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1.
The absence of cecal colonization of chicks by a mutant of Campylobacter jejuni not expressing bacterial fibronectin-binding protein. 总被引：5，自引：0，他引：5
Campylobacter jejuni is a common cause of human gastrointestinal illness throughout the world. Infections with C. jejuni and Campylobacter coli are frequently acquired by eating undercooked chicken. The ability of C. jejuni to become established in the gastrointestinal tract of chickens is believed to involve binding of the bacterium to the gastrointestinal surface. A 37-kD outer membrane protein, termed CadF, has been described that facilitates the binding of Campylobacter to fibronectin. This study was conducted to determine whether the CadF protein is required for C. jejuni to colonize the cecum of newly hatched chicks. Day-of-hatch chicks were orally challenged with C. jejuni F38011, a human clinical isolate, or challenged with a mutant in which the cadF gene was disrupted via homologous recombination with a suicide vector. This method of mutagenesis targets a predetermined DNA sequence and does not produce random mutations in unrelated genes. The parental C. jejuni F38011 readily colonized the cecum of newly hatched chicks. In contrast, the cadF mutant was not recovered from any of 60 chicks challenged, indicating that disruption of the cadF gene renders C. jejuni incapable of colonizing the cecum. CadF protein appears to be required for the colonization of newly hatched leghorn chickens. 相似文献
2.
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
3.
Day-old, straight-run broiler chickens were procured from a hatchery located in the Pacific Northwest. The chickens were subdivided individually into nine groups of 20 chickens. The chickens were tagged, housed in isolation chambers on wire, fed commercial broiler feed, and given water ad libitum. Three isolates of Campylobacter jejuni of poultry origin and one of human origin were tested in this study. Various C. jejuni cultures were inoculated into 9-day-old chickens by crop gavage. Four groups of 20 chickens were inoculated at a dose level of 0.5 ml of 1 x 10(2) colony-forming units (CFU)/ml. The other four groups were inoculated with 0.5 ml of 1 X 10(4) CFU/ml. One group of 20 chickens was kept as an uninoculated control group. Four randomly selected chickens from each of the inoculated and uninoculated groups were necropsied at 5, 12, and 19 days postinoculation (DPI). The C. jejuni was cultured and enumerated from a composite of the upper and midintestine and the cecum. Body weights of all chicken groups at 7 days of age and at 5, 12, and 19 DPI were measured and statistically analyzed. No significant differences were present in the mean body weights (MBWs) of 7-day-old, 5 DPI, and 12 DPI male and female broiler chickens inoculated with C. jejuni at both dose levels compared with uninoculated controls. Differences in MBWs of the male and female broilers at 19 DPI were observed in some of the groups. Results of the C. jejuni culture enumeration mean (CEM) of composite intestine samples at 5 DPI from all inoculated chicken groups, irrespective of the dose level, ranged from (2.5 +/- 5.0) x 10(2) to (2.8 +/- 4.8) x 10(5) CFU/g (mean +/- SD). Results of cecum C. jejuni CEM at 5 DPI inoculated at both dose levels ranged from (2.5 +/- 5.0) x 10(6) to (1 +/- 0.0) x 10(7) CFU/g in all treatment groups irrespective of the dose level. CEM results from the composite intestine samples at 12 and 19 DPI increased by 1 log unit, or sometimes more. Results of cecum C. jejuni CEM at 5 DPI inoculated at both dose levels ranged from (2.5 +/- 5.0) x 10(6) to (1 +/- 0.0) x 10(7) CFU/g in all treatment groups irrespective of the dose level. Increases of 2-5 log units in C. jejuni CEM was present in chicken groups inoculated with 1 X 10(2) CFU of C. jejuni, and a 2- to 3-log increase was present in groups inoculated with a higher dose level of C. jejuni at 12 DPI. The results of C. jejuni CEM from cecal samples at 19 DPI were similar to chicken groups at 12 DPI. Campylobacterjejuni was not isolated from the uninoculated control chickens at 5, 12, and 19 DPI. Clinical signs of illness or gross pathologic lesions were not present in any of the chicken groups during this study. No lesions were present on histopathologic evaluations in C. jejuni-inoculated chickens or uninoculated control chickens. 相似文献
4.
