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1.
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 Cryptosporidium infection pattern was present in other geographic areas, we genotyped Cryptosporidium specimens collected from two farms in China and India, using specimens from farms in Georgia, USA for comparison. C. bovis was the most common species found in pre- and post-weaned calves in all three areas. In Georgia, the deer-like genotype was found frequently in pre- and post-weaned calves and Cryptosporidium andersoni was found in one post-weaned calf. Both C. bovis and the deer-like genotype were found in the few milking cows examined in Georgia. There were no differences in the small subunit rRNA gene sequences obtained from C. bovis or deer-like genotype among the three areas. One adult yak in China, however, was infected with a species similar to C. bovis, with only three nucleotide mutations in the target gene. All four common bovine Cryptosporidium spp. were differentiated from each other by restriction fragment length polymorphism analysis of PCR products with enzymes SspI and MboII. Thus, both C. bovis and the deer-like genotype are found in all age groups of cattle in diverse geographic areas and host adaptation of C. bovis might have occurred in yaks.  相似文献   

2.
Fifteen dairy farms in seven states on the east coast of the US were each visited on two consecutive years to determinate the prevalence of Cryptosporidium species in pre-weaned (5 days to 2 months) and post-weaned calves (3-11 months), respectively. After each of 971 fecal specimens collected directly from each calf was sieved and subjected to density gradient centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy, and polymerase chain reaction (PCR). For all PCR-positive specimens the 18S rRNA gene of Cryptosporidium was sequenced. Cryptosporidium was identified from all farms. Types of housing appeared to have no influence with regard to prevalence of infection. Of 971 calves, 345 were infected with Cryptosporidium (35.5%), but more pre-weaned calves (253 of 503; 50.3%) than post-weaned calves (92 of 468; 19.7%) were found to be infected. A total of 278 PCR-positive specimens characterized by gene sequencing revealed Cryptosporidium parvum, Cryptosporidium andersoni, and two unnamed Cryptosporidium genotypes Bovine B (AY120911) and deer-like genotype (AY120910). The prevalence of these Cryptosporidium species and genotypes appeared to be age related between pre- and post-weaned calves. C. parvum, the only zoonotic species/genotype, constituted 85% of the Cryptosporidium infections in pre-weaned calves but only 1% of the Cryptosporidium infections in post-weaned calves. These findings clearly demonstrate that earlier reports on the presence and prevalence of C. parvum in post-weaned cattle that were based solely on oocyst morphology must be reassessed using molecular methods to validate species and genotype. This finding also indicates that persons handling or otherwise exposed to calves under 2 months of age are at greater risk of zoonotic infection from Cryptosporidium than the risk of infection from exposure to older calves.  相似文献   

3.
Experimental infections have been performed in several mammals and birds to determine the host's specificity for Cryptosporidium parvum (of human and bovine origin) and for Cryptosporidium meleagridis (isolated from broiler chicken). The C. parvum infection (of human origin) was established also in calves (Bos taurus), lambs (Ovis aries), mice (Mus musculus), and rats (Ratus norvegicus), but not in broiler chickens (Gallus domestica). The C. parvum infection (of bovine origin), was achieved in calves, lambs, dogs (Canis familiaris), cats (Felis domesticus), rabbits (Orytolagus cuniculus), mice, rats, and guinea-pigs (Cavia porcelus) but not in broiler chickens. We have demonstrated that C. meleagridis can produce infection in broiler chickens and in 5 mammalian species (calves, pigs, rabbits, rats, mice) but not in guinea-pigs.  相似文献   

