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1.
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 Cryptosporidium parvum. Oocyst load per fly for M. domestica and M. sorbens was 5.84 and 3.42, respectively. Flies’ population dynamics in each month had little relation to the monthly oocyst frequency, r = 0.06 and 0.02 for M. domestica and M. sorbens, respectively. Cryptosporidium species oocysts were isolated from frozen mango juice, which filth flies visited in dairy farm barn. Load of oocysts in the mango juice was dependent on time contact of flies with mango juice and more oocysts were recovered (P < 0.05) in mango juice samples accessed by filth flies for longer period. Role of filth flies to carry and deposit Cryptosporidium species oocyst for development of food‐borne cryptosporidiosis is signified.  相似文献   

2.
《Veterinary parasitology》2015,207(1-2):144-148
This report is the first to describe Cryptosporidium infection in bamboo rats (Rhizomys sinensis). Ninety-two fresh fecal specimens were collected from a pet market in Ya’an City, China. One Cryptosporidium isolate from an asymptomatic host and two isolates from separate hosts with diarrhea were obtained by using Sheather's sucrose flotation technique and modified acid-fast staining. The Cryptosporidium spp. were genotyped by nested PCR and nucleotide sequencing of the small subunit rRNA (SSU rRNA), 70-kDa heat shock protein (HSP70), oocyst wall protein (COWP), and actin genes: isolates were identified as Cryptosporidium parvum with minor nucleotide differences at all four loci. Further subtyping was performed by PCR amplification and DNA sequence analysis of the 60-kDa glycoprotein (gp60) gene: two subtype families were detected, including a novel C. parvum subtype IIpA9 and a rare subtype IIoA13G1 (only reported in diarrheal patients of Sweden). Our results suggest that the bamboo rat is a reservoir host of C. parvum. Significantly, we discovered that the rare C. parvum subtype family IIo is also a zoonotic subtype and confirmed C. parvum subtype IIpA9 as a novel subtype family.  相似文献   

3.
We investigated the response to challenge infection with Cryptosporidium parvum oocysts in immunosuppressed C57BL/6N mice. In the primary infection, fecal oocyst shedding and parasite colonization were greater in immunosuppressed mice than in nonimmunosuppressed mice. Compared with primary infection, challenge infection with C. parvum didn''t show any oocyst shedding and parasite colonization. Especially, oocyst shedding and parasite colonization from the mice infected with heat-killed oocysts were not detected. After challenge infection with C. parvum oocysts, however, these mice were shedding small numbers of oocysts and parasite colonization. Except normal control and uninfected groups, the antibody titers of other groups appear similar. Based on the fecal oocyst shedding, parasite colonization of ilea, and antibody titers in the mice, these results suggest that the resistance to challenge infection with C. parvum in immunosuppressed C57BL/6N mice has increased.  相似文献   

4.
A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.  相似文献   

5.
To obtain information about the occurrence and genotype distribution of G. intestinalis and C. parvum in Austrian cattle, faecal samples from diarrhoeic calves younger than 180 days of age originating from 70 farms were examined. Of the 177 faecal samples, 27.1% were positive for Giardia cysts (immunofluorescence microscopy) and 55.4% for Cryptosporidium oocysts (phase-contrast microscopy). Positive samples were characterized by nested PCR for Giardia, 83.3% (triosephosphate isomerase; tpi) and 89.6% (β-giardin; bg) were positive, while the Cryptosporidium nested PCR returned 92.5% (60-kDa glycoprotein) positive results. Sequence analysis revealed one assemblage A-positive sample and 30 (bg) respectively 29 (tpi) assemblage E-positive samples for G. intestinalis. For C. parvum four subtypes within the IIa family (IIaA15G2R1, n = 29; IIaA19G2R2, n = 3; IIaA21G2R1, n = 2; IIaA14G1R1, n = 1) could be differentiated. Validation of two immunochromatographic point-of-care tests resulted in a sensitivity of 29.2% and 77.6%; a specificity of 98.4% and 91.1% for the detection of Giardia intestinalis and Cryptosporidium parvum, respectively. Results confirm the widespread occurrence of both protozoa in diarrhoeic calves in Austria.  相似文献   