Ziprin RL Young CR Byrd JA Stanker LH Hume ME Gray SA Kim BJ Konkel ME 《Avian diseases》2001,45(3):549-557
Campylobacter jejuni, a common commensal in chickens, is one of the leading causes of bacterial gastroenteritis in humans worldwide. The aims of this investigation were twofold. First, we sought to determine whether mutations in the C. jejuni ciaB and pldA virulence-associated genes impaired the organism's ability to colonize chickens. Second, we sought to determine if inoculation of chicks with C. jejuni mutants could confer protection from subsequent challenge with the C. jejuni wild-type strain. The C. jejuni ciaB gene encodes a secreted protein necessary for the maximal invasion of C. jejuni into cultured epithelial cells, and the pldA gene encodes a protein with phospholipase activity. Also included in this study were two additional C. jejuni mutants, one harboring a mutation in cadF and the other in dnaJ, with which we have previously performed colonization studies. In contrast to results with the parental C. jejuni strain, viable organisms were not recovered from any of the chicks inoculated with the C. jejuni mutants. To determine if chicks inoculated with the C. jejuni mutants become resistant to colonization by the C. jejuni parental strain upon subsequent challenge, chicks were inoculated either intraperitoneally (i.p.) or both orally and i.p. with the C. jejuni mutants. Inoculated birds were then orally challenged with the parental strain. Inoculation with the C. jejuni mutants did not provide protection from subsequent challenge with the wild-type strain. In addition, neither the C. jejuni parental nor the mutant strains caused any apparent morbidity or mortality of the chicks. We conclude that mutations in genes cadF, dnaJ, pldA, and ciaB impair the ability of C. jejuni to colonize the cecum, that chicks tolerate massive inoculation with these mutant strains, and that such inoculations do not provide biologically significant protection against colonization by the parental strain. 相似文献
5.
Wagenaar JA Van Bergen MA Mueller MA Wassenaar TM Carlton RM 《Veterinary microbiology》2005,109(3-4):275-283
The effect of phage therapy in the control of Campylobacter jejuni colonization in young broilers, either as a preventive or a therapeutic measure, was tested. A prevention group was infected with C. jejuni at day 4 of a 10-day phage treatment. A therapeutic group was phage treated for 6 days, starting 5 days after C. jejuni colonization of the broilers had been established. Treatment was monitored by enumerating Campylobacter colony forming units (CFU) and phage plaque forming units (PFU) from caecal content. Counts were compared with control birds not receiving phage therapy. A clear 3 log decline in C. jejuni counts was initially observed in the therapeutic group, however, after 5 days bacterial counts stabilized at a level 1 log lower than that of the control group. Colonization of C. jejuni in the prevention group was delayed by the treatment and after an initial 2 log reduction, colonization stabilized within a week at levels comparable to the therapeutic group. The CFU and PFU counts displayed opposing highs and lows over time, indicative of alternating shifts in amplification of bacteria and phages. There were no adverse health effects from the phage treatment. Two different phages were combined as therapeutic treatment of Campylobacter positive chickens challenged at the age approaching broiler harvest. This again resulted in a significant decrease in Campylobacter colonization. We conclude that phage treatment is a promising alternative for reducing C. jejuni colonization in broilers. 相似文献
6.
Three groups of neonatal calves were inoculated orally with pathogenic strains of Campylobacter jejuni or C coli. The calves developed a mild, self-limiting enteritis characterized by thick mucoid feces. Bacteremia and fecal shedding of Campylobacter were sporadic in all inoculated calves. Two groups of calves were killed 1 to 3 weeks after inoculation to study the pathogenesis of infection. Postmortem culture of tissues revealed C jejuni or C coli most frequently in the ileum, cecum, colon, and blood. Clinical or pathologic differences between C jejuni-inoculated and C coli-inoculated calves were minimal. 相似文献
7.
Molatová Z Skřivanová E Baré J Houf K Bruggeman G Marounek M 《Journal of animal physiology and animal nutrition》2011,95(6):701-706
The aim of this study was to examine whether and to what extent the supplementation of feed with a coated or non-coated mixture of fatty acids (caprylic and capric acid) affects broiler chickens experimentally infected with Campylobacter jejuni. The study was carried out using 48 chickens divided into four experimental groups. Throughout the whole rearing period (1-42 days), the chickens were fed a diet supplemented with 0.25% caprylic and capric acid (1:1), coated or non-coated. At the age of 14 and 28 days, chickens were orally challenged with C. jejuni. At regular time intervals post-inoculation, the shedding of C. jejuni was assayed using quantitative real-time PCR. Both supplements significantly decreased faecal C. jejuni counts by 1.2-4.1 log(10) CFU/g 4 days post-inoculation; after this time period, the effect of medium-chain fatty acids (MCFA) was less pronounced or absent. Campylobacter jejuni counts in excreta samples were significantly lower in chickens fed coated MCFA than in those fed non-coated MCFA. No effect of MCFA on feed intake or growth of chickens was observed. In conclusion, (i) MCFA are active against C. jejuni and (ii) the encapsulation enhanced the efficacy of the acids. These results allow the recommendation of using MCFA as feed additives in chickens, preferably 2-3 days before slaughter. 相似文献
8.
