Campylobacter Colonization Research Articles

Antagonistic activities of several bacteria on in vitro growth of 10 strains of Campylobacter jejuni/ coli

Chicken meat contaminated with Campylobacter jejuni can be the source of human enteritis. To decrease the risk of human infection, Campylobacter should be controlled at farm levels. Orally given probiotic bacteria could prevent colonisation of chicken with pathogenic bacteria like Campylobacter. The aim of this study was to investigate the effect of different bacteria on Campylobacter growth. Our results demonstrated that bacteria isolated from conventional chicken had potential inhibitory activities against Campylobacter. Other bacteria not isolated from chickens but with known antagonistic capacities, e.g. Enterococcus (56 strains) and Escherichia coli (20 strains), did not show any negative effect on Campylobacter. Interestingly, one Lactobacillus (P93) strain isolated from the chicken gut showed bactericidal activity against all tested Campylobacter. The bactericidal effect was characterised as the production of organic acids in combination with probably production of an anti- Campylobacter protein. In a co-culture study of Campylobacter and Lactobacillus (P93), the culturability of Campylobacter was under the detection limit after 48 h of incubation. A chicken experiment is needed to further evaluate the effect of the promising probiotic bacteria against Campylobacter colonisation in chicken.

Cattle and sheep farms as reservoirs of Campylobacter.

This is a review of the natural Campylobacter colonization and transmission among ruminant livestock in the dairy farm environment. Using cultural detection methods and enumeration techniques the distribution of Campylobacter in ruminant animals at birth, on the farm, at slaughter and in the farm environment have been examined. Colonization and shedding rates are higher among young animals while patterns of shedding in adult animals may be seasonal. Stored and land-dispersed slurries provide a reservoir for scavenging birds and flies and a source for runoff. The dairy farm plays a significant role in the dissemination of Campylobacter subtypes that can cause disease in the human community. An understanding of the role of the dairy farm in the environmental cycle of Campylobacter is required in order to devise intervention strategies.

Campylobacter jejuni Binds Intestinal H(O) Antigen (Fucα1, 2Galβ1, 4GlcNAc), and Fucosyloligosaccharides of Human Milk Inhibit Its Binding and Infection

The most common cause of infant mortality is diarrhea; the most common cause of bacterial diarrhea is Campylobacter jejuni, which is also the primary cause of motor neuron paralysis. The first step in campylobacter pathogenesis is adherence to intestinal mucosa. We found that such binding was inhibited in vitro by human milk and, with high avidity, by alpha1,2-fucosylated carbohydrate moieties containing the H(O) blood group epitope (Fuc alpha 1,2Gal beta 1,4GlcNAc em leader ). In studies on the mechanism of adherence, campylobacter, which normally does not bind to Chinese hamster ovary cells, bound avidly when the cells were transfected with a human alpha1,2-fucosyltransferase gene that caused overexpression of H-2 antigen; binding was specifically inhibited by H-2 ligands (lectins Ulex europaeus and Lotus tetragonolobus and H-2 monoclonal antibody), H-2 mimetics, and human milk oligosaccharides. Human milk oligosaccharides inhibited campylobacter colonization of mice in vivo and human intestinal mucosa ex vivo. Campylobacter colonization of nursing mouse pups was inhibited if their dams had been transfected with a human alpha1,2-fucosyltransferase gene that caused expression of H(O) antigen in milk. We conclude that campylobacter binding to intestinal H-2 antigen is essential for infection. Milk fucosyloligosaccharides and specific fucosyl alpha1,2-linked molecules inhibit this binding and may represent a novel class of antimicrobial agents.

