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sample prevalence and molecular characterisation of cryptosporidium andersoni within a dairy herd in the united kingdom.bovine cryptosporidiosis is usually an acute diarrhoeal disease of young calves caused by cryptosporidium parvum. however, chronic infection with cryptosporidium andersoni has been associated with gastritis, reduced milk yield and poor weight gain in adult cattle. here we describe the first genetic confirmation and characterisation of c. andersoni from cattle in the united kingdom and its sample prevalence within a dairy herd. oocysts measured 7.5+/-0.4 microm x 5.5+/-0.4 microm (7.0-8.5 microm ...200616908101
evidence supporting zoonotic transmission of cryptosporidium spp. in wisconsin.cryptosporidium hominis and cryptosporidium parvum are the primary species of cryptosporidium that infect humans. c. hominis has an anthroponotic transmission cycle, while c. parvum is zoonotic, infecting cattle and other ruminants, in addition to humans. most cryptosporidiosis outbreaks in the united states have been caused by c. hominis, and this species is often reported as the primary cause of cryptosporidiosis in this country. however, outbreaks account for only 10% of the overall cryptospo ...200617005736
[study on methods for isolation and purification of cryptosporidium parvum oocysts from mouse feces].to explore an applicable method for isolation and purification of cryptosporidium parvum oocysts with high purity, recovery and vigor from mouse feces.200617094628
zoonotic cryptosporidiosis in man and animal in farms, giza governorate, egypt.to demonstrated the zoonotic cryptosporidiosis. a total of 189 farmers and their farm animals (200= 71 buffaloes, 59 cows, 43 sheep and 27 goats were examined. stool samples each stool sample was subjected to the direct wet smear method and sheather's sugar flotation and acid-ether sedimentation techniques and stained with four stains (modified ziehl neelsen, safranin, methylene blue, aniline carbol methyl violet and giemsa). a positive statistically significant correlation was observed between ...200617366871
giardiasis and cryptosporidiosis in ruminants.although they differ considerably with respect to their biology, both giardia duodenalis and cryptosporidium parvum are common in ruminants, whereas cryptosporidium andersoni is not. g. duodenalis infections are acquired during the first few months of life, tend to be chronic, and may be a production-limiting disease of ruminants. c. parvum infections remain an important cause of diarrhea in neonatal ruminants. abomasal cryptosporidiosis, caused by c. andersoni, is an emerging disease of cattle ...200617071357
interaction of cryptosporidium hominis and cryptosporidium parvum with primary human and bovine intestinal cells.cryptosporidiosis in humans is caused by the zoonotic pathogen cryptosporidium parvum and the anthroponotic pathogen cryptosporidium hominis. to what extent the recently recognized c. hominis species differs from c. parvum is unknown. in this study we compared the mechanisms of c. parvum and c. hominis invasion using a primary cell model of infection. cultured primary bovine and human epithelial intestinal cells were infected with c. parvum or c. hominis. the effects of the carbohydrate lectin g ...200616368962
persistent infection in a dairy herd with an unusual genotype of bovine cryptosporidium parvum.on two occasions, we identified cryptosporidium parvum with an unusual banding pattern after restriction enzyme digestion of cryptosporidium oocyst wall protein pcr fragments. the samples originated from a single farm with calf diarrhoea. the cryptosporidium oocyst wall protein pcr fragment sequence revealed a point mutation in one of the recognition sites for rsai. our subgenotyping showed that samples from both samplings shared the same ms1 and gp15 alleles. analysis of the tp14 microsatellite ...200616451181
recombinant bovine interleukin-12 stimulates a gut immune response but does not provide resistance to cryptosporidium parvum infection in neonatal calves.this study was undertaken to determine if administration of recombinant bovine interleukin-12 (rboil-12) could stimulate a cellular immune response that protected calves from an oral challenge inoculation with cryptosporidium parvum oocysts. in a first experiment, rboil-12 intraperitoneally administered as a single dose 1 day before challenge inoculation, did not alter the course of infection. the percentage of immune competent cells and levels of cytokine gene expression in the ileo-cecal mucos ...200616386849
changes of physical and biochemical properties of cryptosporidium oocysts with various storage conditions.physical and biochemical properties of cryptosporidium parvum oocyst were examined after storage under various conditions. oocyst-positive-fecal samples recovered from calves were either stored in a 2.0% potassium dichromate solution (cr) or deionized water (w), or kept as a fecal pellet (p), and stored at 4 or 18 degrees c for a maximum of 100 days. when stored in cr at 4 degrees c, the morphology of oocysts and their ability to withstand ultrasonics was not affected by the storing media or the ...200616458949
environmental load of cryptosporidium parvum oocysts from cattle manure in feedlots from the central and western united states.the first step in assessing the risk of water contamination by cryptosporidium parvum oocysts from feedlot cattle (bos taurus) production systems is to quantify the number of c. parvum oocysts present in the fecal material deposited by feedlot cattle. our primary objective for this project was to estimate the daily environmental load of c. parvum oocysts in fecal material deposited by feedlot cattle from across the central and western usa. our secondary goal was to genotype isolates of c. parvum ...200616391291
prevalence and genotyping of cryptosporidium in three cattle husbandry systems in zambia.to estimate the prevalence of cryptosporidium spp. in three different husbandry systems in zambia, faecal samples were collected from calves up to the age of 3 months. faecal consistency was scored for correlation with infection. additionally, 45 positive samples were selected for genotyping by amplification of the 70-kda heat shock protein (hsp-70) and the 18s rrna gene. a total of 37 dairy, 25 beef and 92 traditional husbandry farms were visited: 250 samples were collected on dairy farms, 238 ...200616546321
genotype and subtype analyses of cryptosporidium isolates from dairy calves and humans in ontario.to assess the importance of dairy cattle as a source of human cryptosporidium infections in ontario, canada, 44 cryptosporidium isolates from neonatal dairy calves and 11 from sporadic human cases of cryptosporidiosis in the province were genotyped by pcr-rflp analyses of the cryptosporidium oocyst wall protein (cowp) and 18s rrna genes. isolates were also subtyped by sequence analysis of the 60-kda glycoprotein (gp60) gene. all bovine isolates successfully subtyped belonged to cryptosporidium p ...200616565813
