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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Výskyt parazitů střev u selat ve stelivovém ustájení. / Prevalence of intestinal parasites by piglets in litter stabling.

NĚMCOVÁ, Klára January 2007 (has links)
Pooled faecal specimens of pigs were collected from the floor on two farms (A and B) and parasitologically examined. Investigations were divided into the five period: winter 2005 (A), spring 2005 (A), autumn 2005 (B), winter 2006 (B) and spring 2006 (B). In total, we collected 249 faecal specimens of pigs, of them 91 specimens were collected from farm A and 158 specimens from farm B. In farm A we collected 32 specimens from post-weaned piglets and in farm B 20 specimens from post-weaned piglets. Piglets were housed on litter stabling on both farms.
12

Výskyt parazitů zažívacího aparátu u telat ve stáji a ve venkovním odchovu. / Prevalence of gastrointestinal parasites in calves reared indors and in hutches.

MOTTLOVÁ, Markéta January 2008 (has links)
On two farms in a two-year period (spring 2005,autumn 2005, spring 2006, autumn 2006) calves faecal samples from the rectum or from the floor were obtained for parasitologic examination. A total of 560 samples from 209 calves were examined using the floatation method in Sheather's sugar solution. In positive samples the presence of Giardia intestinalis cysts, Cryptosporidium parvum, C. andersoni and Eimeria spp. oocysts was found. The infection by C. parvum was the highest from the 1st to the 3rd week and the infection by C. andersoni was the highest from the 7th to the 8th week of the calves age. In both breedings Coccidia Eimeria spp. was the most diagnosed, followed by G. intestinalis. With calves bred in stables by two a higher probability of parasitic infection was detected (46,9 %) compared to breeding of calves in outer individual boxes (17,6). The excrements of the calves were mainly of pasty or even of mushy consistence and the prevalence of the parasites was in most cases diagnosed in single infections.
13

Ocorrência de oocistos de Cryptosporidium spp. em águas superficiais na região metropolitana de Recife/PE

de Castro Lima Machado, Erilane January 2006 (has links)
Made available in DSpace on 2014-06-12T23:02:37Z (GMT). No. of bitstreams: 2 arquivo8569_1.pdf: 776272 bytes, checksum: afcf5071cf95d763da3e9f4ccb484cf5 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / A criptosporidiose tem se destacado como um problema de saúde pública e animal. A associação de casos da doença na população humana com a presença de Cryptosporidium spp. spp. em águas de consumo ou de recreação tem motivado a pesquisa do parasito no ambiente aquático. Este estudo objetivou a detecção de oocistos de Cryptosporidium spp. em águas superficiais na Região Metropolitana de Recife. A técnica de centrífugo- flutuação com solução saturada de cloreto de sódio foi usada para recuperação experimental de oocistos de Cryptosporidium spp.. Oocistos foram pesquisados em mananciais e no sistema de tratamento (água bruta e tratada) através da filtração das amostras em membrana, sendo identificados, sem prévia purificação, pelos métodos de coloração Kinyoun e imunofluorescência direta (IFD) associada ao 4 6 - Diamidino-2-Phenylindole (DAPI), analisando-se amostras durante 12 meses, nos períodos seco (Setembro à Fevereiro) e chuvoso (Março à Agosto). A qualidade da água foi avaliada através dos parâmetros microbiológicos (coliformes totais e fecais) e físicoquímicos (turbidez, pH). A técnica de PCR foi realizada para a pesquisa de oocistos de Cryptosporidium spp. de origem fecal a partir dos iniciadores gênero e espécie específicos, CPB-DIAGF/CPB-DIAGH e HB-1/HB-2, sendo o DNA extraído com proteinase K e solução de lise sob congelamento/descongelamento. Os resultados mostraram que a técnica de purificação garantiu um material mais limpo, porém o percentual de recuperação de oocistos variou de 39,0% a 98,4%. Na água tratada não se verificou a presença de oocistos de Cryptosporidium spp., enquanto nas amostras de água bruta foram encontradas estruturas álcool-ácido resistentes similares aos oocistos de Cryptosporidium spp. em 100% (05/05) dos locais e em 40% (24/60) das amostras analisadas pelo método Kinyoun, sendo a presença do parasito confirmada pela técnica IFD/DAPI em 40% (02/05) dos locais e em 5% (03/60) das amostras, com o número variando de 16 a 40 oocistos/l, e verificando sua ocorrência no período seco e chuvoso. Todas as amostras encontraram-se dentro dos limites microbiológicos e físico-químicos padrões, exceto no parâmetro turbidez. Os produtos de PCR foram obtidos apenas com o uso dos primers CPB-DIAGF/CPB-DIAGR, sendo o melhor perfil de amplificação observado quando 105 oocistos foram usados para a extração do DNA, e após o emprego dos protocolos de extração e de amplificação modificados. Conclui-se que a técnica de purificação de oocistos de Cryptosporidium spp. influencia os percentuais de recuperação. Os oocistos de Cryptosporidium spp. estão presentes em águas de rio na Região Metropolitana de Recife, sendo este o primeiro relato de Cryptosporidium spp. em mananciais de Pernambuco e do Nordeste. A técnica IFD/DAPI permite uma melhor identificação de oocistos de Cryptosporidium spp. em amostras de água, no entanto a coloração histoquímica demonstrou ser útil como uma técnica de triagem. As técnicas de extração e amplificação avaliadas neste estudo podem ser usadas para a pesquisa de Cryptosporidium spp. em amostras com elevado número de oocistos
14