6.
A study was conducted to investigate the presence of Cryptosporidium and Giardia in Antarctic marine mammals. A total of 270 faecal samples from different species of pinnipeds from different locations in the South Shetland Islands and Antarctic Peninsula were analysed by immunofluorescence microscopy and PCR. Cryptosporidium was detected by PCR in three samples from Southern elephant seals (Mirounga leonina) and 2 Weddell seals (Leptonychotes weddellii). However, no oocysts were observed in any of the samples by immunofluorescence microscopy. Molecular characterisation of the isolates, using the 18S rDNA, the HSP70 and the COWP loci, revealed the presence of a Cryptosporidium sp., previously reported from an Antarctic Southern elephant seal, in the elephant seals and a novel genotype in Weddell seals. Giardia could not be detected in any of the samples analysed.  相似文献   

7.
Cryptosporidium oocysts were found in 43 out of 77 calves from two farms in Iwate Prefecture and nine farms on Tanegashima Island, Kagoshima Prefecture, Japan. The DNA fragments of 18S ribosomal RNA (18S rRNA) gene were amplified by a nested PCR from 43 oocyst-positive as well as one oocyst-negative samples. All of them were precisely identified as C. parvum by analyzing the nucleotide sequences of the 18S rRNA gene. C. parvum oocyst-positive calves ranged in age from 6 to 13 days old and significantly have watery diarrhea (P<0.05). Sequences of the gene encoding the 60-kDa glycoprotein (GP60) in 43 Cryptosporidium oocyst-positive samples were identical to that of the zoonotic IIaA15G2R1 subtype. We therefore suggest that calves could be potential sources of C. parvum infections in humans.  相似文献   

8.
This study was undertaken to investigate the occurrence and public health significance of Cryptosporidium species/genotypes and subtypes in a newborn lambs. A total of 175 diarrheic fecal samples from lambs (younger than 21 days) were collected in seven sheep flocks located in western Romania, and were microscopically examined for the presence of Cryptosporidium oocysts after staining with modified Ziehl–Neelsen technique. Twenty-four (13.7%) fecal samples were tested Cryptosporidium positive by microscopy and were subjected for molecular characterization. All positive samples were successfully amplified through a nested polymerase chain reaction (PCR) of the small subunit (SSU) rRNA gene (18S). Cryptosporidium species were determined by restriction fragment length polymorphism (RFLP) analysis of the secondary PCR products using the conventional SspI and VspI restriction enzymes. The identified species were: Cryptosporidium parvum (20/24), C. ubiquitum (2/24) and C. xiaoi (2/24), respectively. PCR-RFLP results for C. ubiquitum and C. xiaoi isolates were confirmed by DNA sequencing. Subsequently, subtyping of seven randomly selected C. parvum isolates, based on sequence analysis of the GP60 gene, revealed the presence of five different subtypes (IIaA17G1R1, IIaA16G1R1, IIdA20G1, IIdA24G1 and IIdA22G2R1) belonging in two zoonotic subtype families (IIa and IId). These findings may suggest the potential role of the newborn lambs as a source for human cryptosporidiosis. This is the first published report about the presence of C. ubiquitum and C. xiaoi in lambs from Romania.  相似文献   

9.
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 < 500 m from the barn. Prevalence was determined by direct immunofluorescence microscopy, while genotyping and species determination were performed by nested-PCR and DNA sequencing. Giardia was detected in 42% (95% CI: 38-46%) of fecal samples from 100% farms while Cryptosporidium was detected in 17% (95% CI: 14-19%) of fecal samples from 80% of farms. The most predominant Giardia assemblage isolated was the livestock specific assemblage E (89%). The zoonotic assemblages A and B were found in 4 and 7% of the Giardia isolates that were genotyped, respectively. The Giardia assemblages were detected equally between the cows and calves examined. Overall, the most common Cryptosporidium species detected in this study was Cryptosporidium andersoni (49%), predominantly found in cattle >6 mo of age, while most Cryptosporidium bovis and Cryptosporidium pestis (previously Cryptosporidium parvum ‘bovine genotype’) isolates were detected in calves ≤ 6 mo of age. All Cryptosporidium ryanae isolates (four) were found in calves. Giardia cysts and Cryptosporidium oocysts were detected in 14 and 93% of surface water samples of 14 farms, respectively. Cryptosporidium oocysts were detected in three (15%) ground water samples of 20 farms. One Cryptosporidium-positive water sample, which was the only surface water sample amenable to genotyping, contained C. parvum. The farm-level risk factors investigated in this study, age of animals and location of the farm, were not associated with the risk of infection in cattle with either Cryptosporidium spp. or Giardia duodenalis.We conclude that beef cattle are a potential reservoir of Cryptosporidium spp. and G. duodenalis that could contaminate source water. There is the possibility of further transmission to humans on PEI if the source water is not properly treated prior to consumption.  相似文献   