emergence of distinct genotypes of cryptosporidium parvum in structured host populations.cryptosporidium parvum is an apicomplexan parasite that infects humans and ruminants. c. parvum isolated from cattle in northeastern turkey and in israel was genotyped using multiple polymorphic genetic markers, and the two populations were compared to assess the effect of cattle husbandry on the parasite's population structure. dairy herds in israel are permanently confined with essentially no opportunity for direct herd-to-herd transmission, whereas in turkey there are more opportunities for t ...200616597950
cryptosporidium parvum: treatment effects and the rate of decline in oocyst infectivity.cryptosporidium parvum has become the focus of numerous studies on waterborne disease and transmission in response to outbreaks endangering populations worldwide. the foci detection method-most probable number assay (fdm-mpn) is an in vitro cell culture method that has been developed and used to determine the quantity of infectious c. parvum oocysts. this research evaluated 2 vendor's producing oocysts, sterling parasitology laboratory (spl) and pleasant hill farms (phf) (now known as bunch gras ...200616629316
quantitative tracking of cryptosporidium infection in cell culture with cfse.immunofluorescence-based assays have been developed to detect and quantitate cryptosporidium parvum infection in cell culture. here, we describe a method that tracks and quantifies the early phase of attachment and invasion of c. parvum sporozoites using a fluorescent dye. newly excysted sporozoites were labeled with the amine-reactive fluorescein probe carboxyfluorescein diacetate succinimidyl esters (cfse) using an optimized protocol. the initial invasion of cells by labeled parasites was dete ...200617304819
prevalence of cryptosporidium parvum infection in punjab (india) and its association with diarrhea in neonatal dairy calves.a prevalence study was contemplated to determine the prevalence of cryptosporidium spp. in dairy farms in punjab, india. the cryptosporidium oocysts were detected from 50 and 25.68% from 80 diarrheic and 74 non-diarrheic animals, respectively. both shedding and intensity of shedding were significant in calves with diarrhea. the cryptosporidium spp. appears to be common in dairy calves and an important contributor of calf diarrhea in the punjab province. the prevalence of the infection peaked in ...200616647820
characterization of a factor from bovine intestine that protects against cryptosporidium parvum infection.cryptosporidium parvum is a protozoan parasite that causes intestinal infection in a variety of mammals. we have previously described a factor in adult rat or adult bovine intestinal mucosa that protects against c. parvum infection when fed to susceptible infant rats. this factor is absent in intestinal mucosa from bovine calves. in the present study we describe the further characterization of the active component of bovine intestinal mucosa. the ability to protect infant rats against c. parvum ...200616870345
factors associated with shedding of cryptosporidium parvum versus cryptosporidium bovis among dairy cattle in new york state.to isolate and speciate cryptosporidium dna from fecal samples obtained from dairy cattle in new york state and identify factors associated with whether cattle were shedding cryptosporidium parvum versus cryptosporidium bovis.200617107320
prevalence of cryptosporidium parvum in mithuns (bos frontalis) from india.systematic examination of faecal samples from mithuns maintained at the national research centre on mithun, indian council of agricultural research (icar), nagaland, india and mithuns found in free-ranging condition of nagaland, by using a commercially available enzyme-linked immunosorbent assay kit, revealed that the overall prevalence of cryptosporidium parvum in mithun was 56% (95% ci=48-64). highest (prevalence rate=81, 95% ci=67-95) prevalence was found in mithuns of 1-6 months of age and l ...200616876325
quantitative and qualitative comparisons of cryptosporidium faecal purification procedures for the isolation of oocysts suitable for proteomic analysis.with the recent publication of the cryptosporidium genome, investigation of the proteins expressed by cryptosporidium parvum will provide complementary information on the biology of this complex organism. proteomic studies on this apicomplexan parasite have been hampered due to the inability to culture or isolate high numbers required for 2d gel analysis. neonatal calves are a common source of cryptosporidium oocysts and we report on the development of a sucrose-percoll purification procedure wh ...200616696982
failure to propagate cryptosporidium spp. in cell-free culture.the successful propagation of cryptosporidium parvum in cell-free culture medium was recently reported. to investigate whether this phenomenon could be broadened to include other c. parvum isolates, as well as cryptosporidium hominis, we attempted to propagate 3 isolates in cell-free medium under reported culture conditions. cryptosporidium oocysts from c. parvum strains moredun (md) or iowa or c. hominis strain tu502 were added to media containing coagulated newborn calf serum. the cultures wer ...200616729703
an improved electron microscopic technique for the immunolabeling of cryptosporidium parvum oocysts.a technique was developed for immunolabeling cryptosporidium parvum oocysts for subsequent observation by transmission electron microscopy. this method was developed to maintain architectural integrity of the oocyst wall and improve fixation of internal contents. the improved fixation and embedding method permits efficient immunolabeling of both nonexcysted and excysted c. parvum oocysts and may be applicable to other oocyst- and cyst-forming protozoa.200616729705
bile acids enhance invasiveness of cryptosporidium spp. into cultured cells.bile salts such as sodium taurocholate (natc) are routinely used to induce the excystation of cryptosporidium oocysts. here we show that natc significantly enhanced the invasion of several cultured cell lines by freshly excysted cryptosporidium parvum and cryptosporidium hominis sporozoites. a variety of purified bile salts or total bile from bovine also enhanced the invasion of cultured cells by c. parvum. further studies demonstrated that natc increased protein secretion and gliding motility o ...200616714562
field study of the efficacy of halofuginone and decoquinate in the treatment of cryptosporidiosis in veal calves.ninety, seven- to 10-day-old calves were allocated to three groups of 30 and treated daily for seven days with either 100 microg/kg halofuginone hydrobromide or 2.5 mg/kg decoquinate orally or left untreated as controls. the levels of diarrhoea and dehydration were monitored daily for 28 days from the first day of treatment (day 0) and samples of faeces were collected on days 0, 7, 14, 21 and 28, to quantify the excretion of cryptosporidium parvum oocysts. the calves were weighed on days 3 and 2 ...200617099176