An epidemiological study of cryptosporidiosis at the wildlife/livestock/human interface in Mpumalanga Province, South Africa

Abu Samra, Nada January 2013 (has links)
Cryptosporidium spp. is an oocyst-forming apicomplexan protozoan, which infects humans and a large variety of animals. Several species and genotypes are potentially zoonotic and ruminats are considered as an important source of infection. Pre-weaned calves are major hosts for zoonotic C. parvum, and show higher rates of infection than post-weaned or adult animals. Cryptosporidium infection has been demonstrated in a wide variety of wild animals, which may co tribute to environmental contamination. In sub-Saharan Africa, where the HIV infection prevalence is the highest in the world, high incidence of severe and even fatal Cryptosporidium infection have been reported in humans. This study investigated the epidemiology of Cryptosporidium spp. simultaneously in wildlife, indigenous cattle and young children living at the wildlife, livestock and human interface on the western boundary of the Kruger National Park (KNP) in Mpumalanga Province, South Africa. Initially, a pilot study was carried out to assess the zoonotic or anthroponotic importance of Cryptosporidium in diarrhoeic children in South Africa, representing the human group most likely to be infected. This geographically broad study involved hospitals from four provinces in South Africa. Stool samples from hospitalized diarrhoeic children from 0-1 year of age were analysed by microscopy (modified Ziehl-Neelsen (MZN) acid-fast staining) and molecular techniques: polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) and sequencing. An overall prevalence of Cryptosporidium infection of 12.2% was revealed, mainly involving species of anthroponotic origin, such as C. hominis (76%) and C. parvum of anthroponotic nature (20%). Only one species of uncertain zoonotic importance (C. meleagridis) was detected in this study. These findings were in accordance with reports from sub-Saharan Africa (including South Africa), where anthroponotic species of Cryptosporidium were responsible for most infections in humans. The study then concentrated on the public health importance of cryptosporidiosis at the wildlife/livestock/human interface of the KNP. Cryptosporidium oocysts were detected in elephant, impala and buffalo samples collected in three different study areas of the KNP; two located close to the boundaries of the KNP and a third one in the centre of the KNP. The MZN staining technique and an immunofluorescent antibody (IFA) test were applied to identify oocysts from faecal samples. The prevalence detected with MZN was higher than that detected with IFA, however both tests found a higher prevalence in elephants (25.8% and 4.2%, respectively) compared to the other species. The prevalence of Cryptosporidium in buffalo was 5.5% and 1.4% with MZN and IFA, respectively, and 4.2% and 1.8% respectively in impala. In the two study areas adjacent to the fence of KNP, the combined prevalence was significantly higher compared to the area in the centre of the KNP. The agreement between the MZN staining technique and the IFA test was assessed for each wildlife species; the estimates of kappa suggested moderate agreement in buffalo and impala and fair to poor agreement in elephant. The above results of were analysed further by the use of molecular techniques in order to reveal the species and genotypes of the parasite in wildlife and in addition faecal samples collected from post-weaned calves. A questionnaire was also conducted among farmers to investigate observed contacts between cattle and wildlife species in grazing areas outside and inside the KNP. Four of the 241 wildlife samples were PCR-positive (2.8% each in impala and buffalo and of 0.0% in elephant) and sequencing revealed the presence of C. ubiquitum in two impala and one buffalo and C. bovis in one buffalo. Cryptosporidium ubiquitum has been commonly found in a large number of animals, including humans. Among calf samples, 8% (4/51) were PCR-positive and were identified as C. andersoni (2/4) and C. bovis (2/4). The probability of contact between cattle and wildlife outside the KNP, observed by farmers, was higher for buffalo (Pr=0.6) and impala (Pr=0.46) than for elephant (Pr=0.04). This suggests that the detection of C. bovis in both cattle and buffalo might be due to direct or indirect contact between these two species. The detection of C. ubiquitum in wildlife, with its zoonotic potential, suggests that Cryptosporidium may be of public health concern for people living at the interface. We further investigated the prevalence of Cryptosporidium infection in cattle and humans, this time targeting younger (pre-weaned) calves and children. Children <5 years were sampled at six rural clinics within the same interface and stool samples were screened by the MZN staining technique. All MZN-positive and suspicious samples of children and samples of 36 calves within the age of 0-4 months were analysed by nested PCR. Eight of the 143 children (5.6%) were positive on PCR, and sequencing identified predominantly C. hominis, while one sample was identified as C. meleagridis. Eleven of the 36 calf samples (30.5%) were PCR-positive and were identified as C. bovis and C. ryanae. Due to limited resources, molecular analysis could not be performed on more samples. Variables such as source of drinking water, age and contact with animals for children, were analysed as potential risk factors for humans and cattle; however, none were statistically significant. In conclusion, the prevalence of Cryptosporidium detected in human and wildlife was low compared to that reported in other studies in Africa. The species and genotypes detected in humans were predominantly of anthroponotic nature; however, the isolation of C. Ubiquitum from buffalo and impala shows that at least one species of zoonotic importance is present at the wildlife/livestock/human interface. The prevalence of HIV/AIDS in our study area is one of the highest worldwide; therefore the potential public health importance of this parasite should be investigated further. / Thesis (PhD)--University of Pretoria, 2013. / gm2013 / Production Animal Studies / unrestricted
15