4.
Diarrheic fecal samples from 258 pre-weaned calves (1-30 day-old) from 9 dairy farms located in Banat region, Romania, were microscopically examined for the presence of Cryptosporidium oocysts. Overall, 65 (25%) samples were found positive. A higher percent of infection was recorded in calves aged between 8 and 14 days compared with other age categories (1-7, 8-14, 15-21 and 22-30 days; p<0.05). Genetic characterization was carried out on all Cryptosporidium-positive samples. After DNA extraction, Cryptosporidium species were determined by a nested PCR of the small subunit rRNA gene (18S) followed by RFLP analysis with SspI, VspI and MboII restriction enzymes. The restriction patterns showed that animals were infected with Cryptosporidium parvum. Subsequently, subtyping of 13 C. parvum isolates, based on sequence analysis of the 60 kDa glycoprotein (GP60) gene, showed 2 subtypes (IIaA15G2R1 and IIaA16G1R1) belonging to the subtype family IIa. This is the first molecular study of bovine Cryptosporidium infection in Romania.  相似文献   

5.
The prevalence of Cryptosporidium species in 1-2-year-old heifers was determined for 571 animals on 14 dairy farms in seven states on the East Coast of the United States. A fecal specimen collected directly from each heifer was processed to concentrate oocysts that were then examined by polymerase chain reaction (PCR). For every PCR-positive specimen the 18S rRNA gene of Cryptosporidium was sequenced. Cryptosporidium was identified by PCR from heifers on 13 of 14 farms. On all except four farms groups of heifers were housed in a barn or in large covered pens. Others were pastured. From many of the same farms an earlier study reported that 41% of 393 pre-weaned calves and 26.2% of 447 post-weaned calves were infected. In the present study, 11.9% of 571 heifers were infected with Cryptosporidium, 0.7% with Cryptosporidium parvum, the zoonotic species. Of 68 PCR-positive specimens characterized by gene sequencing 1, 4, 10, 24, and 29 calves were infected with Cryptosporidium suis, Cryptosporidium parvum, Cryptosporidium deer-like genotype, Cryptosporidium bovis, and Cryptosporidium andersoni, respectively. These findings demonstrate a lower prevalence of infection in 1-2-year-old dairy cattle than in younger cattle as well as a change in the diversity of species present. Consequently, the risk of humans acquiring infection with C. parvum from exposure to feces from yearling and older cattle appears much lower than from exposure to pre-weaned calves.  相似文献   

6.
Fecal specimens were collected from 30 calves from birth to 24 months of age at a dairy farm in Maryland to determine the prevalence and age distribution of Cryptosporidium species/genotypes. After centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy and polymerase chain reaction (PCR). Fragments of the SSU-rDNA gene amplified by PCR were purified and PCR products were sequenced. All 30 calves shed Cryptosporidium oocysts at some time during the 24 months of the study. Of 990 specimens, 190 were Cryptosporidium-positive (19.2%). The highest prevalence of infection was at 2 weeks of age when 29 of the 30 calves were excreting oocysts. Prevalence was higher in pre-weaned calves (1-8 weeks of age) (45.8%) than in post-weaned calves (3-12 months of age) (18.5%) and heifers (12-24 months of age) (2.2%). Sequence data for 190 PCR-positive specimens identified: C. parvum, C. bovis, the Cryptosporidium deer-like genotype and C. andersoni, with cumulative prevalences of 100, 80, 60, and 3.3%, respectively. C. parvum constituted 97% of infections in pre-weaned calves but only 4% and 0% of infections in post-weaned calves and heifers, respectively. All C. parvum GP60 nucleotide sequences were subtype IIaA15G2R1.  相似文献   

7.
Data of the prevalence, age-related and housing-dependence of naturally acquired cryptosporidiosis on 11 dairy and 11 beef farms in South Bohemia (Czech Republic) were collected. The farms were visited over four consecutive years (from 2002 to 2005). The prevalence of Cryptosporidium in pre-weaned (animals until second month of age) and post-weaned (animals from the third month of age) calves was determined. A total of 7001 faecal samples were collected, concentrated by Sheather's floatation method and stained by aniline-carbol-methyl violet. All samples were examined by light microscopy. Cryptosporidium parvum and C. andersoni oocysts were differentiated on morphological criteria. Of the 7021 specimens, 1814 (25.8%) were positive for Cryptosporidium oocysts; 561 samples (8%) for C. parvum and 1253 (17.8%) for C. andersoni. Pre-weaned dairy calves had higher infection levels of C. parvum than pre-weaned beef calves. The prevalence of C. parvum ranged from 1.4 to 56.5% on dairy farms. Only three cases of C. parvum oocysts shedding in pre-weaned calves on beef farms were found. Only one case of C. andersoni infection in pre-weaned calves was detected and no infections of C. parvum in post-weaned calves were found. The prevalence of C. andersoni reached 35.5% on dairy farms and 61.7% on beef farms. Calves that were on pasture all year long, had a lower probability of C. andersoni infection than those calves kept in a cowshed during the winter season.  相似文献   