Effect of fermented feed on the susceptibility for Campylobacter jejuni colonisation in broiler chickens with and without concurrent inoculation of Salmonella enteritidis

Fermented liquid feed (FLF) protects broiler chickens against colonisation with Salmonella. While Campylobacter causes more disease cases in humans than Salmonella, the effect of FLF on Campylobacter was assessed. The fermented liquid feed is a moistened feed with a high number of lactobacilli, a high concentration of lactic acid, and a pH of 4. In three experiments Campylobacter was orally applied to individually housed 9-day-old broiler chickens. A significant reduction of susceptibility, as determined by cloacal swabs, was observed. At any moment where an animal has not started to shed Campylobacter yet, the probability to start shedding Campylobacter in a subsequent small time interval was nine times as high for the control chickens than for the animals that were fed FLF. FLF did not consistently change the Campylobacter colonisation level in the caeca. It was concluded that FLF could reduce the probability of introduction of Campylobacter in broiler flocks. In an experiment where some chickens were simultaneously inoculated with Salmonella enteritidis and Campylobacter, no interaction on susceptibility or caecal colonisation level was observed.

RAPD PCR Type of Campylobacter Isolates from Cecum Contents of Broiles Chickens

In this investigation we typed Campylobacter isolates by RAPD PCR from the cecum contents of broiler chickens obtained at a slaughterhouse in Shizuoka prefecture. Campylobacter was isolated from 91 (56.9%) out of 160 birds from five out of eight flocks . Of the five Campylobacter positive flocks, three flocks possessed multiple RAPD types of Campylobacter, and two flocks possessed a single type. In the flocks where multiple types of Campylobacter were obtained, all the birds were positive and multiple RAPD types of Campylobacter were isolated from individual broiler samples. In these flocks, multiple episodes of Campylobacter contamination may have occurred . On the other hand, the three Campylobacter negative flocks were considered to have had no Campylobacter contaminations . The differences in Campylobacter colonization of the flocks in this study may, at least in part, reflect the differences in the hygiene measures of the broiler houses in which these birds are raised.

Campylobacter colonization in poultry: sources of infection and modes of transmission.

Since its recognition as a human pathogen in the early 1970s, Campylobacter jejuni has now emerged as the leading bacterial cause of food-borne gastroenteritis in developed countries. Poultry, particularly chickens, account for the majority of human infections caused by Campylobacter. Reduction or elimination of this pathogen in the poultry reservoir is an essential step in minimizing the public health problem; however, farm-based intervention measures are still not available because of the lack of understanding of the ecological aspects of C. jejuni on poultry farms. Although Campylobacter is highly prevalent in poultry production systems, how poultry flocks become infected with this organism is still unknown. Many investigations indicate that horizontal transmission from environmental sources is the primary route of flock infections by Campylobacter. However, some recent studies also suggest the possibility of vertical transmission from breeder to progeny flocks. The transmission of the organism is not well understood, but it is likely to be through both vertical and horizontal transmission and may be affected by the immune status of the poultry host and the environmental conditions in the production system. Intervention strategies for Campylobacter infection in poultry should consider the complex nature of its transmission and may require the use of multiple approaches that target different segments of the poultry production system.

Recovery of Campylobacter from segments of the reproductive tract of broiler breeder hens.

Three groups of >60-wk-old broiler breeder hens were assessed for the presence of Campylobacter within segments of the reproductive tract. In the first group, after stunned, the hens were bled, scalded, and defeathered, the reproductive tracts were aseptically excised from 18 hens, six from each of three adjacent floor pens that were feces positivefor Campylobacter. The reproductive tract segments (infundibulum, magnum-isthmus, shell gland, vagina, and cloaca) were pooled by pen. In the second group, 10 individual hens were sampled from the pens; the reproductive tract was divided into the following segments: magnum, isthmus, shell gland, vagina, and cloaca. For the third group, hens were obtained from two commercial farms that had been determined to be feces positive for Campylobacter, and the reproductive tract was divided into five segments, as described for the second group. Segments of the reproductive tract were placed into sterile plastic bags and suspended 1:3 (w/v) in Bolton enrichment broth, and serial dilutions were plated (0.1 ml) onto Campy-Cefex agar. The agar places were incubated at 42 C for 24 hr in a microaerobic atmosphere. In group 1, the pooled reproductive tract segments for hens from pen A were Campylobacter positive for the shell gland, vagina, and cloaca; hens from pen B were positive for the cloaca only; and hens from pen C were positive for the magnum-isthmus and doaca. In the second group, 9 of 10 cloaca samples were Campylobacter positive. Commercial hens in group 3 had campylobacter-positive cloaca samples (12/12), vagina (10/12), shell gland (7/12), isthmus (2/12), and magnum (4/12). Campylobacter colonization of the reproductive tract of the hen could enable vertical transmission of Campylobacter from the hen to the chick.