10.
Fecal samples of 2,056 dairy cattle from 14 farms were collected in three geographical regions of China and stained using a modified acid-fast staining technique to identify Cryptosporidium oocysts. A total of 387 (18.82%) positive samples were identified and further analyzed by polymerase chain reaction (PCR) using primers designed to amplify DNA fragments from the small subunit ribosomal RNA. The PCR products were sequenced and the sequences were deposited in the GenBank database under accession numbers EU369377-84 and GU070730-33. Phylogenetic analysis was performed and a distances matrix generated from these sequences confirmed the existence of Cryptosporidium (C.) parvum ''mouse'' genotype, C. bovis, C. andersoni, C. hominis, and C. serpentis in cattle. These results represent the first report on the prevalence and genetic identification of Cryptosporidium species, and may contribute to a better understanding of the epidemiology of Cryptosporidium in cattle in China.  相似文献   

11.
An epidemiological study was carried out in natural water supplies of Hokkaido, one of the largest dairy prefectures in Japan. To investigate the prevalence of Cryptosporidium parvum (C. parvum) oocysts water samples were collected from three rivers in the eastern area of Hokkaido from August 1999 to October 2001, and C. parvum oocysts were collected and purified by the ferric sulfate flocculation method. The oocysts were detected using the immunofluorescent assay test (IFAT) and 4', 6-diamidino-2-phenylindole (DAPI) staining. The seasonal change in the number of oocysts detected was observed. Oocysts increased in numbers from the late summer to the early autumn (from August to November), thereafter, they exhibited a trend to decrease until December, when no oocysts could be detected. The maximum number of oocysts detected in the three rivers was 3.50, 5.00 and 3.33 oocysts/l, respectively. The oocyst density in river water changed in relation to the season in 1999, 2000 and 2001. This report first cleared up the seasonal changes in C. parvum oocysts number in river water.  相似文献   

12.
利用从南宁市郊养鸡场球虫病鸡粪便中收集的球虫混合种卵囊感染小鸡,再应用单卵囊分离感染技术,从感染鸡盲肠中收集的卵囊分离纯化获得1株纯种球虫,经鸡体传代增殖,对该虫株的卵囊大小和卵形指数、潜在期、排卵高峰期、最短孢子化时间、寄生部位、致病性等指标进行观察和测定。结果测得该虫株卵囊的平均大小为(25.743±1.94126)μm×(21.4±1.85985)μm,平均卵型指数为1.2067±0.07;潜在期为140 h;其排卵囊峰期在第6～9天,最高峰在第7天;最短孢子化时间为19 h;寄生部位在盲肠;对两周龄的艾维茵鸡,当使用5×104的孢子化卵囊感染剂量时死亡率为7.5%。根据这些测定和观察到的指标综合鉴定该分离株球虫为柔嫩艾美耳球虫,并命名为柔嫩艾美耳球虫广西南宁株(Eimeria.tenella-GXNN),该研究结果为进一步研究本地区鸡球虫病的药物治疗和免疫预防等奠定了基础。  相似文献   