Feline Parasitism:  Parasite Prevalence and Evaluation of New Immunoassays for Giardia and Cryptosporidium

Monti, Katelynn A. 13 September 2017 (has links)
Cats are infected with a variety of internal parasites, some of which are zoonotic. Therefore, being able to effectively detect and determine prevalence of internal parasites in cats is important for both feline and human health. Some parasites are easier to detect than others. Diagnosing Giardia duodenalis and Cryptosporidium spp. can be difficult because cysts and oocysts shed in the feces are small, shed intermittently, and require a trained technician to consistently identify them. As a result, infections with these protozoan parasites can be missed. Fecal immunoassays detect antigens in feces and can have increased sensitivity when compared to traditional microscopic techniques, but still do not detect every infection. The current reference standard is an immunoassay known as the direct immunofluorescent assay, but it requires expensive equipment and a long incubation period. As a result, two prototype lateral flow fecal immunoassays, the Cryptosporidium EZ VUE and Giardia EZ VUE, designed by TECHLAB® Inc were evaluated for the ability to detect G. duodenalis and Cryptosporidium spp. infections in cats because they are cheap, easy to use, easy to store and easy to interpret. In addition, samples were examined using a 33% zinc sulfate (ZnSO4) centrifugal fecal flotation procedure and the MERIFLUOR® Cryptosporidium/Giardia direct immunofluorescent assay (IFA), which served as the reference test. Other internal parasites found on the centrifugal fecal flotation with zinc sulfate were recorded to determine prevalence. Both EZ VUE fecal immunoassays demonstrated potential in diagnosing infections in cats when compared to centrifugal fecal flotation and the reference. Additionally, a variety of other internal parasites were identified. This included several potentially zoonotic species including Spirometra mansonoides, Ancylostoma sp. and Toxocara cati, which was also the most commonly identified species of parasite. Additionally, it was determined that several factors may contribute to higher prevalence of parasites especially in cats with the status of stray or feral. / M. S.
16

Ocorrência e remoção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em Reatores Anaeróbios de Fluxo Ascendente e Manta de Lodo (UASB) operando com esgoto sanitário e águas negras simuladas / Occurrence and removal of Giardia spp. and Cryptosporidium spp. in Upflow Anaerobic Sludge Blanket Reactors (UASB) operating with sewage and simulated black water

