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1.
We investigated the genotype and serotype diversity of Campylobacter coli and C. jejuni in two parent flocks of adult hens and their offspring over two rotations in order to evaluate the role of hatchery mediated transmission and/or vertical transmission of campylobacters in broiler flocks. In total, 314 C. jejuni and 32 C. coli isolates from parent and broiler flocks and from the surroundings of broiler houses were typed by flagellin gene PCR/RFLP (fla-typing), and selected isolates were also typed by serotyping and macrorestriction profiling using PFGE (MRP/PFGE). The combined typing results showed that the broiler flocks could be colonised by 1-3 different Campylobacter clones and parent flocks could be colonised by 2-6 different clones. C. coli was isolated from up to 36% of birds in one parent flock, whereas only C. jejuni was isolated from broiler flocks. C. jejuni clones from different flocks were clearly discriminated by fla-typing as well as by MRP/PFGE, except for a few cases where individual isolates belonging to two different clones were found to have altered fla-types. Similarly, one C. coli clone showed pronounced fla-type variation. The present results lead to the conclusion that vertical transmission or horizontal transmission via the hatchery are not significant transmission routes of C. jejuni to broiler chickens under Danish conditions. In the cases where more than one Campylobacter clone simultaneously colonised flocks, we found that the different clones coexisted in flocks rather than excluding each other.  相似文献   

2.
The resistance to cecal colonization by Campylobacter jejuni was assessed by challenging three crossbred stocks of commercially available broiler chickens. These three stocks, designated A, B, and C, were related as follows: Offspring from four pedigreed grandparent flocks were used as progenitors. Stock B was derived by cross-breeding grandparent 1 with grandparent 3. Stocks A and C were crossbreeds from grandparents 1 and 2 and grandparents 3 and 4, respectively. Campylobacter jejuni were gavaged into 48-hour-old chicks, using the same levels of challenge dose for each of the different chicken stocks. Six days post-challenge, the birds were sacrificed, and cecal contents were plated onto Campylobacter-selective media. Results from two replicate trials with three isolates of C. jejuni indicated that chicken stock A was colonized in only two of 60 ceca, stock B in six of 60, and stock C in 19 of 60 chicken ceca. Statistical analysis of these data indicate that resistance to cecal colonization by C. jejuni was significantly (P less than 0.05) influenced through chicken host lineage.  相似文献   

3.
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   

4.
Campylobacter jejuni is frequently present in the intestinal tract of commercial broiler chickens, and their drinking water has been proposed to be an initial source of bacteria for newly hatched chicks. We studied three sequential commercial broiler flocks raised in a house from which we had cultured C. jejuni from the nipple waters prior to placement of the first flock. Campylobacter cells were detected by immunofluorescence in the biofilm of the drinking nipples during the weeks when the flock was colonized with C. jejuni but not during weeks when the birds were negative. Campylobacter jejuni was isolated from the drinking water during the growth of the first flock and was present in the birds from all three flocks. Randomly amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR) typing with primer OPA11 indicated that seven distinct strains were present within the broiler house. One strain found in drinking water was similar to a strain found in birds in the second flock; however, RAPD-PCR with primer HLW85 showed that the strains were not identical. These results suggest that although the watering system is a potential source of C. jejuni in broiler flocks, the waterborne strain in this study was not detected in the birds.  相似文献   

5.
Prevalence of Campylobacter jejuni was determined in a selected population of domestic and free-living birds submitted for necropsy to the Louisiana State Veterinary Medical Diagnostic Laboratory. The 445 cases examined included 13 orders of birds and yielded C. jejuni in 45 cases, representing an isolation rate of 10.1%. Prevalence was highest in Galliformes (25.2%), followed by Anseriformes (12.9%) and Columbiformes (8.3%). Only one isolation was made out of 179 Psittaciformes examined. Penner serotypes 1, 2, 4, and 16 were most commonly identified among the C. jejuni isolates. This study emphasizes the importance of Galliformes as reservoirs of C. jejuni. The commonality of these serotypes with isolates derived from humans suggests the zoonotic potential of Galliformes in relation to human campylobacteriosis. The isolation rate of 12.9% in Anseriformes implicates free-living and migratory waterfowl as carriers of C. jejuni. Results confirm that Psittaciformes represent a low risk of C. jejuni infection in humans.  相似文献   

