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1.
To compare the genotypes of Campylobacter jejuni and Campylobacter coli isolates of human and animal origin collected in Rio de Janeiro City, 30 C. jejuni and 35 C. coli isolates from animal sources (n = 45) and human patients with gastroenteritis (n = 20) were genotyped by PCR-based techniques, namely random amplified polymorphic DNA (RAPD-PCR) and enterobacterial repetitive intergenic consensus sequence (ERIC-PCR). RAPD-PCR identified 50 types and ERIC-PCR identified 22 genotypes, among the 65 Campylobacter isolates. Both PCR methods discriminated the C. jejuni and C. coli groups of isolates. Combining the results of both methods, no single genotype was shared between isolates from human and animal sources. Two groups of two C. coli isolates each with identical genotypes were found among poultry and pig isolates. A high level of genetic diversity observed among the Campylobacter isolates suggests lack of overlap between isolates from different sources.  相似文献   

2.
  1. Pediococcus spp. were isolated from poultry rectum, faeces and food as good probiotic candidates in order to select strains to be used as probiotic in poultry feed.

  2. A total of 168 lactic acid bacteria were isolated and 51 isolates including 31 Lactobacillus spp. and 20 Pediococcus spp. were able to survive in low pH and bile salt concentration. The Pediococcus spp. were identified and their ability to form biofilm, adhesion to Caco-2 cells and antimicrobial activities against enteric pathogenic bacteria were determined.

  3. The results showed the presence of two strains, Pediococcus acidilactici P17 and P19 in rectal swab samples from 21-d old chickens with significant antibacterial activities against Salmonella enteritidis and Escherichia coli.

  4. The results suggest that only a few isolates of Pediococcus with potential probiotic activities are present in the poultry industry.

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3.
Four gut Lactobacillus strains displaying the features which make them particularly promising for the preparation of probiotic products were investigated together with 5 fresh isolates and one collection strain of Lactobacillus plantarum for their ability to bind type I collagen (Cn-I). Immobilised Cn-I in microtitre plates was bound only by 3 strains of gut lactobacilli from piglets and the collection strain Lactobacillus plantarum LHI 10 from Prague in range of A570nm readings 0.114-0.221. Six strains (isolates from turkeys and a calf) did not bind Cn-I (A570nm < 0.1) in this assay. An influence of cultivation medium on Cn-I binding was significant (P < 0.001) in all four adherent strains. Significantly higher (P < 0.001) binding of Cn-I was observed for Lactobacillus casei L 81 and Lactobacillus plantarum LHI 10 grown on solid medium (MRS agar) than for MRS broth-grown cells, however, Lactobacillus plantarum L 5 and Lactobacillus fermentum L 435 expressed significantly (P < 0.001) higher Cn-I binding during cultivation in MRS broth. The specificity of the binding was confirmed because the Cn-I binding by lactobacilli after their preincubation with this protein was completely abolished. Three selected inhibitors (fucoidan, heparan sulphate and hyaluronic acid) significantly (P < 0.001) reduced Cn-I binding by the Lactobacillus plantarum L 5 strain. Following up on some earlier strain characteristics, these results suggest that the selected piglets lactobacilli are also able to bind Cn-I and therefore should antagonize collagen niche colonization by various enteropathogens when used for probiotic purposes.  相似文献   

4.
The present study was conducted to compare the S. aureus isolates from different sources in the basis of resistance phenotypic and genotypic features and phylogenetic differences. Total of 70 S. aureus isolates (including 25 human, 25 raw milk and 20 pet animal isolates) were subjected to the antimicrobial susceptibility testing, polymerase chain reaction (PCR) detection of the resistance genes and DNA fingerprinting using random amplification of polymorphic DNA–PCR (RAPD-PCR) to survey the variability of the isolates. Among 70 S. aureus, 55 (78.5%) isolates were MRSA. The isolates showed the highest antibiotic resistance to methicillin, ampicillin and penicillin (78.5%) and showed the lowest resistance to ciprofloxacin (12.8%). ErmB and tetM resistance genes were present in all isolates and the vanA gene was not detected in any of the isolates. Thirteen distinct clusters were identified in RAPD-PCR fingerprinting. Statistical analysis showed that the isolates without resistance to antibiotics were significantly in associated with raw milk origin (P < 0.05). According to the results of the study, S. aureus strains with pets and raw milk origin are significant sources of antibiotic-resistant isolates such as MRSA. They are also carriers of resistance genes that can be transmit to human isolates and cause drug resistance in human infections. Identifying the source of these infections is possible with a reliable genotyping method such as RAPD-PCR.  相似文献   