Fernanda Queiroz Valdez 09 September 2016 (has links)
As doenças de veiculação hídrica são uma preocupação no mundo todo, e tem aumentado cada vez mais o interesse nos estudos relacionados aos protozoários Cryptosporidium spp. e Giardia spp.. A presença de protozoários em águas de abastecimento está vinculada ao lançamento de esgoto nos mananciais, de modo que o tratamento de esgotos sanitários é de extrema importância para reduzir o risco de surtos de protozooses. Este trabalho avaliou a ocorrência e a possibilidade de remoção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em dois reatores UASB, um piloto e um em escala plena, operados com esgoto sanitário e um TDH de aproximadamente 8h, e um reator UASB piloto, operado com água negra simulada e um TDH aproximado de três dias. Nos dois reatores operados com esgoto sanitário as remoções foram semelhantes. A média de DQO total afluente, no reator piloto e no de escala plena, foi de 271 e 410 mg/L, respectivamente, e as remoções médias de DQO foram de 50,62 e 45,80%, respectivamente. Com relação aos exames parasitológicos, quase não houve remoção em ambos os reatores e, na maior parte dos casos, o número de (oo)cistos detectados no efluente foi maior do que no afluente. Já no reator piloto operado com águas negras, foram observadas remoções mais elevadas. A DQO total afluente desse reator variou de 837 a 3269 mg/L e a remoção média observada foi de 71,22%. Neste reator também foram observadas maiores remoções de (oo)cistos, sendo que a remoção de cistos Giardia spp. variou de 67,73 a 93,69% e, em um dos ensaios, foi observada uma remoção de 70% de oocistos de Cryptosporidium spp. Acredita-se que o melhor desempenho desse reator se deve ao seu elevado tempo de detenção hidráulico. Foi avaliada, ainda, a ocorrência de (oo)cistos no lodo dos três reatores, resultando em valores bastante elevados, da ordem de 105 cistos/g de massa seca, em todos eles. De qualquer modo, em todos os reatores avaliados, mesmo o que apresentou as maiores eficiências, o efluente ainda apresentava altas concentrações de poluentes, necessitando de um pós-tratamento para a remoção dos remanescentes de matéria orgânica, sólidos e patógenos. / The waterborne diseases are a concern worldwide, and has grown more and more interest in studies related to the protozoa Cryptosporidium spp. and Giardia spp. The presence of protozoa in drinking water is related to the release of sewage in water sources. So that, the sewage treatment is extremely important to reduce the risk of outbreaks protozoa. This study evaluated the occurrence and the possibility of removal of Giardia spp. and Cryptosporidium spp. in two UASB reactors, a pilot and a full-scale, operated with sewage and a HRT of 8 hours, approximately, and a pilot UASB reactor, operated with simulated black water and an approximate HRT of three days. Removals were similar in both reactors operated with sewage. The average influent total COD, in pilot and full scale reactors, was 271 and 410 mg/L, respectively, and the average COD removal were 50.62 and 45.80%, respectively. With the parasitological test, there was almost no removal in both reactors and, in most cases, the number of (oo)cysts detected in the effluent was higher than in the influent. In the pilot reactor operated with black water, higher removals were observed. The total COD influent of this reactor ranged from 837 to 3269 mg/L and the average removal observed was 71.22%. In this reactor (oo)cysts removals were also higher, and the removal of Giardia cysts ranged from 67.73 to 93.69%, and in one of the trials, a 70% removal of Cryptosporidium spp was observed. It is believed that the best performance of this reactor is due to its high hydraulic retention time. The occurrence of (oo)cysts in the sludge of the three reactors was also evaluated, resulting in very high values of the order of 105 cysts/g of dry weight, in all of them. Anyway, in all this reactor, even the one with the highest efficiency, the effluent still had high concentrations of pollutants, necessitating a post treatment for the removal of remaining organic matter, solids and pathogens.
17

Bioagentes patogênicos em águas residuárias: destaque para giardia spp., cryptosporidium spp. bactérias indicadoras e vírus entéricos / Patogenics agents in wastewater: emphasis in Giardia spp., Cryptosporidium spp., indicator bacteria and enteric viruses

