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1.
Prevalences of Cryptosporidium spp. oocysts in cattle (n = 486) on five selected farms in Morogoro municipality and three species of herbivorous wildlife (n = 87) from Mikumi National Park, Morogoro, Tanzania, were determined using the modified Ziehl-Neelsen staining technique. Of 486 bovine faecal samples, 5.3% were positive for Cryptosporidium spp. The prevalence of Cryptosporidium was higher in calves less than 3 months of age compared to weaned calves and adults. Cryptosporidium spp. oocysts were detected in both diarrhoeic and non-diarrhoeic animals, but there was a significantly higher prevalence (P < 0.001) of oocyst shedding in diarrhoeic than in non-diarrhoeic animals. Of the 87 faecal specimens from the wildlife species, 36 were from the African buffaloes (Syncerus caffer), 25 from zebra (Equus zebra) and 26 from the wildebeest (Connochaetes gnou). Cryptosporidium spp. oocysts were detected in eight (22%) buffaloes, seven (28%) zebras and seven (27%) wildebeests. Confirmation of the diagnosis was performed using anti-Cryptosporidium monoclonal antibody specific for Cryptosporidium muris, Cryptosporidium parvum and Cryptosporidium baileyi (Pathasure Cryptosporidium test kit).  相似文献   

2.
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 patterns corresponding to Cryptosporidium parvum were identified, which is in agreement with abundant literature data indicating C. parvum as the most common species in pre-weaned calves. In order to estimate the genetic heterogeneity among C. parvum calf isolates, 53 samples chosen to represent different German Federal States were successfully subtyped by sequence analysis of the highly polymorphic 60-kDa glycoprotein gene. All isolates belonged to the allele IIa (with seven subtypes), with the exception of one isolate that belonged to the allele IId. Moreover, three novel subtypes of the allele family IIa have been found. This study confirms the utility of genotyping and subtyping tools in characterizing the transmission of Cryptosporidium spp. This is the first molecular epidemiological report about subtyping of Cryptosporidium bovine isolates in Germany.  相似文献   

3.
A total of 469 fecal samples were collected from American minks (Mustela vison) on a farm in Hebei Province in China and examined for Cryptosporidium by Sheather's sugar flotation technique and 8 Cryptosporidim isolates were obtained. The partial 18S rRNA, 70 kDa heat shock protein (HSP70), Cryptosporidium oocyst wall protein (COWP) and actin genes of six isolates were sequenced. Sequence data were analyzed together with known Cryptosporidium spp. and genotypes. Results of this multi-locus genetic characterization indicated that the six Cryptosporidium isolates in this study shared the same sequences of the genes studied and were different from known Cryptosporidium species and genotypes. The closest relative was Cryptosporidium ferret genotype with 7, 22, 2 and 2 nucleotide differences in the 18S rRNA, HSP70, COWP and actin genes, respectively. The homology to ferret genotype at the 18S rRNA locus was 99.1%, which is comparable to that between C. parvum and C. hominis (99.2%), or between C. muris and C. andersoni (99.4%). Therefore, the Cryptosporidium in minks in this study is considered a new genotype, the Cryptosporidium mink genotype.  相似文献   

4.
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 zoonotic transmission. In the present study, a total of 143 faecal samples from adults, heifers and calves were collected from two dairy cattle farms in eastern Ontario, Canada. The prevalence and molecular characteristics of G. duodenalis and Cryptosporidium spp. in these animals were determined in order to investigate the potential for transmission between cattle and humans in this region. Following DNA extractions from faecal samples, nested-PCR protocols were used to amplify fragments of the 16S rRNA gene and the heat-shock protein 70 (HSP-70) gene for determining the prevalence of G. duodenalis and Cryptosporidium spp. infections, respectively. Genotypes of G. duodenalis, and species of Cryptosporidium, were determined by means of DNA sequencing of amplicons, and subsequent sequence alignment. Cattle on both farms showed a high prevalence of G. duodenalis (42.0%) and Cryptosporidium spp. (27.3%). G. duodenalis infections were more prevalent in calves and heifers than in adults, and Cryptosporidium spp. infections were only observed in calves and heifers. The zoonotic genotype, G. duodenalis Assemblage B was isolated from 24.5% of the cattle tested, while G. duodenalis Assemblage E was found in 17.5% of the cattle tested. The overall prevalence of the zoonotic species Cryptosporidium parvum in the animals tested was found to be 21.7%, while only 1.4% were infected with C. bovis. These findings suggest that there is a potential risk of zoonotic and/or zooanthroponotic transmission of G. duodenalis and C. parvum infections between cattle and humans in eastern Ontario, likely by means of contaminated water or food, or through direct faecal-oral transmission in the case of farmers and veterinary staff.  相似文献   