Campylobacter colonization of the crops of newly hatched leghorn chicks.

We have studied colonization of crops in newly hatched leghorn chicks (a layer breed) by wild-type and mutant strains of Campylobacter jejuni. We established that the wild-type parent strain forms a stable population level within the crop and that the mutant strains will do likewise. Concentrations of mutant strains in the crop were usually below that of the wild-type parent strain and ranged from 10(3) to 10(5) colony-forming units. These results differ from results we have previously reported concerning cecal colonization, where these same mutant strains lacked colonizing ability. The present results, therefore, indicate that bacterial factors necessary for colonization of the crop are not the same as those needed for colonization of the cecum.

Campylobacter and Salmonella populations associated with chickens raised on acidified litter

Two commercially available acidifying litter treatments, aluminum sulfate (alum) and sodium bisulfate, were tested to determine their effects on Campylobacter and Salmonella colonization frequencies and populations associated with broilers raised on treated pine litter. To produce contaminated litter, broiler chicks were inoculated with two bacterial cocktails (multistrain mixtures of campylobacters and salmonellae) and were allowed to shed on the litter for about 6 wk. Upon bird removal, litter in duplicate pens was immediately treated with two levels of aluminum sulfate [3.63 or 7.26 kg/4.6 m2 (8 or 16 lb/50 ft2)] or sodium bisulfate 1.13 or 1.81 kg/4.6 m2 (2.5 or 4 lb/50 ft2)]; untreated pens served as controls. Immediately after treatment, day-of-hatch chicks were released in the pens. Frequency and populations of Campylobacter and Salmonella associated with ceca and whole carcass rinse (WCR) samples were determined for each duplicate pen at Weeks 1, 4, and 6. Both levels of the aluminum sulfate and sodium bisulfate litter treatments tested significantly (P < 0.05) reduced Campylobacter colonization frequency and populations in the ceca. Significantly, no Campylobacter was recovered from WCR samples associated with high level aluminum sulfate-treated pens at any time; although control pens were 95, 78, and 38% positive at Weeks 1, 4, and 6, respectively. Salmonella colonization frequency and populations in the ceca were not significantly decreased by any of the treatments investigated. Although effective pathogen control will most likely require a combination of interventions, acidifying treatment of litter in poultry production may serve as a means to help control Campylobacter and to reduce horizontal transmission of pathogens in broiler flocks.

Factors affecting intestinal colonisation of poultry by campylobacter and role of microflora in control

Although thermophilic campylobacters have sometimes caused disease in poultry, both in challenge studies and under field conditions, the organisms are usually carried asymptomatically in the alimentary tract of infected individuals. There is, however, a significant association between campylobacters in poultry and human enteritis. Properties of Campylobacter jejuni that are associated with intestinal colonisation in the bird are discussed. The organism is morphologically and physiologically well adapted to its ecological niche in the mucus-filled crypts of villi, but establishment and maintenance of colonisation involve a complex interaction between bacterium and host that has yet to be fully elucidated. Bacterial factors include the possession of intact, functional flagella and the type of flagellin expressed. Also, colonisation has been shown to depend on the expression of certain stress-response and virulence genes.Attempts to prevent or reduce campylobacter colonisation by establishing a competitive or antagonistic microflora in chicks have not always been successful, and possible reasons are considered. Some protection was obtained with bacteria such as mucin-utilising coliforms, but the protective potential of these organisms appears to be limited. In other studies, the natural occurrence of colonisation resistance has been demonstrated in broilers and its development followed. Experience suggests that the phenomenon depends on the presence of strictly anaerobic bacteria that have yet to be isolated and identified.

