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in-situ monitoring of cryptosporidium parvum oocyst surface adhesion using atr-ftir spectroscopy.surface chemistry and molecular interaction mechanisms of cryptosporidium parvum oocysts with a znse internal reflection element (ire) surface were investigated as a function of ph and ionic strength in nacl and cacl(2) background electrolyte using in-situ atr-ftir spectroscopy. since the surface properties of oocysts play an important role in adhesion behavior, the effects of surface modifications that are commonly employed to inactivate the pathogen for laboratory studies, including viable (co ...200919269797
genetic classification of cryptosporidium isolates from humans and calves in slovenia.to assess the importance of cattle as a source of human cryptosporidial infections in slovenia, cryptosporidium isolates from calves and humans with cryptosporidiosis were characterized genetically by direct dna sequencing, targeting a variable region of the 60 subtypes', were identified, of which 7 were novel. in humans, c. hominis ia (subtype iaa17r3) and ib (iba10g2) and cryptosporidium parvum iia (iiaa9g1r1, iiaa11g2r1, iiaa13r1, iiaa14g1r1, iiaa15g1r1, iiaa15g2r1, iiaa16g1r1, iiaa17g1r1 and ...200818664309
effect of nitazoxanide on cryptosporidiosis in experimentally infected neonatal dairy calves.cryptosporidium is a zoonotic protozoan that is most often diagnosed in association with diarrhea in 1- to 3-wk-old dairy calves. there are neither consistently effective nor approved antimicrobial drugs for treatment in animals. the objective of this study was to test nitazoxanide (ntz) as a treatment for cryptosporidiosis in experimentally infected dairy calves. a randomized, controlled, and blinded trial was performed using holstein bull calves obtained from a large commercial dairy. all birt ...200919307646
molecular epidemiology of cryptosporidiosis: an update.molecular tools have been developed to detect and differentiate cryptosporidium at the species/genotype and subtype levels. these tools have been increasingly used in characterizing the transmission of cryptosporidium spp. in humans and animals. results of these molecular epidemiologic studies have led to better appreciation of the public health importance of cryptosporidium species/genotypes in various animals and improved understanding of infection sources in humans. geographic, seasonal and s ...201019358845
prevalence and associated management factors of cryptosporidium shedding in 50 swedish dairy herds.cryptosporidium parvum is a protozoan parasite causing diarrhoea in young calves. this cross-sectional study was performed to estimate the prevalence of cryptosporidium infected herds in a sample of swedish dairy herds and to identify potential risk factors associated with shedding of oocysts. fifty dairy herds, selected by stratified random sampling, were included. the herds were visited once during the indoor seasons of 2005-2006 and 2006-2007. faecal samples were collected from 10 calves, 10 ...200919443061
cryptosporidium parvum dna replication in cell-free culture.the lack of robust methods for culturing cryptosporidium parasites remains a major challenge and is hampering efforts to screen for anti-cryptosporidial drugs. in existing culture methods, monolayers of mammalian epithelial cells are inoculated with oocysts. the system supports an initial phase of asexual proliferation of the parasite. for reasons that are not clear, development rapidly declines within 2-3 days. the unexpected report of cryptosporidium parvum culture in the absence of host cells ...200919463037
detection of cryptosporidium spp. and giardia duodenalis in surface water: a health risk for humans and animals.the objective of the present study was to determine the degree of contamination by cryptosporidium spp. and giardia duodenalis in a river basin in a livestock farming area in galicia (nw, spain). water samples (50 l) were collected at 22 points in the main basin (including 5 recreational areas), and at the source and mouth of the 3 most important rivers and at the mouth of a smaller, secondary river. faecal samples were collected from dairy cattle selected at random from 18 herds farmed in the a ...200919576608
prevalence and molecular characterization of cryptosporidium spp. in dairy cattle in south bohemia, the czech republic.a total of 995 samples from slaughtered dairy cattle (6 months and older) were collected during two consecutive years (from 2007 to 2008), stained by aniline-carbol-methyl violet and examined microscopically. dna was extracted from cryptosporidium positive samples and from 200 randomly selected microscopically negative samples. nested pcr was performed to amplify the partial ssu rrna and gp60 genes of cryptosporidium that were subsequently digested by sspi, vspi and mboii restriction enzymes to ...200919616383
risk factors associated with cryptosporidium parvum infection in cattle.a 2-year, cross-sectional study was conducted to identify risk factors for cryptosporidium sp. infection in bovine farms in central italy. faecal samples were collected on 248 farms, from 2024 calves and analysed using elisa and immunofluorescent assay (ifa) commercial kits. in all 101 samples confirmed to be positive with ifa, the aetiological agent was identified as cryptosporidium parvumand a large genetic variability was detected by subtype analysis. the prevalence of farm infection ranged f ...200918771517
transient transfection of cryptosporidium parvum using green fluorescent protein (gfp) as a marker.cryptosporidium parvum is a protozoan parasite that infects a variety of mammals. the parasite has been shown to harbor a dsrna virus (cpv) and in the present study, we have developed a cpv transient transfection system for this parasite by using green fluorescent protein (gfp) to replace the partial gene encoding region of the larger dsrna (cpv-l) and the smaller dsrna (cpv-s) virus. two viral rna-mediated transfection vectors: pcpvl-gfp and pcpvs-gfp were successfully constructed and both in v ...200919631239
genetic characterization of cryptosporidium parvum from calves by mutation scanning and targeted sequencing--zoonotic implications.this study explored the genetic make-up of cryptosporidium in fecal samples from 268 individual calves on pasture-based dairy farms in three regions of victoria, australia. an integrated approach, using pcr-coupled single-strand conformation polymorphism, targeted sequencing and phylogenetic analysis, was employed to classify the genetic variants (i.e. genotypes and subgenotypes) of cryptosporidium parvum present in 124 (46.3%) samples and to infer their zoonotic potential. genotypic and subgeno ...200919637220
a multiplex polymerase chain reaction assay to simultaneously distinguish cryptosporidium species of veterinary and public health concern in cattle.four species of cryptosporidium are routinely found in cattle: cryptosporidium parvum, cryptosporidium bovis, cryptosporidium ryanae, and cryptosporidium andersoni. it is important to determine the species of cryptosporidium in infected cattle because c. parvum is the only serious pathogen for humans as well as cattle. identification of cryptosporidium species and genotypes currently relies on molecular methods such as polymerase chain reaction (pcr) followed by restriction fragment length polym ...200919713046