9.
The aim of the study was to evaluate the colonizing ability and the invasive capacity of selected Campylobacter jejuni strains of importance for the epidemiology of C jejuni in Danish broiler chickens. Four C. jejuni strains were selected for experimental colonization studies in day-old and 14-day-old chickens hatched from specific pathogen free (SPF) eggs. Of the four C. jejuni strains tested, three were Penner heat-stable serotype 2, flaA type 1/1, the most common type found among broilers and human cases in Denmark. The fourth strain was Penner heat-stable serotype 19, which has been shown to be associated with the Guillain Barré Syndrome (GBS) in humans. The minimum dose for establishing colonization in the day-old chickens was approximately 2 cfu, whereas two- to threefold higher doses were required for establishing colonization in the 14-day-old chickens. Two of the C. jejuni strains were shown to be invasive in orally challenged chickens as well as in three different human epithelial cell lines. 相似文献
10.
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
11.
Role of litter in the transmission of Campylobacter jejuni 总被引：3，自引：0，他引：3
Autoclaved or non-autoclaved used broiler litter that was experimentally contaminated with Campylobacter jejuni was capable of infecting specific-pathogen-free chicks maintained in modified Horsfall isolators. Artificially infected chicks became fecal shedders of C. jejuni, resulting in contamination of both autoclaved and non-autoclaved used broiler litter. Fecal shedding of C. jejuni by litter-reared, artificially infected chicks persisted for at least 63 days after chicks were transferred to an isolation unit with a wire floor, which prevented coprophagy. C. jejuni was consistently recovered from water and litter in units housing directly and indirectly infected birds, indicating environmental contamination. These experiments demonstrate the potential role of litter in the perpetuation and transmission of C. jejuni infection in commercial chickens. 相似文献
12.
Effects of diet formulations containing proteins from different sources on intestinal colonization by Campylobacter jejuni in broiler chickens 
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下载免费PDF全文 Roy S. Udayamputhoor Harry Hariharan Ted A. Van Lunen P. Jeffrey Lewis Susan Heaney Lawrence Price David Woodward 《Canadian journal of veterinary research》2003,67(3):204-212
The objective of this study was to compare the effects of 3 diet formulations containing different protein sources (animal, plant, and a combination of animal and plant) on the colonization of Campylobacter jejuni in the gastrointestinal tract of broiler chickens. A freshly isolated strain of C. jejuni (biotype IV, serotype HS O:21, O:29, HL untypable) from a broiler chicken was used to infect 3-day-old chicks that had been free of C. jejuni; 0.5 mL of an inoculum containing 108 colony-forming units was administered orally. Shedding of the organism was studied, and C. jejuni in the ceca, jejuni, and crop were enumerated by quantitative culture. The isolates recovered from the birds during the study period of 35 d were characterized and confirmed as C. jejuni by the use of standard methods and underwent biotyping, serotyping, antimicrobial susceptibility testing by disk diffusion and the E-test, and flagellin gene typing. A cyclical pattern of shedding of C. jejuni was observed in all the birds. Colonization was highest in the ceca. The ceca of birds receiving plant-protein-based feed had significantly less colonization then the ceca of birds receiving the other types of feed, whereas the differences in colonization of the jejuni and crops were not significant. Characterization by biotyping, serotyping, and flagellin gene typing showed that 95% of the recovered isolates were identical to the strain used for infecting the chicks. However, with the Lior-HL typing scheme, 74% of the recovered isolates were HL untypable. Antimicrobial resistance testing did not reveal significant differences between the infecting strain and the recovered isolates among the different feed groups. 相似文献
13.
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
14.
We report our findings on several parameters influencing cecal colonization of chickens by Campylobacter jejuni. Thirty-five colony-forming units (CFU) of a composite culture of C. jejuni colonized the ceca of one-half of the newly hatched chicks challenged by oral gavage. A challenge dose of 3500 CFU/chick consistently colonized the ceca of all chicks challenged. Challenge doses of approximately 10(5) CFU of C. jejuni per chick resulted in consistent cecal colonization, regardless of whether the birds were challenged 1, 2, or 3 days post-hatch. Four isolates showed consistently strong cecal colonization abilities, whereas two isolates colonized the ceca in only 20 of 122 chicks when given levels of 10(5) CFU per chick. One of these poorly colonizing isolates was repeatedly transferred by fecal-oral passage through chicks; subsequently, this isolate was able to consistently colonize chicks. Competitive exclusion (CE) microflora did not diminish the colonization rates for C. jejuni. Birds treated with five different CE cultures were colonized at a rate of 81 of 84 chicks; control chicks were similarly consistently colonized (45 of 46 chicks). 相似文献
15.