Tonani, Karina Aparecida de Abreu 21 June 2011 (has links)
Esgotos urbanos constituem compartimentos ambientais que favorecem a emergência e re-emergência enfermidades de veiculação hídrica. Este estudo objetivou analisar cistos de Giardia spp., oocistos de Cryptosporidium spp., assim como cistos, ovos e larvas de outros protozoários e helmintos patogênicos; Coliformes Totais e Termotolerantes, Rotavírus e Adenovírus em amostras de esgoto bruto e tratado da Estação de Tratamento de Esgoto de Ribeirão Preto - SP. As coletas de esgoto foram realizadas no ponto de entrada e no ponto de saída da ETE-Ribeirão Preto/SP. As análises de cistos de Giardia spp. e oocistos de Cryptosporidium spp. foram realizados pelo Método 1623 da EPA. Ovos, cistos e larvas de outros protozoários e helmintos foram analisados pelo Método de Sedimentação proposto pela CETESB (1989). A análise de coliformes totais e termotolerantes foi realizada pela Técnica de Tubos Múltiplos (Colilert®). A análise de vírus foi realizada através do Teste de Elisa com o KIT da RIDASCREEN® Enzimaimunoensaio. Os resultados obtidos revelaram que a concentração de Giardia spp. no esgoto bruto variou de 120 a 2200 cistos/L, já no esgoto tratado essa concentração variou de 0,45 a 3,5 cistos/L. Com relação aos oocistos de Cryptosporidium spp. a concentração no esgoto bruto variou de não detectável a 28,9 oocistos/L e no esgoto tratado as concentrações variaram de não detectável a 1,05 oocistos/L. O processo de lodos ativados na ETE-RP promoveu uma remoção parcial de parasitas, tais como: Endolimax nana, Entamoeba coli, Entamoeba hystolitica, Ancylostoma sp., Ascaris sp. Fasciola hepatica e Strongyloides stercoralis, cujo fator de redução variou entre 18,2 e 100%. Pode-se observar que houve diferença estatisticamente significante entre o número mais provável de coliformes totais e termotolerantes no esgoto bruto e esgoto tratado, mostrando uma redução na concentração desses organismos indicadores após o tratamento do esgoto na ETE-Ribeirão Preto/SP. Não houve correlação significativa entre as concentrações de coliformes totais e termotolerantes em relação à concentração de cistos de Giardia spp. e oocistos de Cryptosporidium spp.. A análise de vírus mostrou resposta positiva para Rotavirus e Adenovirus em todas as amostras analisadas (esgoto bruto e tratado), mostrando menor absorvância no esgoto tratado. Os resultados obtidos contribuem para a identificação e caracterização de microorganismos de veiculação hídrica no esgoto tratado na ETE-RP, fornecendo dados úteis para a definição de políticas públicas de saneamento, referentes ao controle da qualidade microbiológica do esgoto no país. / Sewage treatment is still precarious in many Brazilian cities, which has contributed to the emergence and re-emergence of waterborne diseases. This study analyzed Giardia spp. cysts and Cryptosporidium spp. oocysts, as well as cysts, eggs and larvae of other protozoa and helminthes. Also part of the study were total and thermotolerant coliforms, Rotavirus and Adenovirus in samples of raw and treated sewage of the Sewage Treatment Station (ETE) of Ribeirão Preto, SP, Brazil. Sewage samples were taken at the points of entry and exit of the ETE, Ribeirão Preto. Analyses of Giardia spp. cysts and Cryptosporidium spp. oocysts were performed through the EPA\'s method 1623. Eggs, cysts and larvae of other protozoa and helminthes were analyzed utilizing the method of sedimentation as proposed by CETESB (1989). Analyses of total and thermotolerant coliforms were performed using the Multiple Tube method (Colilert®). Viral analyses were performed through the RIDASCREEN® enzyme immunoassay ELISA test kit. The results revealed that the concentration of Giardia spp. in raw sewage varied from 120 to 2,200 cysts/L; this concentration varied from 0.45 to 3.5 cysts/L in treated sewage. The concentration of Cryptosporidium spp. oocysts in raw sewage varied from non-detectable to 28.9 oocysts/L and from non-detectable to 1.05 oocysts/L in treated sewage. The activated sludge process used in ETE promoted a partial removal of parasites such as: Endolimax nana, Entamoeba coli, Entamoeba hystolitica, Ancylostoma sp., Ascaris sp. Fasciola hepatica and Strongyloides stercoralis. Reduction factors varied from 18.2 to 100%. A statistically significant difference was observed between the most probable number of total and thermotolerant coliforms in raw and treated sewage, showing a reduction in the concentration of these indicators after the treatment of sewage in ETE, Ribeirão Preto. No statistically significant correlation was found between the concentrations of total and thermotolerant coliforms in relation to the concentration of Giardia cysts spp. and Cryptosporidium spp. oocysts. Analyzing viruses showed positive responses for Rotavirus and Adenovirus in all the studied samples (raw and treated sewage), with a smaller absorbance in the treated sewage. The results contribute to the identification and evaluation of the prevalence of waterborne microorganisms in treated sewage in ETE, Ribeirão Preto, providing useful data for the definition of public policies for sanitation concerning microbiological quality control in Brazil\'s sewage.
18