evidence-based semiquantitative methodology for prioritization of foodborne zoonoses.to prioritize an extended list of food- and water-borne zoonoses to allow food safety authorities to focus on the most relevant hazards in the food chain.200919715429
studies on zoonotic cryptosporidiosis parvum in ismailia governorate, egypt.a total of 390 stool samples from children less than 8 years old attending the mohp central hospital in ismailia district were examined for cryptosporidiosis. stools were subjected to direct wet smear method and sheather's sugar flotation and stained with modified z.n. among the 390 children 204 were diarrheic of whom c. parvum was positive in 68 (33.3%). the highest infection rate was 26/46 among children less than 2 months, 40/150 among children less than 2 years and 2/8 among children less th ...200919795755
prevalence, prediction and risk factors of enteropathogens in normal and non-normal faeces of young dutch dairy calves.between january and april 2007, 424 calves under 22 days of age from 108 dutch dairy herds were sampled to estimate the prevalence of non-normal faeces ('custard-like'-yellowish-coloured with custard consistency or diarrhoea: watery-like faeces) and the shedding of enteropathogens escherichia coli k99 (e. coli), coronavirus, cryptosporidium parvum (c. parvum), rotavirus and clostridium perfringens (cl. perfringens). in addition, information was collected on animal characteristics and herd-manage ...201019819574
cryptosporidium spp. in wild, laboratory, and pet rodents in china: prevalence and molecular characterization.to understand the prevalence of cryptosporidium infection in rodents in china and to assess the potential role of rodents as a source for human cryptosporidiosis, 723 specimens from 18 rodent species were collected from four provinces of china and examined between august 2007 and december 2008 by microscopy after using sheather's sugar flotation and modified acid-fast staining. cryptosporidium oocysts were detected in 83 specimens, with an overall prevalence of 11.5%. phodopus sungorus, phodopus ...200919820152
determination of the specificities of monoclonal and polyclonal antibodies to neospora, toxoplasma and cryptosporidium by fluorescent antibody test (fat).flourescent antibody test (fat) was applied to determine the cross-reactivities of monoclonal (mab), polyclonal (pab) antibodies to neospora, toxoplasma and cryptosporidium and antisera from cattle naturally infected with neospora canium against antigens from a number of sources. both mab and pab to neospora reacted strongly (fat titre up to 2560) with the homologous antigens and demonstrated weak titre (80) or no reaction with both toxoplasma and cryptosporidium antigens. also mab and pab to to ...200819287361
evidence for mucin-like glycoproteins that tether sporozoites of cryptosporidium parvum to the inner surface of the oocyst wall.cryptosporidium parvum oocysts, which are spread by the fecal-oral route, have a single, multilayered wall that surrounds four sporozoites, the invasive form. the c. parvum oocyst wall is labeled by the maclura pomifera agglutinin (mpa), which binds galnac, and the c. parvum wall contains at least two unique proteins (cryptosporidium oocyst wall protein 1 [cowp1] and cowp8) identified by monoclonal antibodies. c. parvum sporozoites have on their surface multiple mucin-like glycoproteins with ser ...201019949049
the first detection of cryptosporidium deer-like genotype in cattle in japan.the general perception is that cattle are major reservoirs for cryptosporidium parvum infections in humans and that c. parvum is a major cause of diarrhea and production loss in cattle. adult cattle may play an important role as cryptic carrier of the infection. cryptosporidium spp. in asymptomatic adult dairy cattle from some farms around osaki area, miyagi prefecture, japan, was examined on a field visit during august, 2007, by polymerase chain reaction techniques for detection, genotyping, an ...200918989700
triazole inhibitors of cryptosporidium parvum inosine 5'-monophosphate dehydrogenase.cryptosporidium parvum is an important human pathogen and potential bioterrorism agent. this protozoan parasite cannot salvage guanine or guanosine and therefore relies on inosine 5'-monophosphate dehydrogenase (impdh) for biosynthesis of guanine nucleotides and hence for survival. because c. parvum impdh is highly divergent from the host counterpart, selective inhibitors could potentially be used to treat cryptosporidiosis with minimal effects on its mammalian host. a series of 1,2,3-triazole c ...200919624136
cryptosporidiosis in people: it's not just about the cows.cryptosporidiosis is one of the most common causes of infectious diarrhea in people. although dairy calves are high-risk hosts, the role of other livestock, pets, and humans in the disease should not be underestimated. some cryptosporidium species and strains are specific to people, others are specific to animals while some are zoonotic pathogens. cryptosporidium hominis is the species responsible for the majority of human cases in the united states, sub-saharan africa, and asia, while cryptospo ...201020041989
cryptosporidium recovered from musca domestica, musca sorbens and mango juice accessed by synanthropic flies in bahirdar, ethiopia.the study was conducted to determine the role of house flies, musca domestica and musca sorbens to carry cryptosporidium species in natural environment and filth flies potential for contamination of food item they visited using acid-fast stain technique. cryptosporidium was identified from flies collected in dairy cow barns, butchery, market and defecating grounds. musca domestica captured from dairy cow barns and m. sorbens from defecating ground were found carrying more oocyst of cryptosporidi ...201119968842
investigations of the relationship between use of in vitro cell culture-quantitative pcr and a mouse-based bioassay for evaluating critical factors affecting the disinfection performance of pulsed uv light for treating cryptosporidium parvum oocysts in saline.cryptosporidium parvum is an enteric coccidian parasite that is recognised as a frequent cause of water-borne disease in humans. we report for the first time on use of the in vitro hct-8 cell culture-quantitative pcr (qpcr) assay and the in vivo scid-mouse bioassay for evaluating critical factors that reduce or eliminate infectivity of c. parvum after irradiating oocysts in saline solution under varying operational conditions with pulsed uv light. infections post uv treatments were detected by i ...201020096310