prevalence and first genetic identification of cryptosporidium spp. in cattle in central viet nam.we investigated the prevalence of cryptosporidium infection in relation to age and clinical status in cattle in the central region of viet nam. a total of 266 fecal samples from diarrheic and non-diarrheic cattle were examined by the modified ziehl-neelsen staining method. prevalence of cryptosporidium parvum type infections, those of the cryptosporidium andersoni type, and mixed infection of both types was 33.5% (89/266), 5.6% (15/266), and 3.4% (9/266), respectively. the infection rate of 44.3 ...200717964078
distribution of cryptosporidium parvum subtypes in calves in eastern united states.cryptosporidium parvum dna from 175 neonatal calves on 16 farms in eight eastern states in the united states was subtyped by sequence analysis of the 60-kda glycoprotein gene to determinate the parasite genetic diversity. six subtypes of the iia subtype family were found. subtype iiaa15g2r1, which is the predominant c. parvum subtype in calves in many parts of the world, was identified in 77% of the c. parvum dna from calves. several farms had more than one c. parvum subtype and a few calves had ...200717024351
prevalence and molecular characterization of giardia duodenalis and cryptosporidium spp. in dairy cattle in ontario, canada.giardia duodenalis and cryptosporidium spp. are intestinal protozoan parasites that infect a wide range of host species, including humans. molecular characterization of these parasites has demonstrated that a number of genotypes and species are common to both humans and animals, and that zoonotic transmission may occur. numerous studies have reported a high prevalence of g. duodenalis and cryptosporidium spp. in cattle, particularly calves, and these animals are frequently associated with zoonot ...200717964724
cryptosporidium and dairy cattle in the catskill/delaware watershed: a quantitative risk assessment.we carried out a study to estimate the public health risk posed by dairy cattle located in new york city's catskill/delaware watershed, as measured by daily c. parvum-like oocyst loading. a monte carlo simulation model that takes into account the nature of the dairy cattle population within the target area, age-specific incidence/prevalence rates, as well as differential fecal production and oocyst-shedding intensity rates was used to address the objectives. additionally, the model was designed ...200718093047
molecular identification of cryptosporidium spp. from fecal samples of felines, canines and bovines in the state of são paulo, brazil.the objective of this study was to obtain information of epidemiological nature through genotypic characterization of cryptosporidium isolates from dogs, cats and bovines from the state of são paulo, brazil. the extraction of dna from oocysts was carried out and polymerase chain reaction was accomplished using specific primers to 18s rrna gene. the amplicons were directed sequenced. seven cat samples, nine dog samples and nine bovine samples were analysed. from the seven cat samples the genotypi ...200717996373
cryptosporidium parvum (eucoccidiorida: cryptosporiidae) in calves: results of a longitudinal study in a dairy farm in sfax, tunisia.a longitudinal study was undertaken to determine the prevalence of cryptosporidium in a dairy farm in sfax, tunisia. 480 faecal samples were obtained from 30 calves under one month of age. all faecal samples were analysed for cryptosporidium oocysts by microscopic examination of smears stained by modified ziehl neelsen technique. the parasite was detected in 26 calves (86.7%). infection was significantly associated with diarrhoea. a molecular characterization, performed in seven calves, confirme ...200718225419
investigation into the prevalence of bovine cryptosporidiosis among small-holder dairy households in dagoretti division, nairobi, kenya.to determine the prevalence of bovine cryptosporidiosis and knowledge of this disease among smallholder dairy households in dagoretti division, nairobi, kenya.200718338725
[the identification of cryptosporidium species (protozoa) in ifsahan, iran by pcr-rflp analysis of the 18s rrna gene].cryptosporidium is an important protozoan that cause diarrheal illness in humans and animals. different species of cryptosporidium have been reported and it is believed that species characteristics are an important factor to be considered in strategic planning for control. we therefore analyzed oocysts from human and animal isolates of cryptosporidium by pcr-rflp to determine strain variation in isfahan. in total, 642 human fecal samples from children under five years of age, immunocompromised p ...200718240576
field scale quantification of microbial transport from bovine faeces under simulated rainfall events.the dispersion and transport of cryptosporidium parvum oocysts, escherichia coli and prd1 bacteriophage seeded into artificial bovine faecal pats was studied during simulated rainfall events. experimental soil plots were divided in two, one sub-plot with bare soil and the other with natural vegetation. simulated rainfall events of 55 mm.h(-1) for 30 min were then applied to the soil plots. each experimental treatment was performed in duplicate and consisted of three sequential artificial rainfal ...200717402281
natural infection with zoonotic subtype of cryptosporidium parvum in capybara (hydrochoerus hydrochaeris) from brazil.a total of 145 capybara (hydrochoerus hydrochaeris) fecal samples from the state of são paulo, brazil, were screened for cryptosporidium spp. oocysts using the malachite green method. eight samples (5.52%) showed positive results and were further submitted to nested pcr reaction for amplification of fragments of 18s rrna gene and 60-kda glycoprotein gene for determination of species, alleles and subtypes of cryptosporidium. sequencing of the pcr products of the 18s rrna gene fragments and 60-kda ...200717467175
detection and quantification of cryptosporidium in hct-8 cells and human fecal specimens using real-time polymerase chain reaction.cryptosporidium is a significant cause of diarrheal illness worldwide, especially among children and immunocompromised patients. currently used diagnostic techniques are time-consuming, require skilled technicians, and are not useful for quantification of oocysts in fecal and environmental samples. in this study, we examined the use of a real-time polymerase chain reaction (pcr) assay for detecting and quantifying cryptosporidium parvum in three distinct and progressively more complex matrices: ...200717488919
a rapid method for producing highly purified cryptosporidium parvum oocysts.most procedures that have been described for purifying cryptosporidium parvum oocysts are designed to either identify the parasites in clinical specimens or isolate oocysts from a small volume of feces from infected animals. the present study describes a rapid method for purifying high numbers of c. parvum oocysts from feces of infected calves that contains minimal contaminating fecal material and bacteria. the isolation method is based on differential flotation of c. parvum oocysts in nacl, fol ...200717539434