114. Use of the oral model of Campylobacter colonisation in chickens to assess the effects of growth promoter and therapeutic antibiotics

114. Use of the oral model of Campylobacter colonisation in chickens to assess the effects of growth promoter and therapeutic antibiotics

Pathogenesis of enteric Campylobacter infection.

Campylobacter jejuni and related species are important human pathogens, causing acute human enterocolitis, and they are the most common cause of food-borne diarrhoea in many industrialized countries. Previous infection with certain strains of C. jejuni is also linked with the development of the neurological disorder Guillain-Barre syndrome (GBS). Despite its importance as a human pathogen, relatively little is understood of the mechanisms of C. jejuni-associated disease. The recent release of the complete genome sequence of C. jejuni strain NCTC 11168, together with new strategies for random and directed mutagenesis, have allowed a better insight into some of the genetic determinants of C. jejuni virulence. In this review current knowledge on the pathogenesis of C. jejuni infection is summarized, and possible directions of future research indicated.

Study of the infectivity of saline-stored Campylobacter jejuni for day-old chicks.

The culturability of three Campylobacter jejuni strains and their infectivity for day-old chicks were assessed following storage of the strains in saline. The potential for colonization of chicks was weakened during the storage period and terminated 3 to 4 weeks before the strains became nonculturable. The results from this study suggest that the role of starved and aged but still culturable campylobacters may be diminutive, but even more, that the role of viable but nonculturable stages in campylobacter epidemiology may be negligible. Even high levels of maternally derived anti-campylobacter outer membrane protein serum antibodies in day-old chicks did not protect the chicks from campylobacter colonization.

Comparison of Mucosal Competitive Exclusion and Competitive Exclusion Treatment to Reduce Salmonella and Campylobacter spp. Colonization in Broiler Chickens

Control of Salmonella spp. during the earliest phases of broiler production may provide the best opportunity to reduce human pathogens on processed broiler carcasses. Application of the “Nurmi concept” has been demonstrated to be an effective means in reducing Salmonella colonization among broiler chicks. In 1989, Aho et al. developed a competitive exclusion (CE) culture for control of Salmonella spp., whereas a mucosal competitive exclusion culture (MCE) developed in the United States was originally created to control Campylobacter colonization (Stern et al., 1995). The major differences in the two patents were the higher level of anaerobic culture required, the degree of epithelial scraping and washing of the ceca, media used for subculturing, and the culture incubation temperatures (35 C vs. 42 C). The CE and MCE were compared for efficacy in reducing Salmonella and Campylobacter colonization in broiler chicks. Nine adult birds (three for each of three replicates) were slaughtered, and each of a bird's paired ceca were used to produce corresponding antagonistic microflora, which were administered to day-of-hatch chicks. The chicks (a total of 210) were challenged 24 h later with Salmonella and Campylobacter and were killed 1 wk later, and levels of the pathogens were determined. Ninety CE-treated birds were significantly more colonized by Salmonella typhimurium than those 90 chicks treated with the MCE microflora (3.97 log 10 cfu/g cecal contents vs. 1.25 log 10 cfu/g cecal contents). Also, Campylobacter spp. colonization of these birds was significantly higher for CE-treated birds when compared with MCE-treated birds (6.96 log 10 cfu/g cecal contents vs. 5.03 log 10 cfu/g cecal contents). These results can be useful in developing intervention strategies to reduce chicken colonization by Salmonella and Campylobacter.

Antimicrobial susceptibilities of Campylobacter strains isolated from broilers in the southern part of Japan from 1995 to 1999.

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.

National Surveillance of Campylobacter in Broilers at Slaughter in Denmark in 1998

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.