8.
A study was undertaken to determine the prevalence of Giardia infections in dairy calves and to compare Giardia and Cryptosporidium infections in calves of different ages. Fresh fecal samples were collected from 386 male and female Holstein calves (newborn to 24 wk) in 20 dairies located in the lower Fraser river valley area of British Columbia. Giardia intestinalis, Cryptosporidium parvum, and Cryptosporidium muris were enumerated in each sample after concentration by sucrose gradient centrifugation and immunofluorescent staining. Giardia was identified at all farm locations. The overall prevalence of Giardia in calves was 73% with a geometric mean cyst count of 1180 cysts per gram of feces (CI, 41 to 5014). Cryptosporidium parvum and C. muris were identified in 80% and 40% of the farms, respectively. The prevalence of C. parvum was 59%, and the geometric mean for oocysts was 457 oocysts per gram of feces (CI, 18 to 160). The prevalence of C. muris was only 2% and the mean oocyst counts were 54 oocysts per gram of feces. Giardiasis was not age dependent, and approximately 80% of the calves from 2 to 24 wk were infected. In contrast, C. parvum infections were predominant in calves 2 to 4 wk, while C. muris was demonstrated in calves older than 4 wk. Fourty-seven percent of calves with diarrhea had high numbers of Giardia cysts in their feces. Giardia infections are highly prevalent in dairy calves and should be considered in animals with diarrhea or failure to thrive.  相似文献   

9.
Despite numerous molecular epidemiologic studies of cryptosporidiosis in dairy cattle in industrialized countries, there are very few studies on the diversity and public health significance of Cryptosporidium species in native cattle in developing countries. In this study, a polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the small-subunit (SSU) rRNA gene was used to detect and identify Cryptosporidium spp. in 194 fecal specimens from 2 to 365 days old calves in 20 White Fulani and Sokoto Gudali herds in Nigeria. Thirty one (16.0%) of the specimens were positive for Cryptosporidium. Restriction digestion of the PCR products showed the presence of Cryptosporidium bovis (7.2%), Cryptosporidium ryanae (4.1%), Cryptosporidium andersoni (2.5%), and concurrent occurrence of C. bovis and C. ryanae (1.5%), and C. bovis and C. andersoni (0.5%). There were no significant differences (p>0.05) in Cryptosporidium infection rates by sex, herd location, management system, breed of calves, or fecal consistency. However, calves 180 days or younger had a higher infection rate of Cryptosporidium than older calves (p=0.034). Likewise, younger calves also had higher occurrence of C. bovis and C. ryanae (p=0.022). The absence of zoonotic Cryptosporidium parvum in the calves studied suggests that native breeds of cattle may not be important in the transmission of human cryptosporidiosis in Kaduna State, Nigeria.  相似文献   

10.
ABSTRACT: Feces from 142 animals were collected on 15 farms in the region of Brittany, France. Each sample was directly collected from the rectum of the animal and identified with the ear tag number. Animals were sampled three times, at 5, 15 and 22 weeks of age. After DNA extraction from stool samples, nested PCR was performed to amplify partial 18S-rDNA and 60 kDa glycoprotein genes of Cryptosporidium. The parasite was detected on all farms. One hundred out of 142 calves (70.4%) were found to be parasitized by Cryptosporidium. Amplified fragments were sequenced for Cryptosporidium species identification and revealed the presence of C. parvum (43.8%), C. ryanae (28.5%), and C. bovis (27%). One animal was infected with Cryptosporidium ubiquitum. The prevalence of these species was related to the age of the animal. C. parvum caused 86.7% of Cryptosporidium infections in 5-week-old calves but only 1.7% in 15-week-old animals. The analysis of the results showed that animals could be infected successively by C. parvum, C. ryanae, and C. bovis for the study period. C. parvum gp60 genotyping identifies 6 IIa subtypes of which 74.5% were represented by IIaA15G2R1. This work confirms previous studies in other countries showing that zoonotic C. parvum is the dominant species seen in young calves.  相似文献   