phylogenetic analysis implicates birds as a source of cryptosporidium spp. oocysts in agricultural watersheds.cryptosporidium parvum and c. hominis are protozoan parasites responsible for cryptosporidiosis, an acute gastrointestinal illness that can be life-threatening for immunocompromised persons. sources and genotypes of cryptosporidium oocysts were investigated in two agricultural areas within the wachusett reservoir watershed, a drinking water source for boston, massachusetts. two brooks (denoted brook sf and brook jf, respectively), each downgradient from a dairy farm, were chosen as sample sites. ...200717547187
occurrence of cryptosporidium parvum and giardia duodenalis in healthy adult domestic ruminants.to determine the prevalence and intensity of infection of cryptosporidium spp. and giardia duodenalis in healthy adult domestic ruminants, faecal samples were collected from 379 cattle of between 3 and 13 years old, 446 sheep and 116 goats selected at random from 60 dairy farms and 38 and 20 herds, respectively, in galicia (nw spain). cryptosporidium spp. oocysts were detected in 32 cows (8.4%), 24 sheep (5.3%) and in nine goats (7.7%) from, respectively, 48.3% of the farms and 34.2 and 30.0% of ...200717569991
calf-level risk factors for neonatal diarrhea and shedding of cryptosporidium parvum in ontario dairy calves.this work was conducted to investigate calf-level factors that influence the risk of neonatal diarrhea and shedding of cryptosporidium parvum oocysts in calves, on dairy farms in ontario with histories of calf diarrhea or cryptosporidiosis. fecal samples were collected weekly for 4 weeks from each of 1045 calves under 30 days of age on 11 dairy farms in south-western ontario during the summer of 2003 and the winter of 2004. a questionnaire designed to gather information on calf-level management ...200717602767
characterization of subtilase protease in cryptosporidium parvum and c. hominis.cryptosporidium spp., enteropathogens of humans and other animals, are members of the apicomplexa. in parasites belonging to this phylum, proteases have been shown to play a key role in the invasion of host cells, organelle biogenesis, and intracellular survival. the subtilases constitute a family of serine proteases present in prokaryotes, eukaryotes, and viruses. the c. parvum subtilase gene, cpsub1, encodes a transcript of 3972 base pairs (bp) and 1324 amino acids. using homologous polymerase ...200717626354
multilocus analysis of cryptosporidium hominis and cryptosporidium parvum isolates from sporadic and outbreak-related human cases and c. parvum isolates from sporadic livestock cases in the united kingdom.cryptosporidium parvum and cryptosporidium hominis isolates from sporadic, drinking water-associated, and intrafamilial human cases together with c. parvum isolates from sporadic cases in livestock were collected in the united kingdom between 1995 and 1999. the isolates were characterized by analysis of three microsatellite markers (ml1, gp15, and ms5) using pcr amplification. within c. hominis, four alleles were detected within the gp15 and ms5 loci, and a single type was detected with ml1. c. ...200717687021
more productive in vitro culture of cryptosporidium parvum for better study of the intra- and extracellular phases.the great difficulties in treating people and animals suffering from cryptosporidiosis have prompted the development of in vitro experimental models. due to the models of in vitro culture, new extracellular stages of cryptosporidium have been demonstrated. the development of these extracellular phases depends on the technique of in vitro culture and on the species and genotype of cryptosporidium used. here, we undertake the molecular characterization by polymerase chain reaction-restriction frag ...200717710300
transmission dynamics of cryptosporidium infection in a natural population of non-human primates at polonnaruwa, sri lanka.infections from cryptosporidium parvum are of interest not only to public health, but also to wildlife conservation, particularly when humans and livestock encroach on nature and thereby increase the risk of cross-species transmissions. to clarify this risk, we used polymerase chain reaction to examine the hypervariable region of the c. parvum 18s rrna gene in feces from three monkey species. samples were isolated from regions where disease transmission between monkeys, livestock, and humans was ...200717984333
cryptosporidium parvum infection in cattle: are current perceptions accurate?the perception 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 might not reflect the whole situation. numerous management factors influence the epidemiological and clinical picture associated with c. parvum infections in cattle. whereas c. parvum is highly prevalent in young dairy calves and confined beef calves, it occurs rarely in calves on range and in adult cattle. in well-managed h ...200717826336
role of murine peyer's patch lymphocytes against primary and challenge infections with cryptosporidium parvum.in order to determine the role of peyeros patch lymphocytes (ppl) in self-clearing of cryptosporidium parvum infection in murine models, changes in ppl subsets, their cytokine expression, and in vitro igg1 and iga secretions by ppl were observed in primary- and challenge-infected c57bl/6 mice. in primary-infected mice, the percentages of cd4+ t cells, cd8+ t cells, siga+ b cells, il-2+ t cells, and ifn-gamma+ t cells among the ppl, increased significantly (p < 0.05) on day 10 post-infection (pi) ...200717876162
cryptosporidiosis in saudi arabia and neighboring countries.cryptosporidium is a coccidian protozoan parasite of the intestinal tract that causes severe and sometimes fatal watery diarrhea in immunocompromised patients, and self-limiting but prolonged diarrheal disease in immunocompetent individuals. it exists naturally in animals and can be zoonotic. although cryptosporidiosis is a significant cause of diarrheal diseases in both developing and developed countries, it is more prevalent in developing countries and in tropical environments. we examined the ...200717921688
asymptomatic cryptosporidiosis in zambian dairy farm workers and their household members.the prevalence of cryptosporidium and the possibility of zoonotic transmission on dairy farms were examined. eighteen cases of cryptosporidiosis (prevalence 6%) were identified in 82 farm workers and 207 household members. furthermore, 70 (34%) of 207 calf samples were positive. based on the 70kda heat shock protein and the 18s rdna gene, cryptosporidium parvum was identified in 75% of the positive farm workers and in 60% of the household members. of the positive calves, 62% were infected with c ...200717368697
