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1.
AIM: To investigate the role of free-living animals such as sparrows, rodents and flies as potential reservoirs of Campylobacter spp on a dairy farm, and to assess the genetic diversity among Campylobacter isolates from the farm and an urban source. METHODS: A total of 290 samples (bovine, passerine and rodent faeces, and whole flies) were collected from a large commercial dairy farm in the Manawatu district in New Zealand, and from faeces from urban sparrows in a nearby city. Other samples collected from the dairy farm included five from silage, two from aprons worn by workers during milking, two from workers' boots and two from water in troughs in a paddock. Isolates of thermophilic Campylobacter spp were identified morphologically and phenotypically and further characterised molecularly using pulsed-field gel electrophoresis (PFGE) and the restriction enzyme SmaI. RESULTS: Campylobacter jejuni was the only Campylobacter species isolated from all samples. The highest prevalence was found in faeces from dairy cows (54%), followed by faeces from sparrows from the urban area (40%) and the farm (38%), and from rodents (11%) and whole flies (9%). Other samples from the farm environment such as silage, trough water, and workers' aprons and boots were also positive for C. jejuni. Of the 22 restriction patterns obtained, seven were common to more than one source. CONCLUSIONS: Cattle, sparrows, rodents and flies are potential reservoirs of C. jejuni on dairy farms. Identical clones of C. jejuni carried by cattle, sparrows, flies and rodents probably indicate a common source of infection. The high level of asymptomatic carriage of C. jejuni by healthy dairy cows could be sufficient to maintain infections within the dairy farm surroundings via environmental contamination.  相似文献   

2.
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 10(6) 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   

3.
Acute epidemic salmonellosis was investigated in the winter of 1978 in 4 dairy herds in the Waikato district. The outbreaks involved pregnant or recently calved cows. Calves were affected on only one farm. Salmonella bovismorbificans was isolated from the faecal, uterine and environmental samples from the herd most severely affected. In this herd 20, (20%) of the cows died; 10 calves were either born dead or died soon after birth; and 10 cows were culled as unlikely to return to production. S. typhimurium was involved in the outbreaks in the other 3 herds and from one of these farms salmonellae were isolated from the faeces of the 2 farm dogs and from a 12-month-old infant with dysentery. Salmonellae were recovered from all of the clinically ill cows and from 36% of the asymptomatic animals. Salmonellae were widespread on the properties and were isolated from 81% of soil samples; 36% of drain swabs; and from all the pairs of rubber boots worn while collecting samples.  相似文献   

4.
The best combination of primers and the annealing temperature of multiplex PCR for Campylobacter jejuni, Campylobacter coli, and Campylobacter lari were examined. The multiplex PCR was able to detect type strains of the three species. All results of identification of wild strains (30 strains of C. jejuni, 20 strains of C. coli, and 4 strains of C. lari) by the multiplex PCR coincided with those of the conventional biochemical identification tests, suggesting that the multiplex PCR can simultaneously differentiate C. jejuni, C. coli, and C. lari from wild strains of campylobacters easily and rapidly. Campylobacters were detected from sparrow feces by the multiplex PCR and antimicrobial sensitivities of the strains were determined to discuss the role of sparrows in contamination of broilers with C. jejuni. Three out of 13 strains of C. jejuni isolated from sparrow feces showed quinolone resistance. From the frequent use of quinolones for treatment of industrial animals like chickens, pigs, and cows, the three strains of quinolone-resistant C. jejuni in sparrows must have been originated from those industrial animals. Sparrows that have quinolone-resistant C. jejuni were considered to have contacted with industrial animals or thier feed. It may be presumed, on the contrary, that C. jejuni in sparrows could be a potential source of contamination of broilers.  相似文献   

5.
A total of 273 rectal swabs from dairy cows were cultured for Campylobacter jejuni/coli. The isolation rate was 17/72 (24%), 33/106 (31%) and 11/95 (12%) during summer, autumn and winter respectively. Approximately half of the isolates were C. jejuni and the other half C. coli. The isolates recovered from dairy cows were typed by bacterial restriction endonuclease DNA analysis (BRENDA) and compared with those of sheep. Seventeen different BRENDA patterns were produced by the isolates from dairy cows and six from 27 isolates of sheep. Of these 21 different BRENDA patterns only two were common to sheep and cattle.  相似文献   