5.
  1. A total of 32 Lactobacillus isolates, 8 each from the crop (LGFCP1–LGFCP8), proventriculus (LGFP9–LGFP16), ileum (LGFI17–LGFI24) and caeca (LGFCM25–LGFCM32) were isolated from 25 adult guinea fowl (Pearl variety), 22–28 weeks of age, and characterised morphologically, physiologically, biochemically and by molecular methods.

  2. Isolates were screened for their probiotic quality using range of in vitro tests: aggregation test, cell surface hydrophobicity, resistance to bile salts and acidic conditions, enzymatic tests and coaggregation and antagonistic test.

  3. Based on in vitro test results and a novel scoring method, the two best isolates were selected and partial 16S rRNA sequencing was done. BLAST (Basic Local Alignment Search Tool) analysis of sequence of isolate LGFCP4 showed 99% genetic identity with Lactobacillus plantarum and LGFP16 with Lactobacillus reuteri.

  4. The study shows that these two microbial agents may be suitable as potential probiotic candidates in guinea fowl, as well as in a feed supplement for other poultry species.

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6.
The aim of this work was to investigate the effect of probiotic preparation with multi-strains composition (Lactobacillus delbrueckii ssp. bulgaricus LAT 187, Lactobacillus acidophilus LAT 180, Lactobacillus helveticus LAT 179, Lactobacillus delbrueckii ssp. lactis LAT 182, Streptococcus thermophilus LAT 205 and Enterococcus faecium E 253) on internal milieu, antioxidant status and body weight of broiler chickens. Chickens were divided into three groups (C, control; E1 and E2, experimental groups). Experimental chickens received the probiotic preparation in drinking water. Probiotic preparation caused a significant increase of serum calcium and potassium content. In the group with higher dose of probiotic strains serum triglycerides level decreased. Total antioxidant status in groups with addition of probiotic strains showed higher values in comparison to control group. Serum albumin level was found to increase after consumption of probiotic preparation in group with higher dose of probiotic strains. Probiotic strains improved body weight in last observed weeks of feeding.  相似文献   

7.
Twenty-three lactic acid bacteria (LAB) isolated from three cultivars (Akiaoba, Nagahahikari and Tachiwase) of Italian ryegrass (Lolium multiflorum Lam.) silage were precisely characterized by a combination of phenotypic tests, genotypic 16S ribosomal DNA sequencing and rapid PCR-based analyses, focusing on their useful phenotypes for silage preparation as inoculants. We successfully identified both at the species and subspecies levels: phenotypically novel Lactococcus lactis subsp. lactis, Lactobacillus brevis, Lactobacillus coryniformis subsp. torquens, Lactobacillus curvatus, Lactobacillus plantarum subsp. plantarum, Lactobacillus sakei subsp. carnosus, Leuconostoc mesenteroides subsp. dextranicum and Pediococcus parvulus. This is the first report to elucidate the presence of Lactobacillus coryniformis ssp. torquens and Leuconostoc mesenteroides subsp. dextranicum in Italian ryegrass silages. Physiological and biochemical tests revealed that phenotypic characteristics are different among the different strains of the same species and subspecies, and that the isolates show unique and diverse phenotypes related to fermentation factors, such as available carbohydrates, optimal growth pH and temperature. These results suggest that, for various well-preserved silage preparations, the isolates may be useful in producing novel inoculants corresponding to their optimally climatic and ecological niches.  相似文献   