investigation of farms linked to human patients with cryptosporidiosis in england and wales.the study investigates farms suspected of being sources of zoonotic human cryptosporidiosis. a variety of implicated farm animal species were sampled and tested to detect cryptosporidium oocysts and investigate genetic linkage with human patients. risk factor information was collected from each farm and analysed by multivariable logistic regression to detect significant associations between factors and cryptosporidium in animals. the results showed that average sample prevalence of cryptosporidi ...201020096944
comparative efficacy of conventional primer sets in detection of cryptosporidium parvum for diagnostic use.in this study, the sensitivity and specificity of different previously described primer sets for cryptosporidium parvum detection by polymerase chain reaction (pcr) was evaluated. for this purpose, the primer sets defined by cacciò et al. (fems microbiol lett 170(1):173-179, 1999) (tub), widmer et al. (appl environ microbiol 64(11):4477-4481, 1998) (btub) and rochelle et al. (appl environ microbiol 63:2029-2037, 1997) (cphsp), respectively, were used. deoxyribonucleic acid (dna) was isolated fro ...201020107835
molecular characterisation of cryptosporidium isolates from swedish dairy cattle in relation to age, diarrhoea and region.cryptosporidium positive samples from 176 preweaned calves, young stock and cows of 48 herds were subjected to molecular characterisation of the 18s rrna gene to determine which species are present in swedish dairy cattle. in addition, samples characterised as cryptosporidium parvum were further analysed at the gp60 gene to investigate distribution and zoonotic potential of subtypes. the 18s rrna gene was successfully sequenced in 110 samples, with cryptosporidium bovis in 83, c. parvum in 15, c ...201020138705
first description of cryptosporidium bovis in japan and diagnosis and genotyping of cryptosporidium spp. in diarrheic pre-weaned calves in hokkaido.eighty fecal samples from pre-weaned calves with diarrhea were collected in the tokachi area in northern japan to investigate the prevalence of cryptosporidium species in such animals. oocysts from fecal samples collected from each animal were concentrated using sucrose gradient centrifugation. genomic dna was extracted from each sample and processed by nested pcr to amplify the partial ssu rrna gene of cryptosporidium. cryptosporidium infections were detected in 75% of the samples. sequence ana ...201020149546
single chain variable fragment antibodies selected by phage display against the sporozoite surface antigen s16 of cryptosporidium parvum.two human single chain variable fragment (scfv) libraries were used to select clones that bound to the surface glycoprotein s16 of cryptosporidium parvum. panning of the tomlinson libraries i and j resulted in the isolation of nine distinct clones. of the four clones which had full-length scfv, three contained stop codons. the remaining five clones were truncated, with four missing the heavy chain, and one missing most of the light chain. the full-length clones exhibited better binding to native ...201020093113
effect of tillage and rainfall on transport of manure-applied cryptosporidium parvum oocysts through soil.most waterborne outbreaks of cryptosporidiosis have been attributed to agricultural sources due to the high prevalence of cryptosporidium oocysts in animal wastes and manure spreading on farmlands. no-till, an effective conservation practice, often results in soil having higher water infiltration and percolation rates than conventional tillage. we treated six undisturbed no-till and six tilled soil blocks (30 by 30 by 30 cm) with 1 l liquid dairy manure containing 10(5) c. parvum oocysts per mil ...200919875795
molecular characterization and assessment of zoonotic transmission of cryptosporidium from dairy cattle in west bengal, india.few studies in the past have examined the genetic diversity and zoonotic potential of cryptosporidium in dairy cattle in india. to assess the importance of these animals as a source of human cryptosporidium infections, fecal samples from 180 calves, heifers and adults and 51 farm workers on two dairy farms in west bengal, india were genotyped by pcr-rflp analysis of the 18s rrna gene of cryptosporidium followed by dna sequencing of the pcr products. phylogenetic analysis was carried out on the d ...201020356678
genotype and subtype analysis of cryptosporidium isolates from calves and lambs in galicia (nw spain).faecal specimens from diarrhoeic pre-weaned calves (n=61) and lambs (n=127) collected over a 1-year period (2008-2009) at 27 cattle and 28 sheep farms in galicia (nw spain) were examined for the presence of cryptosporidium oocysts and positive specimens were selected for molecular examination. overall, 30 calves (49.2%) and 39 lambs (30.7%) tested positive for cryptosporidium by microscopy. pcr products of the ssu rrna locus were obtained for 27 cryptosporidium positive calf isolates and 23 lamb ...201020380767
seasonal variation in the prevalence and molecular epidemiology of cryptosporidium infection in dairy cattle in the new york city watershed.we conducted cross-sectional studies in the new york city watershed to ensure a valid estimate of the risk associated with cryptosporidium infection in dairy herds. our aims were to obtain species-specific estimates of the prevalence of cryptosporidium in dairy cattle and to investigate seasonal variations in prevalence. we validated our empirical estimates using a bayesian approach. samples were collected on 32 study farms, once in each of 3 different seasons using an age-stratified sampling de ...201020397026
temporal and spatial dynamics of cryptosporidium parvum infection on dairy farms in the new york city watershed: a cluster analysis based on crude and bayesian risk estimates.cryptosporidium parvum is one of the most important biological contaminants in drinking water that produces life threatening infection in people with compromised immune systems. dairy calves are thought to be the primary source of c. parvum contamination in watersheds. understanding the spatial and temporal variation in the risk of c. parvum infection in dairy cattle is essential for designing cost-effective watershed management strategies to protect drinking water sources. crude and bayesian se ...201020565805
effect of daily temperature fluctuation during the cool season on the infectivity of cryptosporidium parvum.the present work calculated the rate of inactivation of cryptosporidium parvum oocysts attributable to daily oscillations of low ambient temperatures. the relationship between air temperature and the internal temperature of bovine feces on commercial operations was measured, and three representative 24-h thermal regimens in the approximately 15 degrees c, approximately 25 degrees c, and approximately 35 degrees c ranges were chosen and emulated using a thermocycler. c. parvum oocysts suspended i ...201020023095
development of a visible-light-sensitized europium complex for time-resolved fluorometric application.the time-resolved luminescence bioassay technique using luminescent lanthanide complexes as labels is a highly sensitive and widely used bioassay method for clinical diagnostics and biotechnology. a major drawback of the current technique is that the luminescent lanthanide labels require uv excitation (typically less than 360 nm), which can damage living biological systems and is holding back further development of time-resolved luminescence instruments. herein we describe two approaches for pre ...201020151708