5.
A study was undertaken to determine the prevalences of Cryptosporidium and Giardia in dairy calves less than 6 months of age in Norway. Faecal samples were collected from a total of 1386 calves, between 3 and 183 days of age, in 136 dairy farms from three different areas of Norway. Faecal samples were examined for Cryptosporidium oocysts and Giardia cysts after concentration and immunofluorescent staining.

Giardia was found in 93% (127 out of 136) of the farms and in 49% (679 out of 1386) of the calves. Cryptosporidium was found in 53% (72 out of 136) of the farms and in 12% (167 out of 1386) of the calves. The level of Giardia and/or Cryptosporidium was low in the majority of the infected calves.

Infection peaked in the age group 2–3 months for both Cryptosporidium and Giardia. The prevalences of both parasites were higher in samples taken during winter than in samples taken during summer, and statistically significant differences were found when prevalences in different age groups of calves were compared between the three areas. A significantly lower prevalence of Cryptosporidium was found in calves housed in shared pens that were thoroughly washed more than three times a year than in calves from pens washed less often. For Giardia there was a trend for decreasing intensity of infection with increasing age in the sampled calves. For Cryptosporidium there was a trend for increasing herd prevalence with increasing number of calves in the herd, but this trend was not statistically significant. Other parameters which were investigated such as housing, feeding or management routines were not associated with prevalence or intensity of infection with either parasite.  相似文献   


6.
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% (35/79) of C. parvum in calves less than 6 months old was significantly higher than that of 28.9% (54/187) in cattle greater than 6 months old (P < 0.01). Although no C. andersoni oocysts were detected in calves less than 3 months old, no significant difference was observed between the age groups in the prevalence of C. andersoni infection and mixed infection. The percentage of diarrheic and non-diarrheic cattle identified to be shedding C. parvum oocysts was 46.5% (74/159) and 14.0% (15/107), respectively (P < 0.0001). The risk of diarrhea was 1.7 times greater in C. parvum-infected calves than in their non-infected counterparts. DNA sequences of 18S rRNA genes of C. parvum type and C. andersoni type indicated that they were C. parvum bovine genotype and C. andersoni, respectively. This is the first genetic identification of C. parvum bovine genotype and C. andersoni from cattle in Viet Nam.  相似文献   

7.
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 genotypic analyses revealed Cryptosporidium felis in all. These were the first genotypic characterization of Cryptosporidium from domestic felines in Brazil. In nine sequenced samples from dogs, genotypic identities compatible with Cryptosporidium canis were revealed in all samples. The genotypic analyses in bovines revealed Cryptosporidium parvum in eight samples and Cryptosporidium bovis in another sample, the last one being a non-zoonotic species, not related to clinical symptoms and described for the first time in Brazil.  相似文献   

8.
Pathogenic microorganisms in manure represents a potential hazard to human and animal. Few data describing the microbiological content of liquid hog manure intended for spreading are available in the scientific literature. The objective of this project was to verify the presence and estimate the persistence of Escherichia coli, Salmonella spp., Yersinia enterocolitica and Cryptosporidium spp. in liquid hog manure from storages under conditions typical of commercial swine production in Québec. E. coli content of liquid hog manure taken during the spreading period in the 32 hog operations varied between 0 and 5.52 log10 CFU/g with a 95% confidence interval of 3.16–4.23 log10 CFU/g. Salmonella spp., Y. enterocolitica and Cryptosporidium spp. were detected in 37%, 9% and 3% samples, respectively. Under the conditions of this experiment, the predicted number of days required to obtain a 90% reduction of E. coli populations varied between 15 and 26 days, while the predicted storage period necessary to reach undetectable levels was 54–114 days. The maximal persistence of Salmonella observed in this study was 88 days. A 73-day storage time was insufficient for the elimination of Y. enterocolitica.  相似文献   