Importância de mamíferos neotropicais na epidemiologia de protozooses: diagnóstico, caracterização molecular e aspectos ecológicos da infecção por Giardia e Cryptosporidium / Importance of neotropical mammals in the epidemiology of protozoosis: diagnosis, molecular characterization and ecological aspects of infection by Giardia and Cryptosporidium

Santos, Renata Carolina Fernandes 07 October 2011 (has links)
Giardia e Cryptosporidium são protozoários cosmopolitas cuja epidemiologia é especialmente importante devido ao seu expressivo potencial zoonótico. Animais silvestres são frequentemente relatados como reservatórios da giardiose e criptosporidiose humanas, todavia, são escassas as evidências sobre sua real importância na manutenção e disseminação destas protozooses. No intuito de avaliar a ocorrência e determinar os genótipos responsáveis pela infecção de mamíferos neotropicais, 452 amostras fecais procedentes de 52 diferentes espécies, in situ e ex situ, de sete localidades distintas foram avaliadas por métodos de diagnóstico microscópico, seguidos por técnicas moleculares de amplificação (Nested PCR), sequenciamento e caracterização genotípica. Os resultados revelaram prevalência aparente de 6,2% para Giardia spp. e de 4,8% para Cryptosporidium spp. (n=343). Dezessete diferentes espécies de mamíferos silvestres foram positivas, sendo 11 para Giardia spp., nove para Cryptosporidium spp. e três para ambos os protozoários. A caracterização molecular revelou a predominante presença de genótipos zoonóticos em mamíferos cativos (Giardia duodenalis genótipo AI) e de genótipos hospedeiro-específicos em animais de vida livre (Cryptosporidium sp. rat genotype III e Cryptosporidium wrairi). Foram também identificados Giardia duodenalis genótipo D em cachorro-do-mato Cerdocyon thous e Cryptosporidium sp. deer mouse genotype IV em bugio-preto Alouatta caraya, ambos mantidos em cativeiro. Aspectos ecológicos, como habitat, guilda trófica, estratégia do uso do ambiente e influência antrópica, foram considerados relevantes para a ocorrência dos parasitas. Tais achados demonstraram que animais silvestres podem ser infectados por genótipos zoonóticos e específicos dos agentes, o que revela a importância de estudos envolvendo esta abordagem para sugerir possíveis relações entre os protozoários, hospedeiros humanos, animais domésticos e silvestres perante diferentes características ambientais. / Giardia and Cryptosporidium are cosmopolitan protozoans whose epidemiology is especially important due to its significant zoonotic potencial. Wild animals are often reported as reservoirs of human giardiosis and cryptosporidiosis, however, there is little evidence about their real importance in the maintenance and dissemination of these protozoosis. In order to evaluate the occurrence and determine the genotypes responsible for neotropical mammals infection, 452 fecal samples of 52 different species, in situ and ex situ, of seven locations were evaluated by microscopic methods of diagnosis, followed by molecular amplification (Nested PCR), sequencing and genotypic chacacterization techniques. The results revealed an apparent prevalence of 6,2% for Giardia spp. and 4,8% for Cryptosporidium spp. (n=343). Seventeen different species of wild mammals were positive, 11 for Giardia spp., nine for Cryptosporidium spp. and three for both protozoans. Molecular characterization shows predominant presence of zoonotic genotypes in captive mammals (Giardia duodenalis genotype AI) and host-specific genotypes in free-living animals (Cryptosporidium sp. rat genotype III and Cryptosporidium wrairi). Giardia duodenalis genotype D in crab-eating fox Cerdocyon thous and Cryptosporidium sp. deer mouse genotype IV in black howler monkey Alouatta caraya, both in captivity, were also identified. Ecological aspects, like habitat, trophic guilds, strategy of using the environment and human influence, were considered relevant to occurrence of the parasites. These findings could demonstrate wild mammals can be infected by zoonotic and specific genotypes of agents, which shows the importance of studies using this approach to suggest possible relationships between protozoans, human hosts, domestic animals and wildlife facing different environmental characteristics.
19