control of cryptosporidiosis in neonatal calves: use of halofuginone lactate in two different calf rearing systems.to date there is no effective treatment for bovine cryptosporidiosis. this study describes the use of halofuginone lactate in preventing cryptosporidiosis in naturally infected neonatal calves on a dairy farm with a high prevalence of infection. the animals were kept in two different calf rearing systems. a randomized double-blind trial was carried out with 32 naturally infected calves, divided into four groups. the two prophylactic halofuginone lactate treated groups were kept in either individ ...201020692058
seroprevalence of cryptosporidium parvum infection of dairy cows in three northern provinces of thailand determined by enzyme-linked immunosorbent assay using recombinant antigen cpp23.cryptosporidium parvum is the most frequent parasitic agent that causes diarrhoea in aids patients in thailand. cryptosporidiosis outbreaks in humans may be attributed to contamination of their drinking water from infected dairy pastures. a 23-kda glycoprotein of c. parvum (cpp23) is a sporozoite surface protein that is geographically conserved among c. parvum isolates. this glycoprotein is a potentially useful candidate antigen for the diagnosis of cryptosporidiosis by enzyme-linked immunosorbe ...200920698436
cryptosporidium infection in herds with and without calf diarrhoeal problems.a case-control study was designed to investigate the role of different cryptosporidium spp. in swedish dairy herds with and without calf diarrhoeal problems. faecal samples were collected from preweaned calves, young stock and cows. cryptosporidium oocysts were detected by sodium chloride flotation and epifluorescence microscopy. molecular diagnostics were used to identify cryptosporidium species. samples containing c. parvum were further analysed to determine subtypes. calf faecal samples were ...201020714750
survival of cryptosporidium parvum oocysts in the presence of hydrated lime.to investigate the effects of hydrated lime on the survival of cryptosporidium oocysts, the percentage viability of oocysts was assessed using fluorescent in situ hybridisation. in the absence of lime and with lime at a concentration of 1 per cent, there was a gradual decline in oocyst viability during the 10-day trial. although the addition of 5 or 10 per cent lime caused the total number of oocysts to decrease, there appeared to be an increase in the proportion of potentially viable oocysts.201020208077
the cpa135 gene as a marker to identify cryptosporidium species infecting humans.of the 22 species currently recognized as valid in the cryptosporidium genus, c. parvum and c. hominis account for most cases of human infections worldwide. however, c. meleagridis, c. canis, c. felis, c. suis, c. muris, as well as the cervine, rabbit and monkey cryptosporidium genotypes, have also been recognized as the etiologic cause of both sporadic and epidemic cryptosporidiosis in humans. molecular methods are necessary to distinguish species and genotypes of cryptosporidium, due to the la ...201020831899
development of a panel of multiplex real-time polymerase chain reaction assays for simultaneous detection of major agents causing calf diarrhea in feces.calf diarrhea is a major economic burden to the bovine industry. since multiple infectious agents can be involved in calf diarrhea, and the detection of each of the causative agents by traditional methods is laborious and expensive, a panel of 2 multiplex real-time polymerase chain reaction (pcr) assays was developed for rapid and simultaneous detection of the 5 major bovine enteric pathogens (i.e., bovine coronavirus [bcov; formally known as betacoronavirus 1], group a bovine rotavirus [brv], s ...201020622219
antibody responses following administration of a cryptosporidium parvum rcp15/60 vaccine to pregnant cattle.cryptosporidium parvum is a zoonotic apicomplexa-protozoan pathogen that causes gastroenteritis and diarrhea in mammals worldwide. globally, c. parvum is ubiquitous on dairy operations and is the pathogen most commonly diagnosed in association with calf diarrhea. here, we describe the antibody response in 20 pregnant cows to a recombinant c. parvum oocyst surface protein (rcp15/60) vaccine compared with 20 controls, and the antibody response in 19 calves fed the rcp15/60-immune colostrum from th ...201020951499
multilocus genetic analysis of cryptosporidium parvum from egypt.cryptosporidium parvum is a ubiquitous zonootic parasite causing enteritis in man and animals. cryptosporidium infection was confirmed microscopically in neonatal calves (less than 6 weeks of age) at kafr el sheikh province, egypt. multilocus analysis using a wide array of genetic markers was carried out to assess genetic diversity of c. parvum isolates. pcr amplification and partial sequence analysis of 70 kda heat shock protein, dihydrofolate reductase, alpha-tubulin, elongation factor 1 alpha ...201020625766
retrospective cohort study of an outbreak of cryptosporidiosis caused by a rare cryptosporidium parvum subgenotype.summarythe occurrence of a gastrointestinal illness among a class of 96 undergraduate veterinary students in new zealand prompted laboratory and questionnaire-based investigations. cryptosporidium parvum was the only enteropathogen identified in 4/7 faecal specimens analysed. the c. parvum isolates carried a rare iia gp60 allele, indicating a point-source outbreak. the infection source could not be microbiologically traced, but the investigation suggested contact with calves during a practical c ...201021087535
quantitative risk assessment for zoonotic transmission of cryptosporidium parvum infection attributable to recreational use of farmland.summary cryptosporidiosis caused by cryptosporidium parvum infection is a major cause of enteric illness in man and there is a significant reservoir in animals, particularly young ruminant species. to preliminary assess the magnitude of the risk posed by contact with faeces produced by infected livestock, two microbiological risk assessments have been developed: one for the risk of human infection with c. parvum while camping on contaminated land recently grazed by infected suckler cattle and a ...201020726959
molecular characterization of cryptosporidium spp. in pre-weaned dairy calves in the czech republic: absence of c. ryanae and management-associated distribution of c. andersoni, c. bovis and c. parvum subtypes.a total of 750 faecal samples of dairy calves at up to 2 months of age kept in various housing systems were screened for cryptosporidium spp. infection using the aniline-carbol-methyl violet staining method. dna was extracted from cryptosporidium positive samples and from 150 randomly selected microscopically negative samples. nested pcr was performed to amplify the partial ssu rrna gene of cryptosporidium that was subsequently digested by sspi, vspi and mboii restriction enzymes to determine th ...201021168973