6.
Several methods were evaluated for collecting fecal and intestinal samples from wild birds found near broiler chicken houses. A few intestinal samples and cloacal swabs were obtained from European starlings and house sparrows. Most of the samples collected consisted of wild bird droppings found on or near the houses. Samples were collected from each of four farms of a broiler integrator during a grow-out cycle: a cycle in the summer for farm A, fall for farm B, and spring, summer, fall, and winter for farms C and D. Of the 25 wild bird intestinal and fecal samples collected from a broiler house on farm A during a grow-out cycle in July-August 1997, 24% were positive for Salmonella spp., 4% for Campylobacter jejuni, and 28% for Clostridium perfringens. Of the nine fecal samples collected from broiler house B in a grow-out cycle in September-November 1997, 33% were positive for Salmonella spp., 11% for C. jejuni, and 22% for C. perfringens. For farms C and D, of the 23 samples collected in March-April 1998, 0 were positive for Salmonella spp., 11% for C. jejuni, and 52% for C. perfringens; of 27 samples collected in June-July 1998, 4% were positive for Salmonella spp., 0 for C. jejuni, and 13% for C. perfringens; of 24 samples collected in August-October 1998, 14% were positive for Salmonella spp., 5% for C. jejuni, and 4% for C. perfringens; of 14 samples collected December 1998-January 1999, 0 were positive for Salmonella, 50% for C. jejuni, and 14% for C. perfringens. The incidence of these bacterial enteropathogens in wild birds near the broiler chicken houses suggests that wild birds that gain entry to poultry grow-out houses have the potential to transmit these pathogens to poultry.  相似文献   

7.
Altogether 16 Campylobacter (C.) isolates could be recovered from 65 Herring gulls: 5 x C. laridis, 2 x C. jejuni biovar 1, 4 x C. jejuni biovar 2 and 5 x C. coli. Campylobacter spp. were isolated from 15 out of 51 samples from Kittiwakes: 2 x C. jejuni biovar 1 and 13 x C. laridis. All C. coli isolates grew on agar containing 1.5% NaCl. Two Campylobacter isolates from 50 House sparrows differed from all other isolates by a distinct beta-hemolysis and other phenotypic characteristics and could not be associated with a certain Campylobacter species. Epidemiological aspects and the possible role of the examined birds as a source of infection for man and domestic animals are discussed.  相似文献   

8.
Bile samples were collected from 477 Iowa dairy cows and were cultured for thermophilic campylobacters. The prevalence of thermophilic campylobacters in the bile was 15.5%. Campylobacter jejuni and C coli from dairy cattle, chickens, pigs, sheep, and human beings were serotyped to develop host-species profiles. Human and cattle serologic profiles were the most similar, and human and chicken profiles shared several similarities. Epidemiologic data from 168 human cases of campylobacteriosis indicated that 23% of the cases were associated with consumption of unpasteurized milk.  相似文献   

9.
OBJECTIVE: To describe antimicrobial susceptibility patterns in Campylobacter spp isolated from dairy cattle and farms managed organically and conventionally in the midwestern and northeastern United States. DESIGN: Longitudinal study. SAMPLE POPULATION: 128 farms. PROCEDURE: Samples and data were collected every 2 months from August 2000 to October 2001. Fecal samples were collected from calves and cows. Milk samples were obtained from the bulk tank and milk line filters. Environmental samples were obtained from a water source, feed bunks of lactating cows, and cattle housing areas. Campylobacter identification and antimicrobial susceptibility testing were performed at a central laboratory by use of microbroth dilution with 2 customized antimicrobial susceptibility panels. RESULTS: 460 and 1,570 Campylobacter isolates were obtained from organic and conventional dairy farms, respectively. Most isolates from both farm types were susceptible to most antimicrobial agents tested, and antimicrobial susceptibility of conventional dairy isolates was decreased, compared with organic dairy isolates. Low proportions of isolates resistant to ampicillin (< 10%) and moderate proportions resistant (30% to 60%) to kanamycin, sulfamethoxazole, and tetracycline were observed on both farm types. The proportion of isolates resistant to tetracycline was higher for conventional than organic farms. CONCLUSIONS AND CLINICAL RELEVANCE: Campylobacter isolates from dairy cattle and farms managed organically and conventionally had similar patterns of antimicrobial resistance; the proportion of resistant isolates was higher for conventional than organic farms.  相似文献   