Importância de mamíferos neotropicais na epidemiologia de protozooses: diagnóstico, caracterização molecular e aspectos ecológicos da infecção por Giardia e Cryptosporidium / Importance of neotropical mammals in the epidemiology of protozoosis: diagnosis, molecular characterization and ecological aspects of infection by Giardia and Cryptosporidium

Renata Carolina Fernandes Santos 07 October 2011 (has links)
Giardia e Cryptosporidium são protozoários cosmopolitas cuja epidemiologia é especialmente importante devido ao seu expressivo potencial zoonótico. Animais silvestres são frequentemente relatados como reservatórios da giardiose e criptosporidiose humanas, todavia, são escassas as evidências sobre sua real importância na manutenção e disseminação destas protozooses. No intuito de avaliar a ocorrência e determinar os genótipos responsáveis pela infecção de mamíferos neotropicais, 452 amostras fecais procedentes de 52 diferentes espécies, in situ e ex situ, de sete localidades distintas foram avaliadas por métodos de diagnóstico microscópico, seguidos por técnicas moleculares de amplificação (Nested PCR), sequenciamento e caracterização genotípica. Os resultados revelaram prevalência aparente de 6,2% para Giardia spp. e de 4,8% para Cryptosporidium spp. (n=343). Dezessete diferentes espécies de mamíferos silvestres foram positivas, sendo 11 para Giardia spp., nove para Cryptosporidium spp. e três para ambos os protozoários. A caracterização molecular revelou a predominante presença de genótipos zoonóticos em mamíferos cativos (Giardia duodenalis genótipo AI) e de genótipos hospedeiro-específicos em animais de vida livre (Cryptosporidium sp. rat genotype III e Cryptosporidium wrairi). Foram também identificados Giardia duodenalis genótipo D em cachorro-do-mato Cerdocyon thous e Cryptosporidium sp. deer mouse genotype IV em bugio-preto Alouatta caraya, ambos mantidos em cativeiro. Aspectos ecológicos, como habitat, guilda trófica, estratégia do uso do ambiente e influência antrópica, foram considerados relevantes para a ocorrência dos parasitas. Tais achados demonstraram que animais silvestres podem ser infectados por genótipos zoonóticos e específicos dos agentes, o que revela a importância de estudos envolvendo esta abordagem para sugerir possíveis relações entre os protozoários, hospedeiros humanos, animais domésticos e silvestres perante diferentes características ambientais. / Giardia and Cryptosporidium are cosmopolitan protozoans whose epidemiology is especially important due to its significant zoonotic potencial. Wild animals are often reported as reservoirs of human giardiosis and cryptosporidiosis, however, there is little evidence about their real importance in the maintenance and dissemination of these protozoosis. In order to evaluate the occurrence and determine the genotypes responsible for neotropical mammals infection, 452 fecal samples of 52 different species, in situ and ex situ, of seven locations were evaluated by microscopic methods of diagnosis, followed by molecular amplification (Nested PCR), sequencing and genotypic chacacterization techniques. The results revealed an apparent prevalence of 6,2% for Giardia spp. and 4,8% for Cryptosporidium spp. (n=343). Seventeen different species of wild mammals were positive, 11 for Giardia spp., nine for Cryptosporidium spp. and three for both protozoans. Molecular characterization shows predominant presence of zoonotic genotypes in captive mammals (Giardia duodenalis genotype AI) and host-specific genotypes in free-living animals (Cryptosporidium sp. rat genotype III and Cryptosporidium wrairi). Giardia duodenalis genotype D in crab-eating fox Cerdocyon thous and Cryptosporidium sp. deer mouse genotype IV in black howler monkey Alouatta caraya, both in captivity, were also identified. Ecological aspects, like habitat, trophic guilds, strategy of using the environment and human influence, were considered relevant to occurrence of the parasites. These findings could demonstrate wild mammals can be infected by zoonotic and specific genotypes of agents, which shows the importance of studies using this approach to suggest possible relationships between protozoans, human hosts, domestic animals and wildlife facing different environmental characteristics.
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Ocorrência e remoção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em Reatores Anaeróbios de Fluxo Ascendente e Manta de Lodo (UASB) operando com esgoto sanitário e águas negras simuladas / Occurrence and removal of Giardia spp. and Cryptosporidium spp. in Upflow Anaerobic Sludge Blanket Reactors (UASB) operating with sewage and simulated black water