characteristics of cryptosporidium transmission in preweaned dairy cattle in henan, china.to estimate the prevalence and public health significance of cryptosporidiosis in preweaned calves in china, 801 fecal samples from eight farms in seven areas in henan province were examined for cryptosporidium oocysts. the overall infection rate of cryptosporidium was 21.5%, with the farm in xinxiang having the highest prevalence (40%). no significant difference in infection rates was observed between seasons. cryptosporidium spp. were characterized by pcr-restriction fragment length polymorphi ...201021177898
zoonotic cryptosporidiosis from petting farms, england and wales, 1992-2009. 201121192888
quantitative comparison of different purification and detection methods for cryptosporidium parvum oocysts.cryptosporidium parvum (c. parvum) is the causal agent of cryptosporidiosis in many animals, mainly cattle, and possesses a high zoonotic potential. it occurs worldwide and ubiquitously. detection of c. parvum is mainly performed directly but purification of the oocysts is useful to increase sensitivity and to obtain oocyst material for further use. the study was designed to compare (a) three different direct diagnostic methods, namely modified ziehl-neelsen staining, carbol fuchsin staining and ...201021242035
molecular and phylogenetic analyses of cryptosporidium spp from dairy cattle in egypt.cryptosporidium infections in cattle result in considerable'economic loss as well as a significant source for zoonotic infection. this study was devoted to spot analysis on cryptosporidium parasites derived from dairy cattle at kafr el sheikh province, egypt, using morphological and molecular tools. fecal specimens from neonatal calves as well as adult cattle were screened for cryptosporidium oocysts using modified ziehl-neelsen technique. oocysts in positive samples were concentrated using suga ...201021246942
molecular characterization of cryptosporidium spp. in native breeds of cattle in kaduna state, nigeria.despite numerous molecular epidemiologic studies of cryptosporidiosis in dairy cattle in industrialized countries, there are very few studies on the diversity and public health significance of cryptosporidium species in native cattle in developing countries. in this study, a polymerase chain reaction (pcr)-restriction fragment length polymorphism (rflp) analysis of the small-subunit (ssu) rrna gene was used to detect and identify cryptosporidium spp. in 194 fecal specimens from 2 to 365 days old ...201121277091
genotyping of cryptosporidium parvum isolates in bovine population in kolkata and characterization of new bovine genotypes.cryptosporidium infection may have adverse effect in health and production potential of cattle herd. the exact profile of cryptosporidium infection in bovine population of india in general, particularly from kolkata is scarce. we here report systematic investigation of clinical and genetic profiling of promiscuous cryptosporidium infection in selected representative cattle farms from kolkata as well as some surrounding local areas. the current study was conducted in the period of october to sept ...201121316723
quantitative real time polymerase chain reaction assays for the sensitive detection of besnoitia besnoiti infection in cattle.bovine besnoitiosis, an economically important disease in cattle in some countries of africa and asia, is emerging in europe. the definitive host of besnoitia besnoiti, the causative agent of bovine besnoitiosis, is unknown and the transmission of the parasite is not completely understood. sensitive and quantitative dna detection methods are needed to determine whether serologically positive animals are infectious and to examine the role of vectors (e.g. haematophagous insects) in the transmissi ...201121324596
[laboratory-based evaluation of loop-mediated isothermal amplification (lamp) to detect cryptosporidium oocyst and giardia lamblia cyst in stool specimens].to establish an alternative and more sensitive test method to detect oocyst of cryptosporidium parvum and cyst of giardia lamblia in clinical stool specimens, loop-mediated isothermal amplification (lamp) was evaluated. minimum cell concentrations at which lamp assay could detect c. parvum oocyst and g. lamblia cyst were determined as 6.25 x 10(-1) and 3.12 x 10(-1) cells/assay when the stool specimens were spiked with the respective parasites. the results indicated 400 times higher sensitivitie ...201020860168
the potential for zoonotic transmission of giardia duodenalis and cryptosporidium spp. from beef and dairy cattle in ontario, canada.the objective of this study was to compare the occurrence and the genotypes and species of giardia duodenalis and cryptosporidium spp. in beef and dairy cattle from farms in the regional municipality of waterloo, ontario, in an effort to determine the potential for zoonotic transmission from these animals. pooled manure samples were collected from 45 dairy cattle farms and 30 beef cattle farms. the presence of giardia cysts and cryptosporidium oocysts was determined by immunofluorescence microsc ...201020971563
gene expression during excystation of cryptosporidium parvum oocysts.the present study describes transcription of mrna from genes encoding metabolic or structural proteins during excystation of cryptosporidium parvum oocysts. rna was harvested from c. parvum oocysts before excystation, and at 5, 10, and 15 min during excystation. subtractive cdna libraries were prepared by using mrna from non-excysted c. parvum oocysts to "subtract out" mrna from excysting oocysts. the "subtracted" cdna was used to prepare libraries enriched for transcripts possibly involved in e ...201121380575
a recombinant dna vaccine encoding c. andersoni oocyst wall protein induces immunity against experimental c. parvum infection.cryptosporidium andersoni parasited in the abomasum has been demonstrated as a cause of reduction of milk production in dairy cow. in this study, a novel chimeric dna vaccine pvax1-ab was constructed and the efficacy against cryptosporidium parvum was determined. balb/c mice were divided into 3 groups and immunized with dna vaccine expressing the oocyst wall protein, ab protein of c. andersoni, the recombinant plasmid containing the ab gene, respectively. after inoculation of 1 × 10(6) oocysts o ...201121450406
cryptosporidium parvum in diarrheic calves detected by microscopy and identified by immunochromatographic and molecular methods.cryptosporidium is an important protozoan parasite that causes diarrhea in neonates and young bovines. the objective of the present study was to determine the frequency of cryptosporidium infection in animals of dairy farms of the metropolitan region (santiago), chile. fecal samples of 205 newborn calves with diarrhea were studied and used for comparing the efficiency of two microscopic staining methods for diagnosis of the parasite, the auramine (au) and a modified ziehl-neelsen (zn) procedure. ...201021109352