9.
Cryptosporidium spp. oocyst shedding was observed in calves from approximately 1 to 30 days of age. Oocysts were detected by either the Kinyoun acid-fast staining technique (microscopic examination—ME) or a commercially produced enzyme immunoassay (EIA). Test concordance between the two detection methods was determined. The mean (±SD) number of days to detection of cryptosporidial oocysts was 9.52 ± 1.92 for the ME and 9.83 ± 3.19 for the EIA. No significant difference between the means was found (P = 0.17). The period prevalence of cryptosporidiosis was 100% in calves from 1 to 30 days of age. The overall agreement between the ME and EIA was 72%, with a kappa value of 0.42 (SE ± 0.05). McNemar's test indicated that the proportion of tests determined positive by the two methods was not equal (P < 0.01). The findings of this study indicate moderate agreement between the two diagnostic methods, with the EIA being the more sensitive of the two. However, in most cases the herd-level determination of cryptosporidiosis requires minimal sample size and is more economically and easily accomplished by the ME methvd of detection.  相似文献   

10.
This paper combines the results from a preliminary survey of occurrence of Cryptosporidium species in faecal samples from a range of wild mammal species inhabiting mainland Britain with a tabulated literature review of world-wide reports of the parasite in those British mammals. In the literature, C. parvum was reported from 11 wild mammals found in Britain and elsewhere, mainly in rodents but also in insectivores, lagomorphs and ungulates. C. muris has been reported only in wild rodents. The sample survey detected C. parvum in seven additional British species, including carnivores. Overall, 12% of 184 faecal samples tested with a genus-specific monoclonal antibody contained oocysts of C. parvum. The results further emphasise the widespread distribution of Cryptosporidium amongst wild mammals in Britain, highlight the potential for transmission between host species and warn of the possibility of direct exposure for anybody using the countryside for professional or recreational purposes (e.g. farmers and ramblers) to previously unregarded sources of infection. It seems increasingly likely that most, if not all, mammalian species can be infected with C. parvum.  相似文献   

11.
【目的】调查广东省内部分地区马匹寄生虫感染情况,探索区域内马匹寄生虫感染优势虫种、感染情况和耐药情况,为区域内马肠道寄生虫病的防治提供参考。【方法】采用饱和食盐溶液漂浮法和饱和蔗糖溶液漂浮法对广东省内7个城市24个马术俱乐部375份新鲜马粪样品进行处理,光学显微镜下观察虫卵/卵囊的形态结构特征并进行分类,并根据麦氏计数法计算每克粪便中虫卵/卵囊数(EPG),统计感染率和感染强度。对EPG>500的阳性样本进行粪便虫卵减少量计数试验(FECRT),以评估各马术俱乐部流行寄生虫耐药情况。提取5份<1岁幼驹的粪便样本DNA,利用巢式PCR检测样品是否存在隐孢子虫感染。【结果】375份样品中有120份样品呈寄生虫虫卵/卵囊阳性,总感染率为32.00%。共检出4种肠道寄生虫,分别为圆线虫、马副蛔虫、类圆线虫和马蛲虫,总感染率分别为30.40%、3.70%、0.80%和0.30%。1~4岁马匹感染率显著高于其他年龄段(P<0.05),但不同性别马匹寄生虫感染情况无显著差异(P>0.05)。受调查马匹感染强度以低排卵(EPG<200)为主,占马匹总数83.47%。FEC...  相似文献   

12.
The aim of this study was to investigate the presence of intestinal parasites in pig slurries from several piggeries in Alicante (Spain). Pig slurries were collected in five highly-intensive pig farms (A–E), being sampled in each farm from the pits depending on the production cycle (gestating sows, farrowing sows, weaners, finishers). Samples were concentrated either through zinc sulphate flotation or by formalin–ethyl acetate sedimentation methods. Parasitological examination was performed by optical microscopy. Detection of Cryptosporidium sp. was performed using conventional acid-fast stain and by DNA extraction and PCR amplification. Cryptosporidium genus-specific primers (CPBDIAGF and CPBDIAGR) were used to amplify the Cryptosporidium SSU-rRNA variable region. Intestinal parasites were found in all farms studied. Several protozoa (Ballantidium coli, Entamoeba coli and Cryptosposidium sp.) and helminths (Ascaris suum, Trichuris suis, Fasciola hepatica, Strongylida and nematode larvae) were identified. Parasite viability studies are needed in order to assess the potential risk for animal and human health.  相似文献   