8.
The aim of this study is to investigate the dynamic gut microbial diversity in weaning swine after administering feed supplemented with probiotic bacteria that specifically inhibit the activity of quorum molecules. Initially, the universal quorum molecule autoinducer‐2 (AI‐2) bioassay results indicated that AI‐2 activity was profoundly inhibited in enterohemorrhagic Escherichia coli (EHEC) O157:H7 in the presence of Lactobacillus acidophilus strain 30SC cell extract, although the growth of EHEC was not affected. Based on plate counting results, bacterial community analysis revealed a specific reduction in coliforms compared to the control, whereas the population of lactobacilli increased in weaning swine in in vivo trials. Supplementation with L. acidophilus strain 30SC did not affect the counts of other communities, such as total aerobes and yeast/mold. In addition, PCR‐denaturing gradient gel electrophoresis analysis showed a significant difference in the 16S rRNA gene products after administering L. acidophilus strain 30SC. Selected bands were sequenced, and most of them were identified as uncultured bacterium clones or a Lactobacillus‐ and Bifidobacterium‐specific community. Therefore, our results indicate that quorum‐quenching probiotic bacteria can significantly modulate the gut microbiota of swine and these beneficial effects can contribute to the improvement of performance and health in the gastrointestinal tract of weaning pigs.  相似文献   

9.
Adhesion tests are complex, time‐consuming and expensive, while the most important criterion for a probiotic lactobacilli is the ability to adhere to the human intestine. Thirty lactobacilli isolates from human intestinal tissues were measured for cell surface glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) activity using a microtiter plate screening method. GAPDH activities were detected in 21 out of 30 samples from 12 h cultures and in all samples from 18 h cultures. This suggests GAPDH is universally expressed on the bacterial cell surfaces from many lactobacilli. A statistically significant positive correlation was shown between GAPDH activity and adhesion using the BIACORE adhesion assay (P < 0.01). The new screening method using GAPDH enzymatic activity without an adhesion test may be possible due to the significant positive correlation of GAPDH activity with adhesion of lactobacilli derived from the human intestine.  相似文献   

10.
The health of poultry is closely related to how the animals are raised, and the gut microbiota plays a key role in the fulfillment of their productive potential. Lactobacillus spp. are bacteria present in the natural microbiota of poultry that, when employed as probiotic agents, should present several characteristics. This study aims at performing the in vitro probiotic isolation and characterization of Lactobacillus spp. Isolates were obtained from ceca content of healthy turkeys through the isolation and identification of morphological, molecular, and physiologic characteristics. They were identified through Gram staining, catalase and hydrogen peroxide production tests, gas production tests during glucose fermentation, and hydrogen sulfide production during the triple sugar iron test. The samples were identified molecularly through polymerase chain reaction tests and were subjected to genetic sequencing. The assessment of the probiotic potential was conducted through artificial gastric juice tolerance and bile salt tolerance tests. A hydrophobicity test was used as an indirect method of assessing an isolate’s probable ability to adhere to the intestinal mucosa. In addition, other analyses were performed, such as multiplication potential tests, Salmonella Heildelberg antagonism assays, hydrogen peroxide production tests, and antibiograms, as well as an assessment of the genes responsible for resistance to antimicrobial agents in Integron C. In conclusion, we identified, through morphologic, physiologic, pathogen antagonism, and antimicrobial resistance tests, 11 strains of Lactobacillus spp. belonging to species L. reuteri (9), L. johnsonii (1), and L. frumenti (1) that showed potential as probiotic candidates for in vivo application.  相似文献   

11.
Three gut lactobacilli from piglets (Lactobacillus plantarum L 5, Lactobacillus paracasei L 81, Lactobacillus fermentum L 670) and Lactobacillus casei subsp. pseudoplantarum L.c.) from a calf were examined by microtitre plate binding assay for their lectin-like binding activity after their cultivation on Rogosa agar and in MRS broth. Three ECM (extracellular matrix) molecules (fetuin, porcine fibronectin and porcine mucin) were selected for this assay. Additionally, the effect of heparin on the binding of these three ECM molecules by Lactobacillus strains in microtitre plates was tested. Moreover, haemagglutination tests with pig, cattle, sheep, and hen erythrocytes were performed. However, none of the four Lactobacillus strains examined did react with any of the erythrocytes tested. The differences between individual strains were observed in their binding to immobilised ECM molecules. The best adherent was the Lactobacillus plantarum L5, however, the other three strains showed also good ECM binding. With regard to an influence of cultivation medium on lectin-like binding activity, binding of all ECM molecules was expressed in Lactobacillus paracasei L 81 to significantly higher degree (P < 0.001) after cultivation on Rogosa agar than in MRS broth. Similarly, strains Lactobacillus fermentum L 670 and Lactobacillus casei subsp. pseudoplantarum L.c. displayed significantly higher (P < 0.001) binding of fibronectin and mucin after growth on Rogosa agar in comparison with MRS broth cultivation. However, no significant (on fetuin and fibronectin binding) or opposite effect (on mucin binding) of cultivation medium was observed in Lactobacillus plantarum L 5 strain. The influence of cultivation medium on fetuin binding by Lactobacillus fermentum L 670 was also not significant while Lactobacillus casei subsp. pseudoplantarum L.c. bound fetuin significantly better (P < 0.01) after growth on Rogosa agar. Heparin pretreatment increased the binding of the ECM molecules by the Lactobacillus fermentum L 670 strain significantly (P < 0.001 or P < 0.05) with the exception of porcine fibronectin when the strain was cultivated in MRS broth. This result is important especially in the connection with the previous observations that heparin decreased ECM binding of enteropathogens as staphylococci or clinical enterococcal isolates. Following up on some earlier strain characteristics, these results indicate that the selected lactobacilli are probably suitable for probiotic purposes.  相似文献   