a comparison of fecal percent dry matter and number of cryptosporidium parvum oocysts shed to observational fecal consistency scoring in dairy calves.abstract evaluation of dairy calf feces is often used in research and for clinical decision making to assess severity of diarrhea. however, this has not been validated for agreement between dry matter content and observed fecal consistency. therefore, a comparison of observed fecal consistency score to fecal percent dry matter and cryptosporidium parvum oocyst shedding was performed to assess the accuracy of observational scoring as a measure of diarrhea and its association with number of oocyst ...201121506794
detection and differentiation of coccidian oocysts by real-time pcr and melting curve analysis.abstract rapid and reliable detection and identification of coccidian oocysts are essential for animal health and food-borne disease outbreak investigations. traditional microscopy and morphological techniques can identify large and unique oocysts, but are often subjective and require parasitological expertise. the objective of this study was to develop a real-time quantitative pcr (qpcr) assay with melting curve analysis (mca) to detect, differentiate, and identify dna from coccidian species of ...201121506835
efficacy of halofuginone lactate in the prevention of cryptosporidiosis in dairy calves.to evaluate the efficacy of halofuginone lactate (halocur; intervet) when used prophylactically against cryptosporidiosis in dairy calves, 513 holstein heifer calves were randomly distributed between two experimental groups. those in the treatment group (n=259) received 0.1 mg halofuginone base per kg bodyweight daily in a 10 ml solution, for the first seven days following birth, while those in the control group (n=254) received an equal volume of a placebo solution. faecal samples were collecte ...201121546409
subtype analysis of cryptosporidium parvum and cryptosporidium hominis isolates from humans and cattle in iran.cryptosporidium is an intestinal parasite associated with severe acute diarrhea in humans and animals. to investigate subtypes of cryptosporidium spp. isolated from humans and cattle in iran, 47 cryptosporidium parvum (22 from children and 25 from cattle) and three cryptosporidium hominis from children were characterized by sequence analysis of the 60 kda glycoprotein (gp60) gene. nine subtypes (two of c. hominis and seven of c. parvum) in four subtype families were identified. cattle were mainl ...201121376469
molecular characterisation of cryptosporidium isolates from pre-weaned calves in romania: is there an actual risk of zoonotic infections?diarrheic fecal samples from 258 pre-weaned calves (1-30 day-old) from 9 dairy farms located in banat region, romania, were microscopically examined for the presence of cryptosporidium oocysts. overall, 65 (25%) samples were found positive. a higher percent of infection was recorded in calves aged between 8 and 14 days compared with other age categories (1-7, 8-14, 15-21 and 22-30 days; p<0.05). genetic characterization was carried out on all cryptosporidium-positive samples. after dna extractio ...201121612871
a whole water catchment approach to investigating the origin and distribution of cryptosporidium species.aims:  investigating the distribution and origin of cryptosporidium species in a water catchment affected by destocking and restocking of livestock due to a foot and mouth disease epidemic. methods and results:  surface water, livestock and wildlife samples were screened for cryptosporidium and oocysts characterised by sequencing ssu rrna and cowp loci, and fragment analysis of ml1, ml2 and gp60 microsatellite loci. oocyst concentrations in water samples (0 to 20.29 per 10l) were related to rain ...201121649804
prevalence of major enteric pathogens in australian dairy calves with diarrhoea.determine the prevalence of the major enteric pathogens in dairy and dairy beef calves with diarrhoea in australia.201121495987
cryptosporidium infection in non-human hosts in malawi.of 1346 faecal samples from the chikwawa and thyolo districts of malawi, analysed for the presence of cryptosporidium oocysts between october 2001 and may 2003, 61.3% were from cattle (29.8% of these were from calves <6 months old). cryptosporidium oocysts were detected during all three seasons studied in chikwawa and thyolo. in chikwawa, 13.6% of adult cattle and 11.7% of calves were infected, compared to 28.9% of adult cattle and 36.7% of calves in thyolo. dependent on season, between 7.8% and ...200921344786
cryptosporidiosis outbreak at a summer camp --- north carolina, 2009.in july 2009, local, regional, state, and federal public health officials investigated a cryptosporidiosis outbreak at a youth summer camp in north carolina. the investigation identified 46 laboratory-confirmed and probable cryptosporidiosis cases at the camp. analyses of data from a retrospective cohort study of staff members revealed that eating ham from a sandwich bar that included camp-grown raw produce and sharing a cabin with an ill person were significantly associated with illness. crypto ...201121753745
fluorescence analysis detects gp60 subtype diversity in cryptosporidium infections.ninety percent of human cryptosporidiosis infections are attributed to two species; the anthroponotic cryptosporidium hominis and the zoonotic cryptosporidium parvum. sequence analysis of the hypervariable gp60 gene, which is used to classify cryptosporidium to the subtype level, has highlighted extensive intra-species diversity within both c. hominis and c. parvum. the gp60 has also facilitated contamination source tracking and increased understanding of the epidemiology of cryptosporidiosis. t ...201121609784
the loading of labelled antibody-engineered nanoparticles with indinavir increases its in vitro efficacy against cryptosporidium parvum.summarythere is much evidence to indicate the ability of indinavir (ind) to reduce cryptosporidium parvum infection in both in vitro and in vivo models. however, there are limitations to the administration of ind as such, due to its renal toxicity and the high rate of metabolism and degradation. we aimed to encapsulate ind in biodegradable poly (d,l-lactide-co-glycolide) nanoparticles (np) and to engineer their surface by conjugation with an anti-cryptosporidium igg polyclonal antibody (ab). tet ...201121819637
selection and identification of a new adhesion protein of cryptosporidium parvum from a cdna library by ribosome display.in this study, we described a novel display method to identify surface adhesion proteins of cryptosporidium parvum. a cdna library of the sporozoite and oocyst stages of c. parvum was expressed on ribosome and selectively and specifically screened with intestinal epithelial cells (iecs) from newborn cryptosporidium-free holstein calves. proteins were then enriched using a multi-step panning procedure. a new surface adherence protein of c. parvum was selected, named cp20. sequence analyses showed ...201121740903