13.
A case-control study of calves under 3 months of age was carried out by weekly visits to 15 farms in the canton of Tilarán, Costa Rica. Most farms were dedicated to beef or dual-purpose (DP) production. Faecal samples were collected over a 6-month period from a total of 194 calves with clinical signs and from 186 animals without clinical signs of diarrhoea as assessed by a scoring system. The samples were investigated for the presence of viruses, bacteria and parasites. Torovirus was detected for the first time in Costa Rica and was present in 14% of calves with diarrhoea and in 6% of the controls. Coronavirus and Rotavirus were less frequently encountered in either one of the groups (in 9 and 7% of scouring calves and in 1 and 2% of controls, respectively). Escherichia coli was detected in 94% of all the faecal samples, but isolates from only three samples from calves with diarrhoea contained the K99 antigen. Similarly, Salmonella was found only in scouring calves. Cryptosporidium oocysts were detected in animals with signs of diarrhoea, while other coccidia oocysts, Strongylida and Strongyloides eggs were frequently found in animals both with and without diarrhoea. A conditional logistic regression (CLR) analysis to compare healthy and scouring calves showed a significant difference with regard to the presence of Torovirus, Rotavirus and Coronavirus.  相似文献   

14.
We examined exogenous and endogenous development of Eimeria procera in experimentally infected grey partridges (Perdix perdix). Our examination included data on morphology, localization, duration of schizogony and gametogony and morphology of sporulated oocysts. The endogenous stages of E. procera developed in large numbers within the epithelial cells of caecal crypts. The asexual development comprised three generations of schizonts. The first fully developed macrogametes and microgamonts were observed on Day 5 post-infection (p.i.) in histologic section. The patent period began on Day 6 p.i. and ended on Day 11 p.i. with peak production of oocysts on Days 7 and 8. Long oval oocysts of E. procera measured 25.78–28.13 μm in length and 14.06–15.24 μm in width, sporulation time ranged from 18 to 24 h at 25°C and from 36 to 48 h at 20°C.  相似文献   

15.
Toxocarosis is a worldwide parasitic infection that affects both cats and dogs. Toxocara cati (Schrank, 1788) syn.Toxocara mystax (Zeder, 1800) prevalence was studied in faeces from stray cats collected from the open spaces of public institutions of Buenos Aires city, both building and surrounding open spaces are fenced off. Of the 465 samples obtained from March to June of 2005, 58.3% were found to have parasite eggs. The following parasites were identified from the 271 positive samples: T. cati (61.2%), Cystoisospora spp. (20.3%), Trichuris spp. (17.0%), Toxascaris leonina (15.1%), Ancylostoma spp. (14%) and Aelurostrongylus abstrusus (2.6%). T. cati prevalence was 35.7% (95% confidence interval: 31.2–40.1), with a 42.2% single isolations. The most frequent combination was T. cati and Cystoisospora spp. (9%). More than half the areas studied showed over 40% prevalence. Seventy-one percent of the collected samples were fresh with a variable moist consistency and 29% were older with a dry consistency. A statistically significant association was found between sample consistency and presence of parasites (χ2 = 10.81; p = 0.001) as also between sample consistency and presence of T. cati (χ2 = 11.27; p = 0.0007). Moist consistencies were significantly different from the rest: consistency (wet or dry) versus parasites (z = 1.95; p = 0.02) (95% confidence interval: 0.004–0.203); consistency (wet or dry) versus T. cati (z = 3.25; p = 0.0006) (95% confidence interval: 0.075–0.254). The cat population that inhabits these public green spaces contaminates the environment, thus transforming them into dangerous spaces with a variable rate for the human population that spends time in these places.  相似文献   