10.
Campylobacter jejuni and C. coli are the most prevalent causes of bacterial diarrhoea in most of the Western World. In Great Britain, the source remains unknown for the majority of cases, though poultry is considered the main source of infection. Molecular typing methods identify cattle as a potential source of a proportion of the non-source-attributed cases, mainly through direct contact, environmental contamination or milk, but little is known about the epidemiology of Campylobacter in cattle. A cross-sectional study was undertaken on young cattle 3-17 months of age on 56 cattle farms in England and Wales to identify association between the presence of C. jejuni and C. coli and farm characteristics and management practices. Campylobacter was detected on 62.5% of the farms and the presence of dairy cows (OR: 3.7, CI(95%): 1.2; 11.7), indoor housing (OR: 4.6, CI(95%): 1.8; 12.0), private water supply (OR: 2.5, CI(95%): 1.2; 5.4), presence of horses (OR: 3.2, CI(95%):1.5; 6.9) and feeding hay (OR: 2.9, CI(95%):1.6; 5.5) were associated with detection. The model's goodness-of-fit was improved when herd size was forced in the model without being statistically significant (p=0.34).  相似文献   

11.
The relationship of 50 Campylobacter strains isolated from aborted ovine foetuses, and the faeces of sheep, cattle and chickens were determined by numerical analysis of electrophoretic (SDS-PAGE) protein profiles. Comparison of protein patterns by numerical methods revealed differences between C. fetus ssp. fetus, C. jejuni, and C. coli strains as well as heterogeneity among isolates from different outbreaks. Isolates from each farm produced a distinct cluster and flocks from different locations were found to be infected with relatively different strains. In most cases, protein patterns of ovine foetal isolates were very similar to those of ovine faecal isolates. Ovine isolates of C. fetus ssp. fetus, C. jejuni and C. coli gave similar protein patterns to the corresponding Campylobacter species isolated from cattle or chicken, on the same farm. Thus, it was concluded that certain protein types of ovine Campylobacter strains were more likely associated with local areas, and Campylobacter strains causing ovine abortions are distributed in the environment more widely than assumed to date.  相似文献   

12.
The occurrence and species distribution of thermophilic Campylobacter was investigated in organic outdoor pigs. An increased exposure of outdoor pigs to C. jejuni from the environment may cause a shift from a normal dominance of C. coli to more C. jejuni, which may imply a concern of reduced food safety. Bacteriological methods for determination of Campylobacter excretion level were combined with colony-blot hybridization and real-time PCR for specific detection of C. jejuni in pigs. Campylobacter was isolated from pigs (n=47), paddock environment (n=126) and wildlife (n=44), identified to species by real-time PCR and sub-typed by serotyping (Penner) and pulse-field gel electrophoresis (PFGE) genotyping. All pigs excreted Campylobacter (10(3)-10(7) CFU g(-1) faeces) from the age of 8-13-weeks old. C. jejuni was found in 29% of pigs in three consecutive trials and always in minority to C. coli (0.3-46%). C. jejuni and C. coli were isolated from 10% and 29% of the environmental samples, respectively, while crow-birds and rats harboured C. jejuni. Individual pigs hosted several strains (up to nine serotypes). The paddock environment was contaminated with C. coli serotypes similar to pig isolates, while most of the C. jejuni serotypes differed. C. jejuni isolates of different origin comprised few similar serotypes, just one identical genotype was common between pigs, environment and birds. In conclusion, the occurrence of C. jejuni varied considerably between the three groups of outdoor pigs. Furthermore, transfer of C. jejuni to the outdoor pigs from the nearby environment was not predominant according to the subtype dissimilarities of the obtained isolates.  相似文献   