12.
Erysipelothrix rhusiopathiae infections re-emerged as a matter of great concern particularly in the poultry industry. In contrast to porcine isolates, molecular epidemiological traits of avian E. rhusiopathiae isolates are less well known. Thus, we aimed to (i) develop a multilocus sequence typing (MLST) scheme for E. rhusiopathiae, (ii) study the congruence of strain grouping based on pulsed-field gel electrophoresis (PFGE) and MLST, (iii) determine the diversity of the dominant immunogenic protein SpaA, and (iv) examine the distribution of genes putatively linked with virulence among field isolates from poultry (120), swine (24) and other hosts (21), including humans (3). Using seven housekeeping genes for MLST analysis we determined 72 sequence types (STs) among 165 isolates. This indicated an overall high diversity, though 34.5% of all isolates belonged to a single predominant ST-complex, STC9, which grouped strains from birds and mammals, including humans, together. PFGE revealed 58 different clusters and congruence with the sequence-based MLST-method was not common. Based on polymorphisms in the N-terminal hyper-variable region of SpaA the isolates were classified into five groups, which followed the phylogenetic background of the strains. More than 90% of the isolates harboured all 16 putative virulence genes tested and only intI, encoding an internalin-like protein, showed infrequent distribution. MLST data determined E. rhusiopathiae as weakly clonal species with limited host specificity. A common evolutionary origin of isolates as well as shared SpaA variants and virulence genotypes obtained from avian and mammalian hosts indicates common reservoirs, pathogenic pathways and immunogenic properties of the pathogen.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0216-x) contains supplementary material, which is available to authorized users.  相似文献   

13.
Lactobacillus sp. are important inhabitants of the intestines of animals. They are also largely used as probiotics for both humans and animals. To exert beneficial effects, lactobacilli have to survive through the gastrointestinal transit. Based on bile-salt resistance, pH tolerance, antimicrobial activity and heat resistance, Lactobacillus plantarum 4.1 and Lactobacillus reuteri 3S7 were previously selected and used as probiotic additives in pelleted feeding trials. Both strains were fed to pigs (sows and piglets) at a cell number of ca. 10(10) viable cells per day. A polyphasic approach, comprising growth on selective media, Biolog System analysis, 16S rRNA gene sequencing and RAPD-PCR typing, was used to identify and differentiate L. plantarum 4.1 and L. reuteri 3S7 from other faecal Lactobacillus sp., L. plantarum 4.1 and L. reuteri 3S7 had the capacity to survive during the gastrointestinal transit and were found in the feaces at a cell number of 6-8 log cfu/g. Their persistence was shown after 6 days from the administration. Compared to untreated pigs, the administration of L. plantarum 4.1 and L. reuteri 3S7 significantly (P<0.05) decreased the population of Enterobacteriaceae. Besides, the beta-glucuronidase activity of all pigs decreased of ca. 23.0% during administration. The findings of this study showed that L. plantarum 4.1 and L. reuteri 3S7 have the potential to be used as probiotic additives in pelleted feed for pigs.  相似文献   

