rickettsia typhi,Rickettsia felis,or Bartonella elizabethae.Only limited molecular research has been done with dogs and cats.These studies have reported PCR-confirmed canine infections with Babesia gibsoni(30%),Anaplasma bovis(58%),or Rickettsia monace-nis(14%,n=50),and feline infections with Rickettsia felis(21%,n=100).Similarly,fleas from cats tested positive for Rickettsia felis(20.6%).Conclusions:These findings indicate that diseases borne by non-mosquito vectors in Bangladesh urgently require more attention from public health,medical,and veterinary specialists to establish their true occurrence.
