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1.
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 young stock and 5 cows in each herd. Clinical observations of sampled animals and environmental status were recorded, and farmers were interviewed about management procedures. Faecal samples were cleaned by sodium chloride flotation and detection of oocysts was made by epifluorescence microscopy. Cryptosporidium parvum-like oocysts were found in 96% of the herds. Prevalence was 52% in calves, 29% in young stock and 5.6% in cows. Three two-day-old calves shed oocysts. Cryptosporidium andersoni was found in seven animals from four different herds. Factors associated with prevalence of shedders among sampled animals in a herd were age at weaning, cleaning of single calf pens, placing of young stock, system for moving young stock, and year of sampling. Factors associated with shedding in calves were age, placing of young stock, routines for moving young stock and time calf stays with the cow. The only significant factor in young stock was age. In cows, number of calves in the herd and type of farming (organic vs. conventional) affected shedding.  相似文献   

2.
Cryptosporidium spp. are common intestinal protozoan parasites that infect a wide range of hosts, including humans and livestock, worldwide. The objective of this study was to determine the prevalence of Cryptosporidium spp. in dairy calves in Prince Edward Island, Canada, and the potential for transmission of this parasite between dairy calves and humans. Fecal samples were collected from 183 dairy calves from 11 farms in Prince Edward Island. The prevalence of Cryptosporidium spp. infections in these animals was determined by examining for the presence of oocysts in the fecal samples, using immunofluorescence microscopy. Molecular characterization was done using a nested-PCR protocol to amplify fragments of the Cryptosporidium heat-shock protein 70 gene, followed by DNA sequencing. Ten calves (6.2%), representing 4 out of 11 farms tested, were positive for Cryptosporidium spp. DNA sequence analysis on five PCR positive samples demonstrated that Cryptosporidium parvum was the only species present in the calves tested, suggesting that there is a potential risk of zoonotic transmission between dairy calves and humans in this region.  相似文献   

3.
AIM: To determine the occurrence of Cryptosporidium parvum oocysts, Campylobacter spp and Salmonella spp in faecal samples taken from newborn dairy calves on 24 dairy farms in the Manawatu region of New Zealand.

METHODS: A cross-sectional study was conducted during the 2002 calving season. Faecal samples were collected from 185 newborn calves from a convenience sample of 24 dairy farms. The samples were tested microscopically for the presence of C. parvum oocysts, and bacteriologically for the presence of Campylobacter spp and Salmonella spp.

RESULTS: Infections with C. parvum were identified in 33/156 (21.2%) calves from 10 farms. More than 106 oocysts/g (OPG) faeces were detected in calves from four farms. Campylobacter spp were isolated from 58/161 (36%) calves from 18 farms; in particular, C. jejuni subsp jejuni was isolated from 11/161 (6.8%) calves from seven farms. Salmonellae were not detected.

CONCLUSIONS: Despite the short and concentrated calving pattern and the long interval between calving seasons characterising most dairy farms in New Zealand, C. parvum is widespread among calves. Campylobacter spp, especially C. jejuni, rapidly colonise the intestinal tract of newborn calves.

RELEVANCE: This study provided an estimate of the ecological impact of newborn dairy calves with regard to the potentially zoonotic enteric pathogens most frequently isolated from human gastrointestinal infections in New Zealand.  相似文献   

4.
Mycoplasma bovis is an important cause of calf pneumonia worldwide. In this study, we examined 140 cattle at slaughter comprising 70 veal calves and 70 beef cattle; 115 animals with pneumonic lesions and 25 without. Lung samples were submitted for bacteriological, histological, and M. bovis-immunohistochemical analyses. Serology for M. bovis was positive in 76% of beef cattle and 100% of veal calves. M. bovis was isolated only from veal calves in 16 out of 64 pneumonic cases. M. bovis was detected by immunohistochemistry in seven bacteriologically positive cases. M. bovis antigen was associated with bronchogenic necrosuppurative or fibrinonecrotizing lesions. Bacteriologically positive and immunohistochemical negative cases were associated with catarrhal bronchointerstitial pneumonia. Results suggest that M. bovis infection may develop into a severe necrosuppurative bronchopneumonia or fibrinonecrotizing pneumonia when associated with a high number of intralesional organisms or, conversely, into a mild catarrhal bronchointerstitial pneumonia when associated with a low number of organisms.  相似文献   