14.
Introduction and purposeDespite the various vaccination programs for protection against New Castle disease, it remains an important threat to the poultry industry. The ability of the probiotic bacteria to improve the immune system in both animals and humans supports their use as immune adjuvants for vaccination. The aim of the present study was to examine the effects of Lactobacillus acidophilus in ND vaccination.Materials and methodsA total of 170 one day old chicks were divided in 5 groups. In groups A, B and C chicks were received L. acidophilus (5 × 109, 3 × 109 and 2 × 109) and also vaccinated with inactivated and attenuated ND vaccines. In group D, chicks only vaccinated without bacterial inoculation and group E was negative control with neither vaccine nor bacteria. Then IgG and HI NDV antibody titers were measured in all tested groups.ResultsIgG and HI NDV antibody levels were significantly higher in Lactobacillus treated groups especially in group A with 5 × 109 bacteria, than only vaccinated and negative control groups. Also antibody levels against NDV increased during the vaccination period especially in probiotic treated groups.ConclusionIn conclusion, L. acidophilus can use for improving immunogenicity of NDV vaccination programs.  相似文献   

15.
Salmonella Livingstone is occasionaly isolated from humans, animals and feedstuffs in Sweden. To follow the spread of infection and trace the source of isolates, adequate typing methods are needed. We have developed an automated typing system based on biochemical fingerprinting of bacteria (the PhP system) for typing of different Salmonella serotypes. The system measures the kinetics of various biochemical reactions of bacteria grown in liquid medium in microtiter plates and uses numerical techniques to identify biochemical phenotypes (BPTs) among the tested strains. In the present study we used a set of 16 highly discriminatory tests to differentiate strains of Salmonella of serotype Livingstone and evaluated the system for its discriminatory ability using a collection of 34 unrelated human isolates of S. Livingstone. We also used the system to investigate BPTs of 45 Livingstone strains isolated from animals and feedstuffs in Sweden between 1987 and 1991. Altogether 19 different BPTs were found among human isolate giving a diversity index (Di) of 0.930. In contrast, most strains isolated from animals and feedstuffs in Sweden belonged to 2 dominating BPTs (Di = 0.704). One of these contained 17 strains mainly isolated during 1992 whereas the other contained 18 strains isolated between 1987 and 1991. None of the Swedish human isolates were identical to those of animals and feedstuffs. These findings suggest that 2 different BPTs of Salmonella Livingstone strains are particularly common among animals and feedstuffs in Sweden and that they are not related to human cases of enteritis in this country. We also conclude that biochemical fingerprinting with the PhP system is a reliable and highly discriminatory method for detecting epidemic strains of Salmonella Livingstone.  相似文献   

16.
Campylobacter is the most common cause of bacterial food‐borne diarrhoeal disease throughout the world. The principal risk of human contamination is handling and consumption of contaminated poultry meat. To colonize poultry, Campylobacter adheres to and persists in the mucus layer that covers the intestinal epithelium. Inhibiting adhesion to the mucus could prevent colonization of the intestine. The aim of this study was to investigate in vitro the protective effect of defined commercial human probiotic strains on the adhesion of Campylobacter spp. to chicken intestinal mucus, in a search for alternatives to antibiotics to control this food‐borne pathogen. The probiotic strains Lactobacillus rhamnosus GG and Propionibacterium freudenreichii ssp. shermanii JS and a starter culture strain Lactococcus lactis ssp. lactis adhered well to chicken intestinal mucus and were able to reduce the binding of Campylobacter spp. when the mucus was colonized with the probiotic strain before contacting the pathogen. Human‐intended probiotics could be useful as prophylactics in poultry feeding for controlling Campylobacter spp. colonization.  相似文献   

17.
Lactic acid bacteria are considered indigenous members of the gastrointestinal microflora in a number of animal species (Savage 1977a). Some intestinal strains of lactobacilli and streptococci are aWe to adhere to stratified squamous epithelium of some animals (Tannock et al. 1987), in the non-secreting part of the stomach of piglets (Barrow et al. 1980, Fuller et al. 1978) and rodents (Tannock et al. 1982), and in the crop of poultry (Fuller 1978). The presence of lactic acid bacteria in the digestive tract is believed to be of beneficial value to the host animal (Fuller 1989). The production of organic acids in the stomach or the crop helps maintaining a low pH which may be important for inhibiting the colonization of potentially pathogenic bacteria, particularly in the newborn animal (Barrow et al 1980, Fuller 1977, Fuller 1978). The adhesion of lactobacilli to squamous epithelium is host specific: strains capable of adhering to the epithelium of piglets are usually not able to adhere in rodents or poultry and vice versa (Fuller 1978, Lin & Savage 1984, Tannock et al 1982). Adhesion of lactic acid bacterial strains to other epithelia than stratified squamous epithelium has been reported. Thus, the attachment of lactobacilli to cells from the secreting epithelium of the murine stomach (Kotarski & Savage 1979), to intestinal cells of humans (Goldin & Gorbach 1987), and to columnar epithelial cells of piglets and calves (Mäyrä-Mäkinen et al 1983) has been demonstrated using in vitro methods. In another study the in vivo attachment of Enterococcus faecium to duodenal epithelium of gnotobi-otic chickens was demonstrated (Fuller et al 1981). Recent research indicated that in adult mink lactic acid bacteria are not indigenous members of the intestinal flora, and they do not attach to epithelium in any part of the gastrointestinal tract (Federsen & Jørgensen 1992). The present paper presents evidence that Gram positive cocci may colonize the gut of suckling mink kits and attach to the gut mucosa.  相似文献   