genotype and subtype analyses of cryptosporidium isolates from cattle in hungary.seventy-nine faecal samples from calves with diarrhoea were collected on 52 farms from different counties in hungary to investigate the species, genotypes and subtypes of cryptosporidium in calves. oocysts from faecal sample collected from each animal were concentrated using sucrose gradient centrifugation and examined by immunofluorescence assay (ifa). genomic dna was extracted from microscopically positive samples and nested pcr was performed to amplify the partial ssu rrna and gp60 genes of c ...200717391853
genotypic characterization of cryptosporidium oocysts isolated from healthy people in three different counties of korea.to investigate cryptosporidium infection among healthy people, we collected stool samples from 150 healthy individuals in gokseong, muan, and imshil counties, southwest korea, where neighbors on both an animal farm and a river respectively. in 12 of 150 samples, cryptosporidium oocysts were detected by means of modified acid-fast staining. the bovine genotype, cryptosporidium parvum, was identified by pcr/rflp and 18s rrna sequencing. c. parvum existed endemically in these areas, and the residen ...200717984603
pcr amplification and sequence analyses of its-1 rdna from cryptosporidium andersoni in dairy cattle.the internal transcribed spacer 1 (its-1) of the ribosomal dna (rdna) from gd, hn, and ah strains of cryptosporidium andersoni was amplified and sequenced to assess whether the its-1 rdna could be used as genetic markers of c. andersoni from different geographic origins in china and to differentiate c. andersoni from other cryptosporidium species. the result showed that the its-1 sequences of gd, hn, and ah strains were basically identical, which were unequivocally different with the sequences o ...200717096139
an outbreak of cryptosporidiosis suspected to be related to contaminated food, october 2006, sakai city, japan.on october 17, 2006, the sakai city public health center received a report of acute gastroenteritis among 4 members from the same company who had eaten raw meat dish called "yukke: korean-style beef tartar" and raw liver at a rotisserie in sakai city on october 7. based on information from interviews, the median incubation period was 5.5 (range, 5-7 days), and the median length of illness was 7 days (range, 4-10 days). the illness was characterized by a prolonged incubation period, non-bloody wa ...200718032847
cryptosporidium parvum: identification of a new surface adhesion protein on sporozoite and oocyst by screening of a phage-display cdna library.cryptosporidium parvum is a significant cause of diarrheal disease worldwide. the specific molecules that mediate c. parvum-host interaction and the molecular mechanisms involved in the pathogenesis are unknown. in this study we described a novel phage display method to identify surface adhesion proteins of c. parvum. a cdna library of the sporozoite and oocyst stages of c. parvum expressed on the surface of t7 phage was screened with intestinal epithelial cells (iecs) from the newborn cryptospo ...200717097085
prevalence of cryptosporidium species and genotypes in mature dairy cattle on farms in eastern united states compared with younger cattle from the same locations.feces collected from 541 milking cows on two dairy farms each in vermont, new york, pennsylvania, maryland, virginia, north carolina, and florida were examined for the presence of cryptosporidium oocysts. oocysts were concentrated from 15 g of feces from each cow and dna was extracted. a two-step nested pcr protocol was used to amplify an 830 base pair fragment of the ssurrna gene. pcr-positive products were purified and sequenced. pcr-positive findings were obtained from cows in all seven state ...200717287086
molecular characterization of cryptosporidium isolates from humans and animals in iran.isolates of cryptosporidium spp. from human and animal hosts in iran were characterized on the basis of both the 18s rrna gene and the laxer locus. three cryptosporidium species, c. hominis, c. parvum, and c. meleagridis, were recognized, and zoonotically transmitted c. parvum was the predominant species found in humans.200717142364
genotypes and subtypes of cryptosporidium spp. in neonatal calves in northern ireland.cryptosporidium spp. in diarrheic calves less than 30 days old from farms across northern ireland were examined over a year period by microscopic, genotyping, and subtyping techniques to characterize the transmission dynamics. cryptosporidium oocysts were detected in 291 of 779 (37.4%) animals. the prevalence rates of rotavirus, coronavirus, and escherichia coli k99+ were lower as seen in 242 of 806 (30.0%), 46/806 (5.7%), and 16/421 (3.8%) of animals, respectively. of the 224 cryptosporidium-po ...200717031699
subtype analysis of cryptosporidium parvum isolates from calves on farms around belgrade, serbia and montenegro, using the 60 kda glycoprotein gene sequences.cryptosporidium parvum is composed of multiple subtypes, which appear to be zoonotic or anthroponotic. therefore, in order to understand the molecular epidemiology of this species and to control the zoonotic transmission, it is essential to identify the isolates at the subtype level. in the present study, 60.2% of 103 examined dairy calves from 10 farms in the belgrade area were positive for cryptosporidium infection by pcr, and all of them were identified as c. parvum by pcr-rflp of ssurrna and ...200717076920
wide geographic distribution of cryptosporidium bovis and the deer-like genotype in bovines.recent studies in the united states reported that approximately 85% of pre-weaned dairy calves were infected with zoonotic cryptosporidium parvum, whereas only 1-2% of post-weaned calves and 1-2-year-old heifers were infected with this species. cryptosporidium bovis and cryptosporidium deer-like genotype were much more prevalent in the post-weaned animals. it is not clear whether the same infection pattern also occurs in other geographic areas. in this study, to determine whether the same crypto ...200717097231
development of two immunochromatographic tests for the serodiagnosis of bovine babesiosis.in this study, we developed two immunochromatographic tests (icts), which are nitrocellulose membrane-based immunoassays for the convenient and rapid serodiagnosis of bovine babesiosis caused by babesia bovis (boict) and babesia bigemina (biict). the efficacy of two icts was evaluated using 13 positive sera from experimentally infected cattle with b. bovis or b. bigemina. clear results showed that the boict and elisa detected antibodies in sera collected from 14 to 93 days post-infection, while ...200717590275
the population structure of the cryptosporidium parvum population in scotland: a complex picture.we genotyped 297 scottish c. parvum samples using micro- and minisatellites. treated as a single population, the population structure was epidemic. when regional populations were analysed, there was evidence of sub-population structure variations. this was dependent upon excluding sub-groups exhibiting significant genetic distance from the main population, implying genetic sub-structuring. we tested the hypothesis that these sub-groups originated outside the uk and demonstrated that one sub-grou ...200818077222