16.
Populational flux of the adult phase of Stomoxys calcitrans was observed in the municipal district of Pedro Leopoldo, Minas Gerais, Brazil. Three biocenoses were selected for the study: stable agrobiocenosis, pastural agrobiocenosis and eubiocenosis. The occurrence and the populational flux of the insects, using the Magoon trap for their capture, were established. For each trap located in different biocenoses, a crossbred calf (Bos taurus × Bos indicus) approximately 6-month-old was used as “live bait,” exposed weekly for 48 h in the traps. Of the three agrobiocenoses studied, the stable agrobiocenosis contributed the greatest number of specimens of. S. calcitrans captured, corresponding to 96.9% of the total flies of this species collected. S. calcitrans shows seasonal behavior for approximately 6 months (spring and summer being the rainiest months of the year). The population peaked during the months of November and December. During the months of July and August, there was no capture of flies.  相似文献   

17.
In a recent study of intestinal parasites in dogs and cats in Australia, Giardia was found to be the most prevalent parasite in dogs. The aim of the current study through the use of molecular tools was to determine the zoonotic significance of the Giardia and Cryptosporidium isolates recovered from dogs and cats during the Australian study. Of the isolates successfully amplified all but one of the Giardia from dogs was either Assemblage C and/or D, with one Assemblage A. Of the cat samples amplified all but one were Assemblage F, with one Assemblage D. We hypothesize that the lack of zoonotic Giardia Assemblages recovered is a result of their being a low prevalence of Giardia in the human population. The Cryptosporidium recovered from dogs and cats was determined to be C. canis and C. felis, respectively, a finding which supports growing evidence that Cryptosporidiumin companion animals is of limited public health significance to healthy people.  相似文献   

18.
Infections by Cryptosporidium spp. in aquatic mammals is a major concern due to the possibility of the waterborne transmission of oocysts. The aim of the present study was to report the occurrence of Cryptosporidium spp. in Antillean manatees (Trichechus manatus) and Amazonian manatees (Trichechus inunguis) from Brazil. Fecal samples were collected and processed using Kinyoun's method. Positive samples were also submitted to the direct immunofluorescence test. The results revealed the presence of Cryptosporidium spp. oocysts in 12.5% (17/136) of the material obtained from the Antillean manatees and in 4.3% (05/115) of the samples from the Amazonian manatees. Cryptosporidium spp. infection was more prevalent in captive animals than in free-ranging specimens.  相似文献   

19.
The present study was conducted to estimate the direct losses due to Neospora caninum in Swiss dairy cattle and to assess the costs and benefits of different potential control strategies. A Monte Carlo simulation spreadsheet module was developed to estimate the direct costs caused by N. caninum, with and without control strategies, and to estimate the costs of these control strategies in a financial analysis. The control strategies considered were “testing and culling of seropositive female cattle”, “discontinued breeding with offspring from seropositive cows”, “chemotherapeutical treatment of female offspring” and “vaccination of all female cattle”. Each parameter in the module that was considered to be uncertain, was described using probability distributions. The simulations were run with 20,000 iterations over a time period of 25 years.

The median annual losses due to N. caninum in the Swiss dairy cow population were estimated to be € 9.7 million. All control strategies that required yearly serological testing of all cattle in the population produced high costs and thus were not financially profitable. Among the other control strategies, two showed benefit–cost ratios (BCR) >1 and positive net present values (NPV): “Discontinued breeding with offspring from seropositive cows” (BCR = 1.29, NPV = € 25 million) and “chemotherapeutical treatment of all female offspring” (BCR = 2.95, NPV = € 59 million). In economic terms, the best control strategy currently available would therefore be “discontinued breeding with offspring from seropositive cows”.  相似文献   


20.
Four controlled trials were conducted to evaluate the therapeutic and persistent efficacy of a new moxidectin formulation (moxidectin 1% nonaqueous injectable) against nematode parasites in cattle. This injectable moxidectin formulation, given as a single subcutaneous injection at a dose rate of 0.02 ml/kg BW to provide 0.2 mg moxidectin/kg BW, was highly efficacious (>90–100%) against larval and/or adult stages of many species of nematodes in cattle including, Dictyocaulus viviparus, Ostertagia spp., Trichostrongylus axei, Haemonchus placei, Trichostrongylus colubriformis, Cooperia spp., Nematodirus helvetianus, Strongyloides papillosus, Oesophagostomum radiatum and Trichuris spp. This formulation had persistent efficacy of >90% against D. viviparus for at least 6 weeks post-treatment, H. placei and Oe. radiatum for 5 weeks post-treatment, and Ostertagia spp. and T. axei for 2 weeks post-treatment.  相似文献   

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