18.
Chronic infection with Helicobacter pylori (H. pylori) is a known risk factor for gastric cancer. Eradication rate of H. pylori infection by the classic triple treatment of PPIs and antibiotics is low. Therefore, probiotics are a useful tool for improving the rate of eradication and reduction of side effects. Several studies in animal models showed that Lactobacillus spp. alone and in combination with other probiotic strains have inhibitory effects on growth and suppression of inflammatory responses in H. pylori infections. However, some studies showed significant effects of Pediococcus strains on suppression, survival, and eradication of H. pylori infections. Therefore, it is suggested that in the treatment of H. pylori infections along with the usual probiotic strains, different strains of Pediococcus could be used. Recent studies showed that Lactobacillus reuteri and Lactobacillus gasseri alone with PPIs in human have a high eradication effect on H. pylori infections and it is suggested as the probiotic treatment of patient's in future therapeutic protocols. In relation to the probiotic treatment process, it should not be recommended that probiotics could be used as a single treatment for H. pylori eradication. However, use of probiotics as a supplement will increase eradication and reduce side effects associated with treatment. It is widely believed that probiotics could improve the eradication of H. pylori and reduce side effects during standard treatment, but some probiotic bacterial species could be useful with drug therapy. Generally, probiotic supplements could increase the eradication rate of H. pylori infections and reduced the side effects of antibiotics.  相似文献   

19.
Salmonella enterica Enteritidis is the most frequent etiological agent of salmonellosis in humans and poultry. To understand the genetic diversity of S. Enteritidis in Iran, we examined 69 chicken isolates from 18 broiler farms and six non-epidemic human isolates from six geographically distant provinces by multi-locus variable-number tandem repeat analysis (MLVA). Among SE2, SE3, SE5, SE7, SE8, SENTR4, and SENTR7, only SE5 with four and SENTR7 with two alleles, respectively, proved variable giving estimates of locus genetic diversity of 0.58 and 0. In all, six closely related MLVA profiles were identified among which three were commonly represented by human and chicken isolates. This population homogeneity contrasts with the high diversity at these loci reported elsewhere and is likely a consequence of a single clone of S. Enteritidis distributed across Iran.  相似文献   

20.
Nineteen flocks of four poultry species were monitored at a veterinary field station to investigate the distribution and spread of Campylobacter genotypes between sequential and adjacent flocks. Caecal and liver samples were obtained at frequent intervals from birds of all flocks and examined for Campylobacter. Amplified fragment length polymorphism (AFLP) analysis was performed to genotype Campylobacter isolates. Of the 1643 caecal and liver samples investigated, 452 (27.5%) caecal samples and 11 (0.7%) liver samples contained Campylobacter. Of the caecal isolates 76.3% were identified as Campylobacter jejuni and 23.7% were identified as Campylobacter coli. Poultry flocks were largely colonized by more than one AFLP type and an intense exchange of Campylobacter genotypes between different poultry flocks occurred. These findings indicate that multiple genotypes can constitute the Campylobacter population within single poultry flocks, hinting to different sources of exposure and/or genetic drifts within the Campylobacter population. Nevertheless, in most flocks single Campylobacter genotypes predominated. Some strains superseded others resulting in colonization by successive Campylobacter genotypes during the observation period. In conclusion, the data demonstrate that the large genetic diversity of Campylobacter must be considered in epidemiological evaluations and microbial risk assessments of Campylobacter in poultry.  相似文献   

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