5.
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   

6.
Molecular epidemiology of Cryptosporidium subtypes in cattle in England   总被引：1，自引：0，他引：1  
Samples of Cryptosporidium spp., collected in a cross-sectional study of calves (median age 26 days) from 41 farms in Cheshire, UK, underwent molecular typing. The aim was to determine naturally occurring species/genotypes and to investigate transmission pathways within a local area. Of 60 positive samples, 54 were sequenced at an 18S rRNA locus and 51 were typed at a GP60 locus. C. parvum was identified in 50 samples, three cases were C. bovis and one was Cryptosporidium deer-like genotype. Six GP60 subgenotypes were identified. One subgenotype (IIaA15G2R1) was highly prevalent throughout the study area. A single subgenotype was identified on 20/22 farms. Two subgenotypes were found on 2/22 farms. The spatial scan statistic detected a cluster of subgenotype IIaA15G2R1 comprising seven farms. This suggests local transmission of the parasite between farms. As most of the isolates detected were the potentially zoonotic C. parvum allele IIa, intervention strategies should be considered to reduce the threat to public health. Biosecurity measures may reduce transmission between farms and result in lower levels of environmental contamination.  相似文献   

7.
In this study we have characterized M. bovis isolates from a herd of cattle in Uvalde, Texas in which 52 of the 193 animals selected at random in 1994 from a herd of 331 were caudal fold skin-test positive. Thirty-two of 52 skin-test positive cattle had gross lesions at slaughter, and isolations of M. bovis were made from 29 animals. The herd was comprised of Red Devon cattle purchased between 1978 and 1980 (n = 26) and breeding bulls (n = 3) introduced at later times, and all were tuberculosis test negative at the time of purchase. Other animals were natural additions (offspring) of these cattle. One additional animal, a Holstein present on the ranch at the time of purchase in 1976, was retained to nurse orphaned and weak calves. Using several molecular fingerprinting techniques we have verified a clonal relationship among the M. bovis isolates consistent with infection originating with a single strain. The molecular fingerprint patterns demonstrate the stability of the profiles despite persistence and spread of the organism within the herd for two decades and confirms their use in epidemiological tracing.  相似文献   

8.
The diversity of Cryptosporidium at species, subtype family and subtype level in diarrhoeic children was investigated in four provinces in South Africa. A total of 442 stool samples from children <5 years of age were collected under a large rotavirus surveillance programme and analysed by Ziehl–Neelsen acid‐fast staining. Fifty‐four (12.2%) were positive for Cryptosporidium, of which 25 were genotyped by polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP) and DNA sequence analyses of the 18S rRNA gene. The majority of genotyped specimens were identified as C. hominis (76%), and a high genetic diversity was found with five different C. hominis subtype families (Ia, Ib, Id, Ie and If). Cryptosporidium parvum was found in 20% of the isolates, and three subtype families were identified (IIc, IIe and IIb), with subtype family IIc being the most common. One specimen was identified as C. meleagridis of the subtype family IIId. These results are in accordance with findings from other developing countries and report for the first time the presence in South Africa of C. meleagridis, various subtypes of C. parvum and the subtype family Ie of C. hominis. The results suggest that C. hominis and anthroponotic C. parvum subtypes are the major cause of cryptosporidiosis in South Africa. Further molecular studies are needed to better understand the epidemiology and public health importance of Cryptosporidium in humans in South Africa.  相似文献   