multilocus fragment typing and genetic structure of cryptosporidium parvum isolates from diarrheic preweaned calves in spain.a collection of 140 cryptosporidium parvum isolates previously analyzed by pcr-restriction fragment length polymorphism (pcr-rflp) and sequence analyses of the small-subunit (ssu) rrna and 60-kda glycoprotein (gp60) genes was further characterized by multilocus fragment typing of six minisatellite (msb and ms5) and microsatellite (ml1, ml2, tp14, and 5b12) loci. isolates were collected from diarrheic preweaned calves originating from 61 dairy cattle farms in northern spain. a capillary electroph ...201121908632
detection of viable cryptosporidium parvum in soil by reverse transcription real time pcr targeting hsp70 mrna.extraction of high-quality mrna from cryptosporidium parvum is a key step in pcr detection of viable oocysts in environmental samples. current methods for monitoring oocysts are limited to water samples; therefore, the goal of this study was to develop a rapid and sensitive procedure for cryptosporidium detection in soil samples. the effectiveness of five rna extraction methods were compared (mrna extraction with the dynabeads® mrna direct™ kit after chemical and physical sample treatments, and ...201121803904
[Development of multiplex microbead immunoassay for detection of specific antibodies against Cryptosporidium parvum].To develop a multiplex microbead immunoassay for detection of specific antibodies against Cryptosporidium parvum using recombinant proteins CP23, SA35 and SA40.201122164624
detection of faecal cryptosporidium parvum antigen in diarrheic holstein dairy cows.over a one-year period, based on a random cluster sampling design, 661 faecal samples from natural cases of diarrheic calves were taken in fars province of iran. the samples were taken from the 267 diarrheic calves of high and 394 diarrheic calves of average producing holstein dairy cows. faecal samples were collected directly from the rectum. herd selection was based on geographical location and density of cattle in the region. samples were collected based on 5 percent of herd populat ...201122041760
assessment of three methods for multilocus fragment typing of cryptosporidium parvum from domestic ruminants in north west spain.the performance of three different methods, capillary electrophoresis (ce), high resolution slab-gel electrophoresis and sequencing, for pcr fragment size analysis of two cryptosporidium parvum microsatellite regions, ml1 and ml2, was investigated by analysing 27 isolates from calves and 14 from lambs. to assess genetic variability of this protozoan in domestic ruminants in north west spain, results were combined with sequence analysis of the 60kda glycoprotein (gp60) gene creating a multilocus ...201122154970
phospholipases and cationic peptides inhibit cryptosporidium parvum sporozoite infectivity by parasiticidal and non-parasiticidal mechanisms.abstract cryptosporidium parvum is an important cause of diarrhea in humans and cattle and can persistently infect immunocompromised hosts. no consistently effective parasite-specific pharmaceuticals or immunotherapies for control of cryptosporidiosis are presently available. the innate immune system represents the first line of host defense against a range of infectious agents, including parasitic protozoa. a variety of antimicrobial peptides and proteins, collectively referred to herein as bio ...201121787211
effect of dung burial by the dung beetle bubas bison on numbers and viability of cryptosporidium oocysts in cattle dung.cryptosporidium oocysts were inoculated into fresh dung (~1.2×10(4) oocysts per gram wet weight) and fed to dung beetles to assess the effect of dung burial by the dung beetle bubas bison on the distribution of the oocysts in small cores of soil in the laboratory. the experiment consisted of five replicates of each of two treatments; controls (dung but no dung beetles) and the experimental treatment (inoculated dung and seven pairs of dung beetles). after 5 days, when approximately 90% of the du ...201121745472
cryptosporidium tyzzeri and cryptosporidium pestis: which name is valid? 201222230707
prevalence and molecular characterization of cryptosporidium spp. and giardia duodenalis in dairy cattle in beijing, china.822 fecal samples from cattle in six areas of beijing were examined with microscopy for cryptosporidium oocysts and giardia cysts. the overall infection rates for cryptosporidium spp. and giardia duodenalis were 2.55% and 1.09%, respectively. cryptosporidium was only detected in calves and heifers, whereas g. duodenalis was found in all age groups. cryptosporidium spp. were characterized with a pcr-restriction fragment length polymorphism analysis and dna sequence analysis of the small subunit ( ...201626921041
prevalence and molecular characterization of cryptosporidium spp. in dairy cattle, northwest china.cryptosporidium spp. cause enteric diseases in a wide range of animals, including dairy cattle. however, limited information is available regarding prevalence and molecular characterization of cryptosporidium spp. in dairy cattle in gansu province and ningxia hui autonomous region (nxhar), northwest china. a total of 2945 dairy feces samples (1257 from gansu province and 1688 from nxhar) were collected between december 2012 and march 2014 and were tested by pcr amplification of the small subunit ...201526002827
prevalence and molecular typing of cryptosporidium in dairy cattle in england and wales and examination of potential on-farm transmission routes.an average of 70 samples were collected from 80 dairy farms in england and wales, from cattle, co-grazed sheep, wildlife and farm wastes, to investigate prevalence, potential sources and transmission routes of cryptosporidium. at least one positive sample was detected on 74 of the farms (92.5%) by ifat microscopy. the prevalence in cattle was 10.2% (95% ci 9.4-11.1%), with greater prevalences detected in calf samples, especially from those under 1 month (45.1%). young calves were also more likel ...201424909077
prevalence and characterization of cryptosporidium spp. in dairy cattle in nile river delta provinces, egypt.molecular characterizations of cryptosporidium spp. in dairy cattle in industrialized nations have mostly shown a dominance of cryptosporidium parvum, especially its iia subtypes in pre-weaned calves. few studies, however, have been conducted on the distribution of cryptosporidium species and c. parvum subtypes in various age groups of dairy cattle in developing countries. in this study, we examined the prevalence and molecular characteristics of cryptosporidium in dairy cattle in four nile rive ...201324036320
molecular characterization of cryptosporidium isolates from high-excreting young dairy calves in dairy cattle herds in western france.ninety-two cryptosporidium sp.-positive fecal samples of dairy diarrheic or non-diarrheic calves from 30 cattle herds in normandy (france) were selected. here, the aim was to investigate the species of cryptosporidium excreted as well as the subtypes of cryptosporidium parvum found in 7-17-day-old dairy calves. excretion levels were comprised between 2 × 10(4) and 4 × 10(7) oocysts per gram of feces. here, a nested 18s ssu rrna pcr associated with sequencing was performed for identification of c ...201323820609