13.
In order to assess the survival of lactic acid bacteria (LAB) in whole crop maize silage in the gut of dairy cows, one representative silage sample and three different feces samples were collected from dairy cows on three dairy farms in Hua Bei, China and three dairy farms in Kyushu, Japan. The composition of the bacterial community was examined by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction. Lactobacillus acetotolerans was detected in all bunker‐made maize silage samples, regardless of the dairy farm or sampling region from which they were sourced. A total of eight LAB species were detected in the maize silage samples, of which three (L. acetotolerans, L. pontis and L. casei) appeared to survive digestion. The populations of L. acetotolerans in silage and feces were 106–7 and 103–4 copies/g, respectively, indicating that, even for the LAB species showing potential survival in the gut, competition in this niche may be harsh and the population may substantially decrease during the digestion process. It may be difficult for silage LAB to survive in the gut of silage‐fed dairy cows, because marked decrease in population can take place during the digestion process, even for surviving species.  相似文献   

14.
Campylobacteriosis is the most commonly notified illness in New Zealand. Whilst the importance of commercial poultry in campylobacteriosis is well established, little is known about the possible role of chickens kept at home as a direct animal/faecal contact or consumption exposure pathway. The aim of this study was to determine the prevalence and genetic diversity of Campylobacter spp. in domestic backyard chicken flocks in the Canterbury region of New Zealand. Poultry faecal samples were collected from 35 domestic 'backyard' poultry flocks from urban and rural properties around the Canterbury Region of New Zealand. A total of 291 samples were collected and tested for the presence of thermotolerant Campylobacter spp. and positive isolates were analysed using pulsed-field gel electrophoresis (PFGE) using both SmaI and KpnI enzymes. There was a high prevalence of Campylobacter spp. with 86% of flocks testing positive. Campylobacter jejuni alone, Campylobacter coli alone and both C. jejuni and C. coli were detected in 20 (57%), 2 (6%) and 8 (23%) of the flocks respectively. SmaI/KpnI PFGE analysis identified 50 different genotypes across the 35 flocks. Genotype diversity richness was highest on the lifestyle block and farm properties with 43 different genotypes isolated, whilst urban properties displayed the least richness with 12 genotypes isolated. Rural flocks tended to have more different genotypes in a given flock than urban flocks. Comparison of the genotypes with the PulseNet Aotearoa Campylobacter database showed that 28 of the genotypes had previously been isolated from human cases of campylobacteriosis. Many of these were also indistinguishable from Campylobacter spp. previously isolated from retail chicken. Therefore, contact with backyard poultry or their faecal material is a potential additional infection pathway outside of exposure to the established pathways associated with the consumption of Campylobacter-contaminated commercial meat or foods cross-contaminated from contaminated poultry.  相似文献   

15.
From June 1983 to June 1984, two hundred twenty-five 3- to 30-month-old chickens (hens) on 10 different farms were examined for Campylobacter spp. Watering trays and fly vectors also were examined for Campylobacter spp on 6 of the 10 farms. Campylobacter jejuni was isolated from fecal specimens from 64 hens (28.4%), C coli was isolated from 6 hens (2.7%), and C laridis was isolated from 9 hens (4%). The isolation rate of C jejuni was 6.7% to 46.7% for 9 of the 10 farms. On 2 farms, agglutinin titers greater than or equal to 1:40 against somatic and flagellar antigen of C jejuni were detected in hens from which the bacteria were isolated. Hens having titers greater than or equal to 1:40 against C jejuni or hens from which C jejuni had been isolated often occupied adjacent pens. Campylobacter jejuni was isolated from a watering tray on 1 farm and from fly vectors on 2 farms.  相似文献   

16.
Campylobacter species are among the most frequently identified bacterial causes of human gastroenteritis. Because Campylobacter spp. harbored by cattle can be transmitted to humans, in this study we investigated antimicrobial resistance of thermophilic Campylobacter isolated from cows. Our study included 150 strains of Campylobacter (143 strains of C. jejuni and 7 strains of C. coli) isolated from cows in South-Western Poland. The minimal inhibitory concentration (MIC) to ciprofloxacin, erythromycin, gentamicin and tetracycline were determined using the agar dilution methodology. All strains of C. coli were susceptible to all four drugs studied. The most frequently detected resistance of C. jejuni was to ciprofloxacin (26 strains 18.2%). Resistance to tetracycline was observed in 5 strains (3.5%). All strains of C. jejuni were susceptible to erythromycin and gentamicin.  相似文献   