6.
Cecal contents (16 samples/each flock) of broilers derived from 212 flocks were investigated for colonization of Campylobacter from 1995 to 1999 in the southern part of Japan, and the isolates were tested for antimicrobial susceptibilities. C. jejuni-positive flocks numbered 42 (19.8%) and C. coli-positive ones 26 (12.3%); Campylobacter spp. were recovered from 68 flocks (32.1%) in total. MICs of ampicillin, erythromycin (EM), tetracycline, nalidixic acid (NA), norfloxacin (NFLX), and ofloxacin (OFLX) to these 68 Campylobacter isolates were determined. Quinolone-resistant Campylobacter isolates numbered 22 (32.4%). All the isolates except one were cross-resistant to NA, OFLX, and NFLX. A high frequency of quinolone-resistance was found in both C. jejuni and C. coli, whereas a high level of EM-resistance was found in only C. coli strains. All C. jejuni isolates were sensitive to EM.  相似文献   

7.
Campylobacter jejuni frequently colonizes the avian intestine. Recent evidence suggests that this organism can also colonize the oviduct of laying hens. However, the source and role of this colonization are unknown. Isolates from the ceca, cloacae, and oviducts of 11 laying hens in three intensive egg-producing flocks were genotyped by Fla typing with the restriction fragment length polymorphism of the polymerase chain reaction product of the flaA and flaB genes (fla typing) and pulsed-field gel electrophoresis (PFGE). A diversity in fla types and PFGE types was observed within and between flocks. Individual birds could be colonized by different genotypes at various intestinal and oviduct sites. However, the oviduct of individual birds appeared to be colonized by only one genotype at the time of sampling. In two birds, matching isolates investigated from the intestinal and reproductive tracts were genotypically identical but different from those oviduct isolates found in other birds in the same flock. Interestingly, not all cecal isolates appeared to be equally able to colonize the oviduct. These results suggest that oviduct colonization may result from ascending infection via the cloaca and that some strains of C. jejuni may be better adapted than others to oviduct colonization.  相似文献   

8.
Cloacal swabs from 487 live birds in 36 flocks and 70 poultry carcasses were cultured for Campylobacter fetus subsp. jejuni. It was isolated from 12.3% of the birds in 19 flocks. Chickens, turkeys, and guinea fowl differed from one another in isolation rates of the organism. Management system affected its occurrence, and only 7.1% of eviscerated carcasses yielded it. It was concluded that bird species, management system, and immersing slaughtered poultry in boiling water before dressing affect recovery of C. fetus subsp. jejuni from live birds and carcasses.  相似文献   

9.
Campylobacter jejuni, a foodborne pathogen closely associated with market poultry, is considered to be the most frequent agent of human gastroenteritis in the United States. The pathways involved in the contamination of poultry flocks, vertical transmission and/or horizontal transmission, are unclear. In this study, Campylobacter isolates from two independent commercial broiler breeder flocks, as well as from their respective progeny, were characterized and compared by PstI ribotype analysis and by DNA sequence analysis of the short variable region (SVR) of the flaA gene (flaA SVR). Campylobacter isolates originating from one set of breeder hens and the feces from their respective progeny demonstrated identical ribotype patterns as well as identical flaA SVR DNA sequences, thereby suggesting that these isolates were clonal in origin. Ribotype analysis of Campylobacter isolates from the second set of breeder hens and processed carcasses from their offspring resulted in two patterns. Sequence analysis placed these isolates into two closely related groups and one distant group, similar to the ribotype analysis. These results demonstrate that Campylobacter isolates from commercial broiler breeder flocks and from the respective broiler progeny may be of clonal origin and that breeder hens can serve as a source for Campylobacter contamination in poultry flocks.  相似文献   