report of fatal mixed infection with cryptosporidium parvum and giardia intestinalis in neonatal calves.in the production and management of beef and dairy cattle, controlling diarrhea is one of the important concerns. pathogenic agents of the disease, protozoan parasites including cryptosporidium spp., are difficult to control, making prevention, diagnoses, and treatment of diarrhea. in the present study, we investigated a farm with a history of calf deaths over a period of 10 years in order to determine the cause of disease and to clarify the detailed distribution of the pathogens. in four examin ...201728030344
cross sectional study of prevalence, genetic diversity and zoonotic potential of cryptosporidium parvum cycling in new zealand dairy farms.the estimation of the prevalence and zoonotic potential of cryptosporidium parvum cycling in bovine populations requires the use of genotyping, as several morphologically similar non-parvum genetic variants of unproven clinical and public health impact are found in cattle. however, robust c. parvum prevalence estimates in cattle are lacking and comparative data of bovine and human isolates collected from the same regions are scarce. thus, the relative contribution of the c. parvum oocysts releas ...201525896433
cryptosporidiosis caused by cryptosporidium parvum subtype iida15g1 at a dairy farm in northwestern china.cryptosporidium spp. are zoonotic parasites responsible for diarrhoeal diseases in animals and humans worldwide. cattle are the most common mammalian species in which cryptosporidium is detected, with pre-weaned calves considered to be reservoirs for zoonotic c. parvum. in october 2013, severe diarrhoea was observed in 396 pre-weaned calves at a farm in the ningxia autonomous region of northwestern china. 356 of the infected calves died despite antibiotic therapy.201425430474
[development of an ims-qpcr method for detection of cryptosporidium parvum in water].to develop a detection method for cryptosporidium parvum oocysts from water samples, which combined immunomagnetic separation (ims) with taqman real-time pcr (qpcr).201324812853
cryptosporidium parvum gp60 subtypes in dairy cattle from buenos aires, argentina.cryptosporidium parvum from 73 dairy calves less than two months old from buenos aires province (argentina) were molecularly characterized using sequence analysis of the gp60 gene. seventy-five sequences were obtained, and seven different subtypes were identified, all belonging to the iia subtype family. the most common subtypes were iiaa20g1r1 (27/75), iiaa22g1r1 (16/75), and iiaa18g1r1 (13/75). subtypes iiaa21g1r1, iiaa23g1r1, iiaa16g1r1 and iiaa19g1r1 were found sporadically. two samples cont ...201424480390
population genetic characterisation of dominant cryptosporidium parvum subtype iiaa15g2r1.the subtype iiaa15g2r1 at the 60 kda glycoprotein (gp60) gene locus is the most dominant cryptosporidium parvum infecting dairy cattle and humans in industrialised nations. the reasons for its high transmissibility are not clear, and it remains to be determined whether this subtype represents a homogeneous parasite population. in this study, we sequence-characterised 26 iiaa15g2r subtype specimens and 26 non-iiaa15g2r subtype specimens from the united states, canada, united kingdom and spain at ...201324126186
prevalence and molecular identification of cryptosporidium spp. in pre-weaned dairy calves in mashhad area, khorasan razavi province, iran.cryptosporidium parvum is a zoonotic pathogen transmissible from a variety of animals to humans and is a considerable public health concern. dairy cattle have been identified in numerous reports as a major source of environmental contamination with this pathogen. the aim of study was to detect and isolate the cryptosporidium spp. from fecal samples of naturally infected pre-wean calves in the mashhad area.201325516742
peri-parturient rise of cryptosporidium oocysts in cows: new insights provided by duplex quantitative real-time pcr.in order to clarify if a peri-parturient rise of cryptosporidium parvum oocysts occurs in cows, faecal samples from 42 cows on two farms were collected. these samples were taken during the pre-parturient, the peri-parturient and the post-parturient periods. two methods were used to detect the oocysts, a nested-pcr coupled with sequencing and a duplex real-time pcr (qpcr) that quantified cryptosporidium spp. dna concentration. the qpcr results were adjusted using a hierarchical bayesian model tak ...201222681972
microbiological quality indicators in waters of dairy farms: detection of pathogens by pcr in real time.when contaminated water is used to wash the udders of dairy cattle and milking utensils, raw milk may become contaminated with pathogens. washing with high quality water is essential to reduce the microbial contamination of milk. furthermore, the wastewater generated in dairy herds also contains high populations of pathogens, antibiotics and nutrients that more often are thrown into the water bodies without any treatment. in this work, both supply water and wastewater from 20 dairy farms from an ...201222542296
real-time pcr assay targeting the actin gene for the detection of cryptosporidium parvum in calf fecal samples.cryptosporidium parvum infection is very important with respect to public health, owing to foodborne and waterborne outbreaks and gastrointestinal illness in immunocompetent and immunocompromised persons. in cattle, infection with this species manifests either as a subclinical disease or with diarrheal illness, which occurs more often in the presence of other infectious agents than when alone. the aim of this study was to develop a real-time polymerase chain reaction (pcr) assay for the detectio ...201122042503
occurrence of cryptosporidium and giardia on beef farms and water sources within the vicinity of the farms on prince edward island, canada.the objectives of this study were to determine the prevalence and assemblages of giardia and species of cryptosporidium on beef farms in prince edward island (pei), canada, including the water sources associated with the farms, and to determine risk factors for infection of cattle with these parasites. twenty beef farms were selected based on the presence of surface water<500m from the barn. prevalence was determined by direct immunofluorescence microscopy, while genotyping and species determina ...201122112978
Evaluation of factors associated with the risk of infection with Cryptosporidium parvum in dairy calves.Objective-To identify risk factors associated with Cryptosporidium parvum infection in dairy calves. Animals-108 case animals and 283 control animals. Procedures-Case animals were calves infected with C parvum, and controls were infected with Cryptosporidium bovis (n = 67) or calves not infected with Cryptosporidium spp. Fecal samples were tested via the flotation concentration method for Cryptosporidium spp. Samples were genotyped by sequencing of the 18s rRNA gene. Associations between hos ...201222204291
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