9.
The prevalence of Cryptosporidium species in calves and heifers with relation to diarrhea from several herds was investigated in this study. Fecal samples were collected from 135 and 120 pre-weaned calves and 79 and 130 heifers raised in the Central Anatolia (CAR) and Mediterranean Regions (MR) of Turkey, respectively. A total of 86 post-weaned calves in CAR were also included in the study. For diagnostic comparison, all samples were examined by microscopic examination, SSU rRNA nested PCR and TaqMan real-time PCR for the presence of oocyst and Cryptosporidium DNA. In total, 102 (34.0 %) and 93 (37.2 %) of the examined samples from CAR and MR were found positive for Cryptosporidium DNA with both nested PCR and real-time PCR analyses, respectively with an overall prevalence of 35.5 %. The diagnostic sensitivity and specificity of microscopic examination were determined as 68.7 % and 100.0 % compared to molecular tools, respectively. RFLP and sequence analyses of the SSU rRNA from the PCR products revealed that 138 (70.8 %) out of 195 positive isolates were C. parvum further confirming the species-specific real-time PCR results. Among the remaining 57 (29.2 %) positive isolates, 30 (15.4 %) and 27 (13.8 %) were characterized as C. ryanae and C. bovis, respectively. C. parvum was the dominant species in pre-weaned calves especially with diarrhea while C. bovis and C. ryanae were mostly found in post-weaned calves and heifers. The sequence analyses of the gp60 gene of C. parvum isolates revealed two subtypes (IIaA13G2R1, IIaA14G1R1) belonging to zoonotic family IIa, with IIaA13G2R1 being the most common in diarrheic calves.  相似文献   

10.
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   

11.
The presence of antibodies against Encephalitozoon cuniculi (E. cuniculi) and Encephalitozoon intestinalis (E. intestinalis) was examined in 215 samples from humans and in 488 samples from five different species of domestic and companion animals in Slovakia. The 215 human samples and samples from 90 swine, 123 non-infected cattle (cattle), 24 cattle infected with bovine leukosis virus (BLV-positive cattle), 140 sheep and 111 dogs were examined by the enzyme-linked immunosorbent assay (ELISA). Samples with serum titres 1:200 or higher were considered as positive. Specific anti-E. cuniculi antibodies were found in humans (0.9%), swine (52%), cattle (2%), sheep (9%) and dogs (15%) except for the BLV-positive cattle at the titre of 1:200. The titre of 1:400 was detected only in humans (0.5%). The presence of specific anti-E. intestinalis antibodies at the titre of 1:200 was confirmed in humans (6%), swine (51%), cattle (11%), BLV-positive cattle (13%) and dogs (6%) but not in sheep. The anti-E. intestinalis antibodies reached the 1:400 in humans (1%), swine (4%) and BLV-positive cattle (17%). The presence of specific anti-E. intestinalis antibodies at the titre of 1:600 was observed only in one swine (1%). Significant differences were observed in animals at titres 1:200 and 1:400 (chi-squared test: p < 0.0001) for both pathogens and in humans only for E. cuniculi at the titre of 1:400 (chi-squared test: p < 0.0075).  相似文献   

12.
Signs of severe otitis media in 20% of dairy calves on one farm were associated with Mycoplasma bovis infection, based on isolation from the external ear canal and nares. Affected calves seroconverted to M. bovis and no other significant bacteria were isolated. Infection was considered likely to have originated from cows in the milking herd based on evidence of seroconversion and detection of infection in a milk sample. M. bovis infection should be considered when investigating otitis problems in calves.  相似文献   

13.
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   

14.
Although Cryptosporidium spp. are found throughout the world and in multiple environmental conditions, few data are available that explore the possibility of an association between specific environmental parameters and the species or strain of Cryptosporidium. This study examines the potential association between a particular Cryptosporidium species/strain found in calves and soil provinces in Georgia, USA. Necropsy cases spanning the years 1996-2002 were tested. No significant differences (P=0.962, chi(2) test of homogeneity) between numbers of positive cases were noted among soil provinces. Phylogenetic analysis of the sequences for the PCR products revealed sequence similarity of the products with Cryptosporidium parvum strain C1. Although, clinical Cryptosporidiosis in calves was not found to be affected by soil province and may be caused by a single genotype, other genotypes may be responsible for subclinical infection and warrant further investigation.  相似文献   