Valdez, Fernanda Queiroz 09 September 2016 (has links)
As doenças de veiculação hídrica são uma preocupação no mundo todo, e tem aumentado cada vez mais o interesse nos estudos relacionados aos protozoários Cryptosporidium spp. e Giardia spp.. A presença de protozoários em águas de abastecimento está vinculada ao lançamento de esgoto nos mananciais, de modo que o tratamento de esgotos sanitários é de extrema importância para reduzir o risco de surtos de protozooses. Este trabalho avaliou a ocorrência e a possibilidade de remoção de cistos de Giardia spp. e oocistos de Cryptosporidium spp. em dois reatores UASB, um piloto e um em escala plena, operados com esgoto sanitário e um TDH de aproximadamente 8h, e um reator UASB piloto, operado com água negra simulada e um TDH aproximado de três dias. Nos dois reatores operados com esgoto sanitário as remoções foram semelhantes. A média de DQO total afluente, no reator piloto e no de escala plena, foi de 271 e 410 mg/L, respectivamente, e as remoções médias de DQO foram de 50,62 e 45,80%, respectivamente. Com relação aos exames parasitológicos, quase não houve remoção em ambos os reatores e, na maior parte dos casos, o número de (oo)cistos detectados no efluente foi maior do que no afluente. Já no reator piloto operado com águas negras, foram observadas remoções mais elevadas. A DQO total afluente desse reator variou de 837 a 3269 mg/L e a remoção média observada foi de 71,22%. Neste reator também foram observadas maiores remoções de (oo)cistos, sendo que a remoção de cistos Giardia spp. variou de 67,73 a 93,69% e, em um dos ensaios, foi observada uma remoção de 70% de oocistos de Cryptosporidium spp. Acredita-se que o melhor desempenho desse reator se deve ao seu elevado tempo de detenção hidráulico. Foi avaliada, ainda, a ocorrência de (oo)cistos no lodo dos três reatores, resultando em valores bastante elevados, da ordem de 105 cistos/g de massa seca, em todos eles. De qualquer modo, em todos os reatores avaliados, mesmo o que apresentou as maiores eficiências, o efluente ainda apresentava altas concentrações de poluentes, necessitando de um pós-tratamento para a remoção dos remanescentes de matéria orgânica, sólidos e patógenos. / The waterborne diseases are a concern worldwide, and has grown more and more interest in studies related to the protozoa Cryptosporidium spp. and Giardia spp. The presence of protozoa in drinking water is related to the release of sewage in water sources. So that, the sewage treatment is extremely important to reduce the risk of outbreaks protozoa. This study evaluated the occurrence and the possibility of removal of Giardia spp. and Cryptosporidium spp. in two UASB reactors, a pilot and a full-scale, operated with sewage and a HRT of 8 hours, approximately, and a pilot UASB reactor, operated with simulated black water and an approximate HRT of three days. Removals were similar in both reactors operated with sewage. The average influent total COD, in pilot and full scale reactors, was 271 and 410 mg/L, respectively, and the average COD removal were 50.62 and 45.80%, respectively. With the parasitological test, there was almost no removal in both reactors and, in most cases, the number of (oo)cysts detected in the effluent was higher than in the influent. In the pilot reactor operated with black water, higher removals were observed. The total COD influent of this reactor ranged from 837 to 3269 mg/L and the average removal observed was 71.22%. In this reactor (oo)cysts removals were also higher, and the removal of Giardia cysts ranged from 67.73 to 93.69%, and in one of the trials, a 70% removal of Cryptosporidium spp was observed. It is believed that the best performance of this reactor is due to its high hydraulic retention time. The occurrence of (oo)cysts in the sludge of the three reactors was also evaluated, resulting in very high values of the order of 105 cysts/g of dry weight, in all of them. Anyway, in all this reactor, even the one with the highest efficiency, the effluent still had high concentrations of pollutants, necessitating a post treatment for the removal of remaining organic matter, solids and pathogens.

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