11.
Dung samples were collected from dairy calves of south Indian states viz., Andhra Pradesh, Karnataka, Kerala, Tamil Nadu and union territory, Puducherry and are subjected to nested polymerase chain reaction (PCR) targeting 18S rRNA gene for detection of Cryptosporidium infection. Of the 459 dung samples screened 182 were found positive with a prevalence of 39.65%. Highest prevalence of Cryptosporidium was observed in Puducherry (86.67%) and lowest in Kerala (17.65%). Genotyping by PCR-restriction fragment length polymorphism (RFLP) and sequence analysis revealed the presence of all the four major Cryptosporidium species of cattle viz., Cryptosporidium andersoni, Cryptosporidium ryanae, Cryptosporidium parvum and Cryptosporidium bovis. C. andersoni was widely distributed in calves of Tamil Nadu, Karnataka and Puducherry whereas in Andhra Pradesh C. ryanae was the major species. Of the 64 samples subjected to PCR-RFLP, 39 (60.94%) could be classified as C. andersoni, 18 (28.13%) as C. ryanae, 4 (6.25%) as C. parvum and 3 (4.69%) were confirmed as C. bovis. The results were also confirmed by sequencing of 19 Cryptosporidium DNA samples.  相似文献   

12.
以隐孢子虫(Cryptosporidium spp.)18S rRNA为靶基因,通过巢氏PCR检测发现在采集的101份新鲜粪便样品中18份样本为阳性。不同地区羊场的隐孢子虫感染率分别为：李集镇36%(18/50),新安镇0%(0/30)、堆沟港镇0%(0/21)未检出隐孢子虫。但通过对4羊场的分析发现,有2个羊场(50%)为隐孢子虫感染阳性,且不同的羊场感染率差异显著,因此单纯的以地区来评价隐孢子虫的感染率,是值得商榷的。山羊隐孢子虫的感染率为33.3%,湖羊隐孢子虫的感染率为2%。2～6月龄的育肥羊隐孢子虫的感染率为36%,6～10月龄的育成羊(0%)。对检测为阳性的样品进行了隐孢子虫18S rRNA基因片段序列分析,发现18个样品全部为肖氏隐孢子虫(Cryptosporidium xiaoi),不存在泛在隐孢子虫(Cryptosporidium ubiquitum)。在检测隐孢子虫感染阳性的1个山羊场和1个羊湖羊场均存在肖氏隐孢子虫感染,不存在泛在隐孢子虫,更未发现肖氏隐孢子虫和泛在隐孢子虫的混合感染。目前的数据提示肖氏隐孢子虫对2～6月龄山羊(33.3%)和湖羊(2%)具有更高的...  相似文献   

13.
A total of 145 capybara (Hydrochoerus hydrochaeris) fecal samples from the state of S?o 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 glycoprotein gene fragments showed that for both genes all Cryptosporidium isolates from capybara were respectively 100% genetically similar to a bovine isolate of C. parvum and to C. parvum subtype IIaA15G2R1. To the best of our knowledge this is the first report of Cryptosporidium infection in this rodent. The finding of zoonotic C. parvum infection in a semi-aquatic mammal that inhabits anthroponotic habitats raises the concern that human water supplies may be contaminated with zoonotic Cryptosporidium oocysts from wildlife.  相似文献   