13.
This study aimed to determine the prevalence and species of Cryptosporidium among HIV/AIDS patients in southwest of Iran. Two hundred fifty faecal samples from HIV patients were examined for the presence of Cryptosporidium oocysts using a conventional coproscopic approach. Such oocysts were detected in 18 (7.2%) out of 250 faecal samples. Genomic DNAs from 250 samples were then subjected to a nested-PCR-RFLP technique targeting different loci of 18S rRNA gene for species identification. Out of 250 samples, 27 (10.8%) were positive for different Cryptosporidium spp; Restriction patterns resulting from the digestion of the nested amplicon with restriction endonucleases VspI and SspI showed that C. parvum (70.38%) was the most prevalent species, followed by C. hominis (25.92%) and C. meleagridis (3.7%), respectively. The mean CD4+ T-cell count was 215 cells/μL. There was a strong association between cryptosporidiosis and CD4+ T-cell count (P = 0.000) with the highest prevalence recorded among patients with CD4+ T-cell count < 200 cells/μL. This confirms that there is a low opportunity for this parasite to get established as the patients CD4+ T-cell count increases. Also HIV infection increased the risk of having Cryptosporidium. Our epidemiological findings are useful for any preventive intervention to control disease diffusion.  相似文献   

14.
Little is known about the diversity and public health significance of Cryptosporidium species in water buffaloes. In this study, we examined the distribution of Cryptosporidium spp. in water buffalo calves in Egypt. Rectal fecal specimens from 179 calves and 359 adults were screened microscopically for Cryptosporidium oocysts using modified Ziehl–Neelsen stain. Cryptosporidium spp. in 17 microscopy-positive specimens from calves were genotyped by DNA sequence analysis of the small-subunit rRNA gene, and Cryptosporidium parvum was subtyped by sequence analysis of the 60 kDa glycoprotein gene. Cryptosporidium ryanae was found in 10 specimens and C. parvum in 7 specimens, with the former belonging to the newly identified C. ryanae buffalo variant and the latter belonging to the subtypes IIdA20G1 (in 5 specimens) and IIaA15G1R1 (in 2 specimens). The prevailing occurrence of C. ryanae and the subtype family IId of C. parvum and the absence of C. bovis and C. andersoni represent some features of Cryptosporidium transmission in water buffaloes in Egypt.  相似文献   

15.
Eimeria alabamensis infections were established in calves 5 to 6 weeks of age by adminestering 10 million, 80 million, or 100 million sporulated oocysts. The prepatent period was 6 to 8 days (mean 6.6). Oocyst discharges usually lasted for 2 to 3 days although a few calves passed oocysts throughout the rest of the 3-week observation period. Calves with oocyst discharge exceeding 1 million oocysts per g of feces had a moderate diarrhea at the time of peak oocyst discharge. No other clinical signs were observed in any of the infected calves. Reinoculations with 100 million sporulated oocysts given 3 weeks after the initial inoculations of 10 million or 80 million oocysts resulted in infections characterized by greatly reduced oocyst discharges. Sporulated oocysts of E. alabamensis were 16 to 24 μ by 12 to 16 μ and were usually ovoid. The oocyst wals consisted of two layers. Sporocysts were elongate-ellipsoid, had a distinct Stieda body, and were 10 to 12 μ by 4 to 6 μ. Completely sporulated oocysts were first observed after 5 days at 25 °C, and most were sporulated after 8 days. Oocysts did not sporulate at 4 °C, 33 °C, and 37 °C.  相似文献   

16.
A total of 413 pig faecal samples were collected from pre-weaners (119), starters (131), pre-growers (123) and sows (40) from a farm with a closed breeding system segmented into two breeding complexes and a growing complex in the region of Vysočina, Czech Republic and screened for the presence of Cryptosporidium using staining methods and genotyping (SSU rRNA). Cryptosporidium oocysts were detected by microscopy in the faeces of 21.1% of the samples (87/413). Sequence analyses and RFLP identified C. suis in 44, Cryptosporidium pig genotype II in 23 and C. muris in 2 samples. No mixed infections were found.Pigs under 7 weeks of age were infected with C. suis only. Cryptosporidium pig genotype II was found in animals from 7 weeks of age. No relationship was found between diarrhoea and any Cryptosporidium infection in any of the different age groups (P < 0.05). The pre-weaned pigs shed significantly more Cryptosporidium oocysts than older pigs and it was associated with C. suis infection.  相似文献   