The study deals with the results of the investigation of C. jejuni populations in the intestines of gnotobiotic piglets after oral infection with C. jejuni in the span of one to five days after infection (DAI). The infection of the whole large intestine was revealed, with the onset of pathological lesions 3rd DAI. C. jejuni was isolated from liver, gallbladder, ileum, rectum, colon, mesenterial lymphatic node, rectal smears and blood. From 1st to 5th DAI C. jejuni was demonstrated in liver, gallbladder and posterior part of ileum. In the cecum and rectum C. jejuni was detected as late as on 2nd-3rd DAI to 5th DAI and in mesenterial lymphatic nodes from 2nd to 4th DAI. In rectal smears C. jejuni was found out regularly during the whole period of experiment. C. jejuni was also isolated from inflammatory infiltrate. Histological examination revealed C. jejuni between the villi and in the contents of cup-shaped cells from 2nd to 5th DAI. 相似文献
16.
G Glünder S Petermann 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(2):123-130
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
17.
Influence of Campylobacter jejuni cecal colonization on immunoglobulin response in chickens 总被引：1，自引：0，他引：1
The immunoglobulin response of chickens to colonization by Campylobacter jejuni isolates B-540 and Clin-1 was monitored. Chicken humoral IgG and biliary secretory IgA (sIgA) responses were assessed by enzyme-linked immunosorbent assay (ELISA). Samples were taken from 128 C. jejuni-colonized chickens and 104 uncolonized chickens housed in a controlled environment. An indirect ELISA was performed using the homologous isolate of C. jejuni as the capture antigen and was developed with the specific goat anti-chicken IgG or IgA alkaline phosphatase conjugates. The ELISA absorbance values of the test samples at 405 nm (serum diluted 1:32 and bile diluted 1:10) were normalized in direct proportion to standard sera and bile sample values. In the colonized chickens, humoral IgG activities were highest at hatch, dropped to their lowest level after 2 weeks, and increased by 8 weeks to levels similar to those detected at hatch. The sIgA activity was lowest at hatch and increased by 4 weeks in colonized chickens while remaining lower in the control chickens. Chickens colonized with isolate B-540 showed a primary sIgA response during the first 4 weeks and reached a plateau over the final 4 weeks. In spite of these limited humoral and secretory immunoglobulin responses, once the chicken ceca was colonized by C. jejuni, the organism persisted throughout the 8-week experiment. 相似文献
18.
Cox NA Hofacre CL Bailey JS Buhr RJ Wilson JL Hiett KL Richardson LJ Musgrove MT Cosby DE Tankson JD Vizzier YL Cray PF Vaughn LE Holt PS Bourassaa DV 《Avian diseases》2005,49(1):155-158
Day-old broiler chicks (n=30) were obtained from a commercial hatchery and inoculated, either orally or intracloacally, with a characterized strain of Campylobacter jejuni. At 1 hr, 1 day, and 1 wk after inoculation, broilers (n = 5) from the orally and intracloacally inoculated groups along with control birds (n=4) were humanely killed by cervical dislocation. The broilers from the control and treatment groups were aseptically opened, and the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca were aseptically removed and individually analyzed for C. jejuni. Overall, C. jejuni was isolated after oral inoculation from 13% (10/ 75), 17% (13/75), and 28% (14/50) of the 1-hr, 1-day, and 1-wk samples, respectively. Campylobacter jejuni was isolated from 10% (4/ 40), 8% (3/40), 10% (4/40), 25% (10/40), and 40% (16/40) of the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca samples, respectively. Following the intracloacal route of inoculation, C. jejuni was recovered from 32% (24/75), 8% (6/75), and 16% (8/50) of the 1-hr, 1-day, and 1-wk samples, respectively. Campylobacter jejuni was isolated from 5% (2/40), 5% (2/40), 5% (2/40), 45% (18/40), and 40% (16/40) of the thymus, spleen, liver/gallbladder, bursa of Fabricius, and ceca samples, respectively, for all sampling periods. Campylobacter spp. were not recovered from sample sites examined from the control broilers from trial one, trial two, or trial three samples examined after 1 hr and 1 day. However, one control sample was positive from the 1-wk sampling from repetition three; therefore, those data were omitted. The rapid movement of Campylobacter to internal organs following both oral and intracloacal inoculation may be significant, particularly if it persists in these organs as reservoirs throughout the 65-wk life cycle of breeding birds. 相似文献
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20.
Leblanc Maridor M Denis M Lalande F Beaurepaire B Cariolet R Fravalo P Federighi M Seegers H Belloc C 《Veterinary microbiology》2008,131(3-4):309-317
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