development of a rapid immunochromatographic test for simultaneous serodiagnosis of bovine babesioses caused by babesia bovis and babesia bigemina.with the objective of developing a simpler diagnostic alternative, a rapid immunochromatographic test (boiict) was constructed for the simultaneous detection of babesia bovis- and babesia bigemina-specific antibodies using b. bovis recombinant merozoite surface antigen-2c and b. bigemina recombinant rhoptry-associated protein-1. the boiict selectively detected specific antibodies to b. bovis and b. bigemina. all sera from cattle infected with other protozoan parasites (i.e., cryptosporidium parv ...200818187794
host-shaped segregation of the cryptosporidium parvum multilocus genotype repertoire.cattle are among the major reservoirs of cryptosporidium parvum in nature. however, the relative contribution of c. parvum oocysts originating from cattle to human disease burden is difficult to assess, as various transmission pathways -- including the human to human route -- can co-occur. in this study, multilocus genotype richness of representative samples of human and bovine c. parvum are compared statistically using analytical rarefaction and non-parametric taxonomic richness estimators. res ...200817394677
association between management practices and within-herd prevalence of cryptosporidium parvum shedding on dairy farms in southern ontario.to identify management practices associated with an increased within-herd prevalence of cryptosporidium parvum shedding on dairy farms in southern ontario, fecal samples were taken from 1089 calves aged 7-28 days, from 119 herds. information on management practices was obtained by administering a questionnaire compiled using a modified delphi technique. data were analyzed using univariable and multivariable negative binomial regression. overall, 30% of the calves in the study were shedding c. pa ...200817481752
genetic diversity and zoonotic potential of cryptosporidium parvum causing foal diarrhea.cryptosporidium isolates from diarrheic foals in new zealand (n = 9) were identified as c. parvum, subtyped at two polymorphic loci, and compared with human (n = 45) and bovine (n = 8) isolates. foal c. parvum isolates were genetically diverse, markedly similar to human and bovine isolates, and carried gp60 iiaa18g3r1 alleles, indicating a zoonotic potential.200818508944
preventive and therapeutic efficacy of halofuginone-lactate against cryptosporidium parvum in spontaneously infected calves: a centralised, randomised, double-blind, placebo-controlled study.the preventive and therapeutic efficacy of halofuginone-lactate (hfl) against cryptosporidium parvum was evaluated in a study conducted from november 2004 to march 2005 on a dairy farm in central bohemia, czech republic, using 260 spontaneously infected calves. hfl (0.1 mg/kg/day) was administered orally for 7 days to 1-day-old and 8-day-old calves, respectively. in both treated groups the drug significantly, and in almost the same manner, decreased the intensity of diarrhoea (p<0.001) and faeca ...200817606389
effect of cryptosporidium parvum infection on the absorptive capacity and paracellular permeability of the small intestine in neonatal calves.cryptosporidium parvum is recognized as one of the most important pathogens causing enteritis and severe diarrhoea in calves up to 1 month of age. although the infection may be responsible for some mortality, its impact is mainly associated with the impairment of intestinal functions and lower performance of animals. the aim of this study was to determine the effect of cryptosporidiosis on the intestinal functions in neonatal experimentally infected holstein calves. absorption tests with d-xylos ...200818248900
prevalence and molecular characterization of bovine cryptosporidium isolates in india.a survey based on pcr assay of 18s ssu rrna gene revealed a 30.2% infection with cryptosporidium spp., out of 457 faecal samples collected from neonatal bovine calves across three different regions of india. the pcr-rflp pattern of the gene in all the positive cases established the species as cryptosporidium parvum. highest prevalence was recorded in the monsoon months (37.3%) and in the calves showing acute diarrhoea (32.3%). the calves below 15 days of age were mostly affected (45.1%). the inf ...200818346854
feeding activated charcoal from bark containing wood vinegar liquid (nekka-rich) is effective as treatment for cryptosporidiosis in calves.the effect of activated charcoal containing wood vinegar liquid (nekka-rich) on cryptosporidium parvum was evaluated in vitro and in vivo. first, the adsorption of c. parvum by the activated charcoal component of nekka-rich was examined. when mixed, c. parvum oo-cysts were effectively adsorbed by activated charcoal. next, the effect of the wood vinegar liquid component of nekka-rich was assessed. wood vinegar liquid had an antiprotozoan activity against c. parvum oocysts. finally, the anticrypto ...200818349239
zoonotic cryptosporidiosis.the widespread usages of molecular epidemiological tools have improved the understanding of cryptosporidiosis transmission. much attention on zoonotic cryptosporidiosis is centered on cryptosporidium parvum. results of genotype surveys indicate that calves are the only major reservoir for c. parvum infections in humans. the widespread presence of human-adapted c. parvum, especially in developing countries, is revealed by recent subtyping and multilocus typing studies, which have also demonstrate ...200818205803
cryptosporidium from tortoises: genetic characterisation, phylogeny and zoonotic implications.cryptosporidiosis is a disease caused by apicomplexan parasites of the genus cryptosporidium, which affect the gastrointestinal tract of humans and animals worldwide. in the present study, cryptosporidium isolates from captive european tortoises (testudo graeca, testudo hermanni and testudo marginata) in italy were genetically characterised using gene/s encoding cryptosporidium oocyst wall protein (cowp) and/or the hypervariable segment internal to the ssu rdna. six isolates from t. graeca, t. h ...200818234467
near real-time detection of cryptosporidium parvum oocyst by igm-functionalized piezoelectric-excited millimeter-sized cantilever biosensor.piezoelectric-excited millimeter-sized cantilever (pemc) biosensors were fabricated and functionalized with immunoglobulin m (igm) for the detection of cryptosporidium parvum oocyst in a flow configuration at 1 ml/min. the detection of 100, 1000, and 10,000 oocysts/ml was achieved with a positive sensor response in less than 1 min. bovine serum albumin (bsa) was used as a blocking agent in each experiment and was shown to eliminate non-specific binding. the sensor's resonance frequency response ...200818054480