17.
Toxoplasma gondii, a ubiquitous parasitic protozoan, is emerging as an aquatic biological pollutant. Infections can result from drinking water contaminated with environmentally resistant oocysts. However, recommendations regarding water treatment for oocyst inactivation have not been established. In this study, the physical method of radiofrequency (RF) power was evaluated for its ability to inactivate T. gondii oocysts in water. Oocysts were exposed to various RF energy levels to induce 50, 55, 60, 70 and 80°C temperatures maintained for 1 min. Post‐treatment oocyst viability was determined by mouse bioassay with serology, immunohistochemistry and in vitro parasite isolation to confirm T. gondii infections in mice. None of the mice inoculated with oocysts treated with RF‐induced temperatures of ≥60°C in an initial experiment became infected; however, there was incomplete oocyst activation in subsequent experiments conducted under similar conditions. These results indicate that T. gondii oocysts may not always be inactivated when exposed to a minimum of 60°C for 1 min. The impact of factors such as water heating time, cooling time and the volume of water treated must be considered when evaluating the efficacy of RF power for oocyst inactivation.  相似文献   

18.
The chicken, which is the host for seven species of Eimeria, typically is infected simultaneously by multiple Eimeria species and the oocysts of coccidia are excreted in the feces. A prerequisite for investigation of individual Eimeria species is to isolate a single oocyst from fecal samples. A novel method for isolating a single Eimeria oocyst from poultry litter using a micromanipulator was developed. This simple method is fast and reliable, and provides direct isolation of a single sporulated oocyst from fecal samples harboring multiple Eimeria species or samples contaminated by other species of parasite.  相似文献   

19.
本试验从南宁市郊区某鸡场感染球虫病的病鸡粪便中收集到混合卵囊,采用改良过的琼脂单卵囊分离法从中分离纯化出2个球虫虫株,并对其中的1个球虫分离株进行了鉴定,鉴定结果为:该株球虫卵囊呈椭圆形或卵圆形,卵囊平均大小为(22.51±0.4790)μm×(15.94±0.5599)μm,平均卵型指数为1.41212±0.06714,裂殖体平均大小为31.33 μm×27.46 μm,潜在期为120 h 50 min,排卵高峰期为感染后第6天,最短孢子化时间为18 h 50 min,寄生部位为小肠中、下段,属中等毒力的球虫虫株。通过将这些测定和观察到的指标与各类文献中所记载的各种鸡艾美耳球虫的特征进行了对比,经过综合分析后,将该分离株球虫鉴定为布氏艾美耳球虫,并且将它命名为布氏艾美耳球虫南宁株,记为Eimeria.brunetti-GXNN。对该虫株的成功分离鉴定,为进一步了解本地球虫虫株的生物学特性,开展鸡球虫病的免疫预防奠定了基础。  相似文献   

20.
Christensen, S. AA. Henriksen: Shedding of oocysts in piglets experimentally infected with Isospora suis. Acta vet scand., 1994, 35, 165-172.–Forty-seven piglets were inoculated with doses of 100 to 50,000 sporulated oocysts of Isospora suis. After 5-7 days oocysts were found in faeces. The patent period extended from 8 to 16 days. The shedding of oocysts showed a cyclic pattern with 2-3 peaks separated by intervals of approximately 5 days. Subpatent periods were often seen between the peaks.The level of oocyst shedding during the initial days of the patent period reflected, to some extent, the inoculation dose. However, a maximum of OPG at the 100,000 level was observed among one or more piglets from all groups, regardless of the inoculation dose. Among the majority of piglets inoculated with more than 100 oocysts, the highest OPG-figures were observed in the first peak of the cyclic pattern. Unlike this, the maximum of OPG was observed in the second peak of the cycle among 6 of the 7 piglets inoculated with 100 oocysts only. The triphasic pattern was most pronounced in the low dosed group.The marked upscaling of oocyst production, as particularly registered in the low dosed groups, seams to explain at least part of the problems met under practical conditions, when trying to eliminate the transmission of oocysts between successive litters in the farrowing boxes.The cyclic excretion pattern and an apparent absence of autoinfections may indicate that the development of I. suis in the host includes several oocyst producing generations descending from the same initial infection.The presence of subpatent periods can probably explain the marked variation in OPG, as they are often recorded when examining faecal samples from piglets, even when the samples are originating from the same litter.  相似文献   

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