14.
Recent studies have identified the novel, host adapted Cryptosporidium bovis and the deer-like genotype in dairy cattle from farms in the United States, China, India and Europe. This novel species and genotype appear to be more prevalent in older, post-weaned dairy cattle than previously thought. However, little information is available on their prevalence in beef cow-calf operations. In the present study, we determined the prevalence of Cryptosporidium species in 98 calves (6-8 months old) and 114 cows (>2 years old) in seven beef cow-calf herds in western North Dakota. DNA was extracted from fecal samples and Cryptosporidium spp. were identified by amplification of the 18S rRNA gene followed by sequencing or RFLP analysis. All seven herds tested positive for Cryptosporidium. Overall, 43/212 (20.3%) animals were positive. Only five of these positives were from cows. C. bovis, the deer-like genotype and C. andersoni were identified in 9.4, 6.6 and 1.4% of animals sampled, respectively. C. parvum was not identified in any of the positive samples. C. bovis, the deer-like genotype and C. andersoni were detected in 6/7, 5/7 and 2/7 herds, respectively. C. bovis and the deer-like genotype were primarily detected in calves, while C. andersoni was only detected in cows. Six isolates could not be typed. These results show a relatively high prevalence of C. bovis and the deer-like genotype in 6-8-month-old beef calves compared to cows older than 2 years in the seven herds studied.  相似文献   

15.
Fecal samples from 291 calves and 176 adult cattle in Northern Portugal were screened for Cryptosporidium and Giardia using a formalin-ethyl acetate concentration method. Acid-fast staining techniques for Cryptosporidium oocyst identification and direct microscopic observation of fecal smears for Giardia cyst identification were performed so as immunofluorescence microscopy examination. Polymerase chain reaction methods were employed to determine the genotype of each isolate. Molecular characterization was performed using amplification and sequencing of the hsp70 and 18SrRNA genes of Cryptosporidium and beta-giardin gene and glutamate dehydrogenase for assemblage determination of Giardia duodenalis. Seventy-four out of 291 calves (25.4%) and 8 out of 176 adult bovines (4.5%) were positive for Cryptosporidium. Forty-one out of 291 calf samples (14.1%) and 1 out of 176 adults samples (0.57%) were positive for Giardia. From the Cryptosporidium positive samples we obtained 63 isolates from calves samples and 7 isolates from adult samples. Additionally, Giardia was isolated in 13 out of 41 positive samples from calves and it was also possible to isolate Giardia from the positive adult sample. Molecular characterization of the Cryptosporidium and Giardia isolates showed us that C. parvum and G. duodenalis assemblage E were the prevalent species. C. parvum may infect humans, representing a potential public health risk. On the other hand, the assemblages B and A2 of Giardia, previously described in humans, were here identified in cattle. Further studies will be needed for determine the importance of cattle as carrier of zoonotic assemblages of G. duodenalis.  相似文献   

16.
OBJECTIVE: To determine duration of infection and association of infection with diarrhea for dairy calves with naturally acquired cryptosporidiosis and giardiosis. DESIGN: Cohort study. ANIMALS: 20 Holstein calves on a single dairy farm. PROCEDURE: Fecal samples were collected 3 times/wk for the first 45 days after birth, then weekly until calves were 120 days old and examined for Giardia duodenalis cysts and Cryptosporidium parvum oocysts. Calves were monitored for diarrhea during the first 45 days after birth; during each episode of diarrhea, fecal samples were examined for parasitic, bacterial, and viral pathogens. RESULTS: All 20 calves shed Giardia cysts and Cryptosporidium oocysts at some time during the study. Mean ages at which Giardia cysts and Cryptosporidium oocysts were first detected were 31.5 and 16.3 days, respectively. Mean number of Giardia cysts in feces remained high throughout the study, whereas Cryptosporidium occysts decreased to low or undetectable numbers 2 weeks after infection. Eighteen calves had a total of 38 episodes of diarrhea during the first 45 days after birth. Giardia duodenalis was the only pathogen identified during 6 (16%) episodes, C parvum was the only pathogen identified during 9 (24%) episodes, and G duodenalis and C parvum were identified together during 10 (26%) episodes. CONCLUSIONS: Prevalences of giardiosis and cryptosporidiosis were high in these calves, and both parasites were associated with development of diarrhea. Cryptosporidium parvum was an important pathogen when calves were < 1 month old, but G duodenalis was more important when calves were older. Calves cleared C parvum infections within 2 weeks; however, G duodenalis infections became chronic in these calves.  相似文献   