10.
Pooled faeces samples from 106 poultry flocks in Norway were examined. Campylobacter fetus subsp. jejuni was isolated from 10 of 100 chicken flocks and from 4 of 6 turkey flocks. Eight of the 14 isolates were classified as biotype C. jejuni, which is frequently associated with human campylobacteriosis. Five strains belonged to the biotype C. coli. One strain was resistant to nalidixic acid but differed from the biotype NARTC in its ability to hydrolyse hippurate. The results indicate that C. fetus subsp. jejuni is widespread among Norwegian poultry.  相似文献   

11.
Thermotolerant Campylobacter spp., in particular Campylobacter jejuni, are among the most frequently identified pathogens, found to be causing human gastrointestinal infections in Europe, with the Czech Republic being no exception. The presented work aimed at assessing results of the first nationwide monitoring of prevalence and antibiotic resistance of Campylobacter spp. in broiler flocks in the Czech Republic, including a comparison of antibiotic resistance of C. jejuni isolates collected from poultry and the human community. The monitoring was carried out in poultry slaughterhouses in 2006 and 2007. From broilers, cloacal swabs were collected and examined. The human isolates of C. jejuni were acquired from rectal swabs in community patients with diarrhoeal diseases. Suspected isolates of both animal and human origin were confirmed by the PCR methods. Antibiotic resistance to selected anti-microbial agents was tested by the microdilution method. In the monitored period, the prevalence of thermotolerant Campylobacter spp. in broilers in the Czech Republic reached almost 50%. In 2006, C. jejuni was detected in 46% and Campylobacter coli in 3% of the tested samples. In 2007, C. jejuni was found in 43% and C. coli in 2% of the samples. The results of anti-microbial susceptibility testing of C. jejuni showed higher resistance in animals when compared with humans. The only exception was tetracycline with higher resistance in isolates of human origin. The highest resistance detected was to quinolone antibiotics. Resistance to oxolinic acid was 77% in animal and 60% in human isolates, to ciprofloxacin 72% in isolates from poultry and 55% in those from humans. In ampicillin, 26% of poultry isolates and 16% of human isolates were resistant. Moreover, 9% of animal isolates demonstrated resistance to streptomycin, undetected in human isolates. In erythromycin, resistance was found in 6% of poultry and 1% of human isolates.  相似文献   

12.
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   

13.
Twenty infectious bronchitis virus (IBV) field isolates obtained from commercial layer and broiler chickens in 1987 and 1988 were serotyped using the virus-neutralization (VN) test. Six different previously unrecognized variant serotypes were identified from a total of seven isolates from layer chickens. Only two isolates, both from Maine, were the same variant serotype. Variant serotypes also were recovered from layer flocks in Illinois and Washington and the province of Ontario, Canada. Two different variants were isolated from the same multi-age layer complex in Connecticut. Only one of 13 broiler chicken isolates was found to be a new variant serotype, that being from birds reared in Delaware. Cross-protection studies in specific-pathogen-free chickens indicated that vaccines containing the Holland, L-1, or Connaught strains of Massachusetts (Mass) combined with Arkansas produced a broader spectrum of immunity against challenge with the layer variants than Mass (Holland) alone or Mass (L-1) + Connecticut. All vaccines tested produced solid immunity (greater than or equal to 80% protection) against the broiler variant virus.  相似文献   

14.
Eight of 16 conventional broiler-chicken flocks examined contained Campylobacter. All isolates were identified as C. jejuni except from 1 flock were C. coli was isolated. One herd consisting of 6 different houses where Campylobacter regularly has been isolated was continuously examined. It was not possible to isolate Campylobacter from newly hatched chickens or from environmental samples and cloacal swabs during the 2 first weeks of growth.  相似文献   

15.
AIM: To type Campylobacter isolates from sheep abortions from the Hawke's Bay region of New Zealand. METHODS: Campylobacter isolates were collected from aborted sheep fetuses from commercial farms in the Hawke's Bay region. Information on the Campylobacter vaccination status of flocks in the study was collected. Isolates were identified to species level using standard phenotypic tests, then typed using pulsed-field gel electrophoresis (PFGE). RESULTS: Eighty-one C. fetus subsp. fetus isolates were cultured from aborted sheep fetuses from 25 farms and four C. jejuni isolates were cultured from fetuses from three farms. The C. fetus subsp. fetus isolates were classified into six PFGE groups. A single pulsed-field type predominated amongst isolates from 19 of the 25 farms. The C. jejuni isolates comprised two types. CONCLUSIONS: A range of C. fetus subsp. fetus PFGE types was identified, and one type, B1, was found most frequently. Campylobacter fetus subsp. fetus was only isolated from samples from sheep that had not been vaccinated with C. fetus subsp. fetus vaccine that season.  相似文献   