molecular epidemiology of cryptosporidium in humans and cattle in the netherlands.the protozoan parasite cryptosporidium is found world-wide and can cause disease in both humans and animals. to study the zoonotic potential of cryptosporidium in the netherlands we isolated this parasite from the faeces of infected humans and cattle and genotyped those isolates for several different markers. the overall genotyping results showed: for humans isolates, 70% cryptosporidium hominis, 19% cryptosporidium parvum, 10% a combination of c. hominis and c. parvum, and 1% cryptosporidium fe ...200818054936
detection of cryptosporidium oocysts in fresh and frozen cattle faeces: comparison of three methods.the aim of this study was to compare the performance of three commonly used screening tests for cryptosporidium oocysts in fresh and frozen cattle faeces.200817944836
fecundity of cryptosporidium parvum is correlated with intracellular levels of the viral symbiont cpv.differences in the virulence and fecundity of cryptosporidium parvum isolates have been observed by several researchers studying cryptosporidiosis. the purpose of the present study was to determine if there was a correlation between intracellular levels of the viral symbiont cpv in c. parvum and fecundity of two isolates of the parasite, namely c. parvum beltsville (b) and c. parvum iowa (i). dairy calves infected with 10(6)c. parvum-b excreted 5-fold more oocysts compared with calves infected w ...200818096164
distribution of cryptosporidium parvum subtypes in calves in germany.cryptosporidium dna was extracted from 134 faecal specimens from pre-weaned calves from different german federal states (age range, 3-15 days old), which tested positive for oocysts by microscopic analysis. the 18s rdna gene and the oocyst wall protein gene (cowp) were used as targets for pcr and rflp techniques. cryptosporidium species were identified by using sspi, mboii and rsai endonucleases for the digestion of 18s rdna and cowp amplified fragments, respectively. in all samples, restriction ...200818394808
molecular characterization of cryptosporidium isolates from human and bovine using 18s rrna gene in shahriar county of tehran, iran.cryptosporidiosis is a widespread cause of diarrheal diseases of humans, young calves, and many mammals. although in recent years molecular investigations on cryptosporidium have increased, no data are available on iran in this regard. two species of cryptosporidium are known to infect human beings; cryptosporidium hominis which shows anthroponotic transmission among humans and cryptosporidium parvum which shows zoonotic transmission between animals and humans. cryptosporidium oocysts, morpholog ...200818478266
outbreak of cryptosporidiosis among veterinary students.in january 2007, six veterinary students became infected with cryptosporidium species, and records indicated that another student had been diagnosed in november 2006. it was established that the seven students had worked with cattle from the same farm. microbiological tests indicated that they were infected with cryptosporidium parvum. subtyping by sequence analysis indicated a common source of infection for five of the students, but there was insufficient material to type the other two samples. ...200818587060
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
first report of cryptosporidium deer-like genotype in malaysian cattle.fifty faecal samples from diarrheic calves between 1 and 6 months old were collected per rectum from 5 farms around petaling district in selangor, malaysia for cryptosporidium species detection and genotyping investigation. oocysts were purified using sedimentation and gradient centrifugation, then examined by immunofluorescence assay (ifat). genomic dna was extracted from all samples and nested pcr was performed to amplify the ssu rrna gene. eighteen samples (36%) were positive for cryptosporid ...200818289793
evidence supporting zoonotic transmission of cryptosporidium in rural new south wales.cryptosporidium hominis, which has an anthroponotic transmission cycle and cryptosporidium parvum, which is zoonotic, are the primary species of cryptosporidium that infect humans. the present study identified the species/genotypes and subgenotypes of cryptosporidium in 7 human and 15 cattle cases of sporadic cryptosporidiosis in rural western nsw during the period from november 2005 to january 2006. the species/genotype of isolates was determined by pcr sequence analysis of the 18s rrna and c. ...200818343369
influence of land use and watershed characteristics on protozoa contamination in a potential drinking water resources reservoir.relative changes in the microbial quality of lake texoma, on the border of texas and oklahoma, were investigated by monitoring protozoan pathogens, fecal indicators, and factors influencing the intensity of the microbiological contamination of surface water reservoirs. the watershed serves rural agricultural communities active in cattle ranching, recreation, and is a potential drinking water source. a total of 193 surface water samples were tested over a 27-month period to determine levels of pa ...200818367230
detection and species identification of cryptosporidium from taiwan feeding animals.in this study, 107 fecal specimens were collected from 40 sampling sites in taiwan livestock and avian farms to test for cryptosporidium spp. oocysts. ten of 107 samples analyzed by enzyme-linked immunosorbent assay showed the presence of cryptosporidium spp., among which 6 samples were simultaneously confirmed by immunofluorescence assay and polymerase chain reaction. nucleic acid sequencing of the 18s rrna gene identified 3 clusters of cryptosporidium spp. three cryptosporidium parvum isolates ...200818372647
classification of cryptosporidium species from patients with sporadic cryptosporidiosis by use of sequence-based multilocus analysis following mutation scanning.in the present study, we analyzed genetic variation in cryptosporidium species from humans (n = 62) with clinical cryptosporidiosis in south australia. sequence variation was assessed in regions within the small subunit of nuclear rrna (p-ssu), the 70-kda heat shock protein (p-hsp70), and the 60-kda glycoprotein (p-gp60) genes by employing single-strand conformation polymorphism analysis and sequencing. based on the analyses of p-ssu and p-hsp70, cryptosporidium hominis (n = 38) and cryptosporid ...200818448696
binding and activation of human and mouse complement by cryptosporidium parvum (apicomplexa) and susceptibility of c1q- and mbl-deficient mice to infection.cryptosporidium parvum is a protozoan parasite (apicomplexa) that causes gastrointestinal disease in animals and humans. whereas immunocompetent hosts can limit the infection within 1 or 2 weeks, immunocompromised individuals develop a chronic, life-threatening disease. the importance of the adaptive cellular immune response, with cd4+ t-lymphocytes being the major players, has been clearly demonstrated. several non-adaptive immune mechanisms have been suggested to contribute to the host defence ...200818501966