15.
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   

16.
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17.
Larval antigen of Hyalomma anatolicum anatolicum, the vector of Theileria annulata, was purified by two-step affinity chromatography using anti-tick gut-specific rabbit IgG and IgG from immunized cattle. The purified antigen showed the presence of a single polypeptide of 37 kDa (GHLAgP) on SDS-PAGE. Two groups (I and II) of naive crossbred calves (Bos taurus × B. indicus) were immunized with 1 mg of GHLAgP in three divided doses. Immunized calves of group I were also infected with a sublethal dose of T. annulata along with a group of non-immunized calves (group III). Animals in groups I, II, III as well a control group (group IV) were challenged with live nymphs of H. a. anatolicum on the 10th day of immunization. There was a significant reduction in the number of emerging adults of 56.9% ± 1.67% in calves of group I (p < 0.01) and 63.09% ± 1.26% in calves of group II (p < 0.001) compared to the controls. The calves of groups I and II showed antibody responses to tick antigen up to day 70 post immunization. Infection with T. annulata was determined in the salivary glands of adult ticks that developed from the nymphs used for challenge infection. In ticks taken from group I calves, there was a 75.0% ± 0.00% infection compared with only 85.0% ± 2.88% infection in ticks taken from calves of group III. Using PCR, a lower infection (83.33% ± 3.33%) was detected in ticks that developed from calves of group I compared with calves from group III (90.00% ± 2.88%). The ground-up tick supernatants (GUTS) of the ticks taken from calves of group III yielded higher infection rate and exhibited higher infectivity titre in in vitro infection assay of bovine mononuclear cells than the GUTS of the ticks taken from calves of group I. The results suggest a partial reduction in growth rate of T. annulata in ticks feeding on calves immunized with GHLAgP.  相似文献   

18.
The commercial LCx amplification assay, usually employed to detect the Myocobacterium tuberculosis complex in respiratory specimens, was evaluated by comparing the results it gave with those obtained using Löwenstein-Jensen solid medium and pathological findings on 55 lymph nodes from cattle with positive and 10 lymph nodes from cattle with negative skin tests for tuberculosis. Fifty-three cultures (51 and 2, respectively) were positive for M. bovis, while the results for the LCx assay and the histological method were positive in 48 (45, 3) and 24 (20, 4) samples, respectively. None of the samples from cattle from certified tuberculosis-free herds were positive by any of the procedures. The results obtained with the LCx assay, compared with the culture procedure, regarded as the gold standard among the diagnostic techniques, gave a specificity of 91.6% and sensitivity of 90.5%. Although the sensitivity of LCx was suboptimal, DNA of M. bovis was detected in 81.8% of the skin test-positive animals. Amplification techniques could provide a rapid and reasonably reliable tool for detecting bovine tuberculosis.  相似文献   

19.
Over 250 individuals fell ill in five outbreaks caused by Cryptosporidium parvum in Finland, October–November 2012. The cases were connected by lunch meals at restaurants in four different cities. In two outbreaks, the same C. parvumIIdA17G1 subtype was found in patients’ stool samples which supports a single source of infection. Frisée salad was the only common food item served at the restaurants, and consumption of lunch salad containing the frisée salad was associated with the illness. Lunch customers who responded that they had eaten lunch salad were three times more likely to have become ill than those who had not answered whether they had eaten the salad or not (RR 2.66; 95% Cl 1.02–6.9, P‐value <0.01). Cryptosporidiosis should be considered as a causal agent in long‐lasting watery diarrhoea combined with abdominal cramps, and clinical samples should be tested for Cryptosporidium at the same time bacteria and viruses are tested. Measures to prevent contamination of ‘ready‐to‐eat vegetables’ with Cryptosporidium oocysts and methods to test frozen food samples should be developed.  相似文献   

20.
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   

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