16.
The aim of this study was to assess the diversity of thermotolerant Campylobacter spp. isolated from turkey flocks at six rearing farms 1-2 weeks prior to slaughter (360 faecal swab samples) and from 11 different stages at the slaughterhouse (636 caecal, environmental, neck skin and meat samples). A total of 121 Campylobacter isolates were identified to species level using a multiplex PCR assay and were typed by pulsed-field gel electrophoresis (PFGE) and flaA-short variable region (SVR) sequencing. All Campylobacter isolates were identified as Campylobacter jejuni. PFGE analysis with KpnI restriction enzyme resulted in 11 PFGE types (I-XI) and flaA SVR typing yielded in nine flaA-SVR alleles. The Campylobacter-positive turkey flocks A, C and E were colonized by a limited number of Campylobacter clones at the farm and slaughter. The present study confirms the traceability of flock-specific strains (PFGE types I, V and IX; flaA types 21, 36 and 161) from the farm along the entire processing line to meat cuts. It seems that stress factors such as high temperature of the defeathering water (54-56 °C), drying of the carcass skin during air chilling (24 h at 2 °C), and oxygen in the air could not eliminate Campylobacter completely. Campylobacter-negative flocks became contaminated during processing by the same subtypes of Campylobacter introduced into the slaughter house by preceeding positive flocks even if they were slaughtered on subsequent days. Proper and efficient cleaning and disinfection of slaughter and processing premises are needed to avoid cross-contamination, especially in countries with a low prevalence of Campylobacter spp. The majority of flaA SVR alleles displayed a distinct association with a specific PFGE type. However, a linear relationship for all strains among both typing methods could not be established. To specify genetic relatedness of strains, a combination of different genotyping methods, is needed.  相似文献   

17.
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   

18.
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   

19.
A surveillance study for thermophilic Campylobacter spp. in broiler flocks was carried out for the year 1998 in Denmark. The study included examinations of 4286 broiler flocks comprising samples from 57,000 birds. Overall, a flock prevalence of 46.0% was recorded. The species distribution was Campylobacter jejuni 86%, Campylobacter coli 11%, Campylobacter lari 1%, other not further diagnosed species 2%. The prevalence was significantly higher in the period from June to October (3.2 < odds ratio [OR] <1.8, P < 0.0002) and was significantly associated with abattoir (OR < 2.8, P < 0.0001) and the length of the period the broiler houses were left empty between flocks (download period; 6 days or more) (OR = 1.6, P < 0.0198). No association between Campylobacter colonization and the age at slaughter was found. Separating the flocks into batches for slaughter elevated the flock prevalence from 0.41 after the first batch had been slaughtered to 0.46 after all batches had been slaughtered.  相似文献   

20.
Colonization of the ceca and organ invasion by different isolates of Campylobacter jejuni were investigated in day-of-hatch leghorn chicks. This model of Campylobacter colonization of the ceca demonstrates that 1) day-of-hatch birds do not naturally contain cecal Campylobacter, 2) ceca can be colonized with C. jejuni by oral gavage and not by cloacal inoculation; 3) C. jejuni can be recovered from the ceca up until at least 7 days postinoculation, 4) cecal colonization occurs when as little as 10(2) colony-forming units is orally inoculated into chicks, and 5) different C. jejuni isolates vary both in their ability to colonize the ceca and in their ability to invade the liver. These studies demonstrate that we have a working animal model for Campylobacter colonization for day-of-hatch chicks. This animal model is being used to examine intervention strategies such as vaccines by which Campylobacter can be reduced or removed from the food animal.  相似文献   

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