comparison of various staining methods for the detection of cryptosporidium in cell-free culture.the complete development of cryptosporidium in host cell-free medium first described in 2004, represented a significant advance that can facilitate many aspects of cryptosporidium research. a current limitation of host cell-free cultivation is the difficulty involved in visualising the life-cycle stages as they are very small in size, morphologically difficult to identify and dispersed throughout the media. this is in contrast to conventional cell culture methods for cryptosporidium, where it is ...200818547565
substance p receptor antagonism for treatment of cryptosporidiosis in immunosuppressed mice.cryptosporidiosis, caused by the protozoan parasite cryptosporidium parvum, causes self-limited diarrhea in normal hosts but can cause life-threatening diarrhea for immunosuppressed patients. there is an urgent need for new drugs to treat this chronic disease. cryptosporidium parvum infection is associated with intestinal structural and pathophysiologic changes, including villi blunting and glucose malabsorption. substance p (sp), a neuropeptide and pain transmitter, is associated with the gastr ...200818576802
cryptosporidium ryanae n. sp. (apicomplexa: cryptosporidiidae) in cattle (bos taurus).a new species, cryptosporidium ryanae, is described from cattle. oocysts of c. ryanae, previously identified as the cryptosporidium deer-like genotype and recorded as such in genbank (ay587166, eu203216, dq182597, ay741309, and dq871345), are similar to those of cryptosporidium parvum and cryptosporidium bovis but smaller. this genotype has been reported to be prevalent in cattle worldwide. oocysts obtained from a calf for the present study are the smallest cryptosporidium oocysts reported in ma ...200818583057
microbial adhesion of cryptosporidium parvum: identification of a colostrum-derived inhibitory lipid.we previously described an unidentified lipid purified from calf small intestine that inhibits the in vitro adhesion of cryptosporidium parvum sporozoites to host cells [johnson jk, schmidt j, gelberg hb, kuhlenschmidt ms. microbial adhesion of cryptosporidium parvum sporozoites: purification of an inhibitory lipid from bovine mucosa. j parasitol 2004;90:980-90]. intestinal mucosa from some calves, however, failed to yield this bioactive lipid. accordingly, we examined other potential sources, e ...200818675305
detection of cryptosporidium parvum oocysts by dot-blotting using monoclonal antibodies to cryptosporidium parvum virus 40-kda capsid protein.monoclonal antibodies (mab) were prepared against the 40-kda capsid protein of cryptosporidium parvum virus (cpv) by immunizing mice with purified recombinant cpv40 protein. in immunoblotting analysis, mabcpv40-1 bound to a 40-kda protein in extracts of c. parvum oocysts. this 40-kda protein was localized in the sporozoite cytoplasm by immunofluorescence (ifa) staining with mabcpv40-1. in a dot-blot assay, mabcpv40-1 was capable of detecting 10(2) non-bleach-treated and 10(2)-10(3) bleach-treate ...200818372626
host cell actin remodeling in response to cryptosporidium.cryptosporidium exhibits a complex strategy to invade and establish productive infection sites, involving complimentary parasite and host cell processes. while the work regarding host cell actin remodeling has greatly enhanced our understanding of the molecular pathways involved in the parasite induced actin reorganization, the specific function of host cell actin remodeling is still equivocal. we contend that host cell actin polymerization contributes to the development of productive c. parvum ...200818512344
recombinant cryptosporidium parvum p23 as a target for the detection of cryptosporidium-specific antibody in calf sera.cryptosporidium parvum is a widely distributed coccidian parasite and causes enteric disease in humans and animals. in addition to being a cause of life-threatening disease in immunodeficient people, mostly aids patients, c. parvum has been reported as a common serious primary cause of outbreaks of diarrhea in newborn calves, especially newborn ruminants (de graaf et al. in int j parasitol 29:1269-1287, 1999). to obtain the recombinant p23 protein, we isolated the mrna from oocyst of c. parvum a ...200818677624
cryptosporidium species and subtype analysis from dairy calves in spain.faecal specimens from 287 diarrhoeic calves younger than 21 days, collected over a 2-year period (2006-2007) from 82 dairy cattle farms in 14 provinces across the north of spain, were examined for the presence of cryptosporidium oocysts. overall, 63 farms (76.8%) and 166 calves (57.8%) tested positive by microscopy. in order to elucidate the genetic diversity, selected positive specimens from 149 calves originating from 61 farms in the 14 provinces were examined by genotyping and subtyping techn ...200818980704
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
prevalence of four enteropathogens in the faeces of young diarrhoeic dairy calves in switzerland.the prevalences of cryptosporidium parvum, rotavirus, bovine coronavirus (bcv), and enterotoxigenic escherichia coli (e coli k99) were determined in diarrhoeic dairy calves aged one to 21 days on 71 dairy farms in western switzerland during the winter of 2005 to 2006. faecal samples from 147 untreated calves suffering from acute diarrhoea were analysed by standardised diagnostic methods, and the immunoglobulin status of each calf was evaluated. the prevalences of c parvum, rotavirus, bcv and e c ...200818806281
targeting a uniquely nonspecific prenyl synthase with bisphosphonates to combat cryptosporidiosis.cryptosporidiosis is a neglected disease without a wholly effective drug. we present a study demonstrating nitrogen-containing bisphosphonates (n-bps) to be capable of inhibiting cryptosporidium parvum at low micromolar concentrations in infected mdck cells. predictably, the mechanism of action is based on inhibition of biosynthesis of isoprenoids but the target enzyme is unexpectedly a distinctive c. parvum enzyme dubbed nonspecific polyprenyl pyrophosphate synthase (cpnppps). this enzyme produ ...200819101474
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
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
pathophysiology of diarrhea in calves.infectious diarrhea in calves is most commonly associated with enterotoxigenic escherichia coli, cryptosporidium parvum, rotavirus, coronavirus, or some combination of these pathogens. each of these agents leads to diarrhea through either secretion or malabsorption/maldigestion, though the specific mechanisms and pathways may differ. specific pharmacologic control and treatment are dependent on gaining a greater understanding of the pathophysiology of these organisms.200919174281
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
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