17.
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 Cryptosporidium species by PCR. The sequence and phylogenetic analysis of 14 isolates indicated that Cryptosporidium parvum was most common (11 isolates) followed by Cryptosporidium deer-like genotype (3 isolates). The present work reports the first data on Cryptosporidium genotyping from cattle in Malaysia.  相似文献   

18.
The significance of Cryptosporidium as a causative agent of diarrhea has been assessed in bovine for a period of 2 years. A total of 940 faecal samples (470 samples in each year) both from diarrhoeic and non-diarrhoeic bovine (0-12 months age) were examined during three different seasons (rainy season, summer and winter). Overall Cryptosporidium was detected in 17.46% and 18.04% cases in first and second year, respectively. Out of 50.21% diarrhoeic and 49.79% non-diarrhoeic cases Cryptosporidium was detected in 26.79% and 8.13% in first year and 27.49% and 8.59% in second year. Year did not have any significant effect on the occurrence of cryptosporidiosis in bovine during this study period. The prevalence of cryptosporidiosis, both in diarrhoeic (61.64%) and non-diarrhoeic (47.22%) cases was highest in 0-1-month age group (P<0.01). Such a high percentage of cryptosporidiosis in clinically asymptomatic animals indicated that the particular age group of animals might be reservoir for the parasite. During this study period highest prevalence was recorded in rainy season (27.55%) followed by summer (16.99%) and winter (8.71%) (P<0.01). A total of 166 positive cases were genotyped. Molecular characterization of bovine cryptosporidiosis has been carried out by PCR-RFLP analysis of SSU rRNA gene and results indicated that Cryptosporidium parvum mainly responsible for diarrhea in bovine in India.  相似文献   

19.
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 mucosa and in the draining lymph nodes of treated calves were similar to those of untreated control calves. However, when rBoIL-12 was subcutaneously administered daily from 2 days before infection to 2 days after infection, a consistent increase of T lymphocytes and an higher expression of interferon-gamma (IFN-gamma) was detected. Again, treatment did not alter the course of infection. Similar results were obtained when rBoIL-12 was administered daily for 4 days beginning 2 days after oral inoculation. These data indicate that although rBoIL-12 stimulated a strong immune response in the gut of neonatal calves, the response was not able to provide protection from challenge inoculation with C. parvum oocysts.  相似文献   

20.
A total of 750 faecal samples of dairy calves at up to 2 months of age kept in various housing systems were screened for Cryptosporidium spp. infection using the aniline-carbol-methyl violet staining method. DNA was extracted from Cryptosporidium positive samples and from 150 randomly selected microscopically negative samples. Nested PCR was performed to amplify the partial SSU rRNA gene of Cryptosporidium that was subsequently digested by SspI, VspI and MboII restriction enzymes to determine the present Cryptosporidium species and genotype. In addition, the samples characterized as Cryptosporidium parvum were subsequently analyzed at the GP60 gene to determine the distribution of zoonotic subtypes. Sequence analyses and RFLP identified C. parvum in 137, Cryptosporidium andersoni in 21 and Cryptosporidium bovis in 3 samples. Neither mixed infections nor Cryptosporidium ryanae was detected. Sequencing of the GP60 gene from C. parvum-positive samples revealed all five subtypes of family IIa (A15G2R1, A16G1R1, A22G1R1, A18G1R1, and A15G1R1). The obvious management-associated distribution of Cryptosporidium spp. was demonstrated. Direct contact with adult animals was found to be a risky factor for C. andersoni and C. bovis infection. IIaA15G2R1 and IIaA16G1R1 were detected as major subtypes, whereas only the IIaA16G1R1 subtype was found in animals kept in boxes. Three of the five detected subtypes were previously associated with human cryptosporidiosis, and moreover, the IIaA15G1R1 subtype, previously reported in humans only, was detected in calves for the first time.  相似文献   

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