17.
针对我国粗饲料资源较差以及广泛存在的青贮铡切较长等现实问题,本研究旨在为制定适合于中国饲料资源条件的青贮以及不同生长和泌乳阶段奶牛的TMR分级标准提供基础数据。本试验对北京地区规模化奶牛场的玉米青贮和TMR样品进行颗粒度筛分和常规营养成分测定,并与美国宾州颗粒度分级筛（PSPS）的TMR颗粒度和日粮NDF推荐值进行比较。通过比对发现我国玉米青贮的饲料颗粒度普遍偏大,第一层筛网上的饲料比例远超过宾州筛3%～5%的推荐值。新产牛和高产牛TMR样品位于第一层筛网上的饲料比例绝大多数超过了8%,第二层筛网上的饲料比例比美国推荐值要低15%～25%,这可能是由于粗饲料（青贮和干草）颗粒度过长造成的。高产牛和新产牛日粮NDF含量处于35%～42%,基本上在美国宾州筛推荐的中低产奶牛日粮的NDF范围,这与我国的粗饲料资源有限、质量不高、粗饲料铡切长度有关。因而,我国牧场不能照搬美国宾州筛的TMR分级标准,而应根据我国粗饲料的国情,制订适合于中国饲料资源条件的青贮与不同生长和泌乳阶段奶牛的TMR分级标准。  相似文献   

18.
The objectives of this study were to identify, at species level, thermophilic campylobacters isolated from clinically healthy sheep by a multiplex polymerase chain reaction (mPCR). The heterogeneity among Campylobacter jejuni and C. coli isolates was also investigated using a restriction fragment length polymorphism (RFLP) analysis of the flagellin (flaA) gene. Samples of intestinal contents, gall bladders and faeces were collected from 610 healthy sheep. While gall bladder samples were plated directly onto Preston agar, an enrichment stage was applied for intestinal and faecal samples. Of the 610 samples, 302 (49.5%) were positive for Campylobacter spp. Using a mPCR assay for species identification, 103 (34.1%) were positive with C. jejuni-specific primers, while 100 (33.1%) were positive with C. coli-specific primers. Additionally, 16 (11.9%) of the intestinal content samples were positive for both species by mPCR. All the isolates identified as C. jejuni and C. coli were successfully subtyped by flaA typing. Of 203 isolates tested, 48 different flaA types were found. Twenty-six flaA types were identified among C. jejuni isolates and the remaining 22 from C. coli isolates.  相似文献   

19.
Tissue samples from 27 casualty adult dairy cattle slaughtered on farms and 32 'normal' cull dairy cattle were analysed microbiologically for total viable counts (tvc), Enterobacteriaceae, Escherichia coli o157, Salmonella enterica and Campylobacter species. Overall the counts of Enterobacteriaceae and tvc were higher in the animals slaughtered on farms, particularly in the spleen. One 'normal' animal yielded E coli O157, and one yielded Campylobacter jejuni, and eight of the cattle slaughtered on farms yielded C jejuni and five yielded S enterica.  相似文献   

20.
Campylobacter species are leading agents of human bacterial gastroenteritis and consumption of food of animal origin is a major source of infection. Although pigs are known to frequently exhibit high counts of Campylobacter in their faeces, more information is needed about the dynamics of this excretion. An experimental trial was conducted to evaluate the faecal excretion of Campylobacter by 7-week-old specific pathogen-free piglets inoculated per os with three Campylobacter strains (one C. coli isolated from a pig, one C. coli and one C. jejuni from chickens) alone or simultaneously (5x10(7)CFU/strain). Non-inoculated pigs were housed in adjacent pens. Pigs were monitored for 80 days for clinical signs and by bacteriological analysis of faeces. Pigs inoculated with porcine C. coli or with a mix of the three strains excreted from 10(3) to 10(6)CFU/g of faeces with a slight decrease at the end of the trial. Animals inoculated with poultry C. coli or C. jejuni strain excreted a lower quantity and some of them stopped excreting. At the end of the trial, only C. coli was detected in the faeces of pigs inoculated simultaneously with the three bacteria. Moreover, the transmission of Campylobacter was noticed between pens for the two C. coli strains and all the neighbouring animals became shedders with a level of excretion similar to the inoculated pigs. Intermittence in the Campylobacter excretion was also observed. Finally, our study highlighted a host preference of Campylobacter, namely C. coli seems to have a higher colonization potential for pigs than C. jejuni.  相似文献   

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