Diminution of Campylobacter Colonization in Neonatal Pigs Reared Off-Sow

Pigs may be a natural reservoir of Campylobacter and can be colonized as early as 24 h after birth. The purpose of the present study was to evaluate what effect early removal of piglets from Campylobacter-positive sows has on Campylobacter prevalence in neonates. In two trials, piglets were removed from sows within 24 h of birth and were reared in nurseries isolated from sows for 21 days. From the neonates rectal swabs were cultured for Campylobacter, and Campylobacter status of the isolated piglets was compared to that of littermates reared on sows. The nurseries consisted of wire-floored farrowing crates that were equipped with heaters and self-feeders. In trial I, the Campylobacter prevalence in nursery-reared piglets was 13 of 14 on day 2 and 0 of 14 on day 20. Campylobacter prevalence in the sow-reared piglets was 8 of 9 from days 2 to 20. In trial II, 12 of 29 on day 2, and 5 of 26 on day 20, of the nursery-reared piglets were culture positive for Campylobacter. For the sow-reared piglets, Campylobacter prevalence was 7 of 15 on day 1 and 15 of 15 (100%) on day 20. These data suggest that successful permanent colonization of the gut by Campylobacter is probably related to constant exposure of piglets to Campylobacter-positive feces. Campylobacter prevalence may be diminished in neonates that are reared off-sow in isolated nurseries.

Study in ovo immunisation with flagellin and whole cell protein antigens of Campylobacter jejuni in chickens

In ovo immunisation of chickens with flagellin and whole cell protein antigens of Campylobacter jejuni was examined to determine Campylobacter infection. Four groups of embryonated chicken eggs (10 eggs per group) were immunised in ovo at day 17 of incubation and booster was given at 7 days post-hatch. Group I was immunised in ovo and oral booster with whole cell protein of C. jejuni , group II was immunised in ovo and oral booster with C. jejuni flagellin protein, group III was immunised in ovo and intraperitoneal booster with whole cell, and group IV was treated as control. The humoral immune responses were determined by enzyme-linked immunosorbent assay (ELISA) and the mucosal immune responses were examined by a direct fluorescent histology antibody technique. Immunised chickens of Group I, II, and III shown to have higher antibody titers than those of control chickens (group IV). The titres of anti-campylobacter antibodies of all isotypes in serum, bile, and intestinal scrapping after challenge were not significantly different in all groups. In addition, when immunised chickens were orally challenged with a homologous strain of viable C. jejuni organism, the chickens remained infected throughout the experiment based on cloacal swabs and caecal contents. These findings indicated that although in ovo immunisation resulted in increasing of the mucosal and humoral immune responses in chickens, it is not strong enough to protect the Campylobacter colonisation in the intestinal tract. Key words : In ovo immunisation, Campylobacter jejuni , whole cell, flagellar, chickens

Dose Response and Organ Invasion of Day-of-Hatch Leghorn Chicks by Different Isolates of Campylobacter jejuni

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.

Generation of a superoxide dismutase (SOD)-deficient mutant of Campylobacter coli: evidence for the significance of SOD in Campylobacter survival and colonization.

The microaerophilic nature of Campylobacter species implies an inherent sensitivity towards oxygen and its reduction products, particularly the superoxide anion. The deleterious effects of exposure to superoxide radicals are counteracted by the activity of superoxide dismutase (SOD). We have shown previously that Campylobacter coli possesses an iron cofactored SOD. The sodB gene of C. coli UA585 was insertionally inactivated by the site-specific insertion of a tetO cassette. Organisms harboring the inactivated gene failed to produce a biologically functional form of the enzyme. While the ability of this mutant to grow in aerobic conditions was unchanged relative to the parental strain, its survival was severely compromised when nongrowing cells were exposed to air. Accordingly, the SOD-deficient mutant was unable to survive for prolonged periods in model foods. Furthermore, inactivation of the sodB gene decreased the colonization potential in an experimental infection of 1-day-old chicks. In contrast, strain CK100, which is deficient in catalase activity, showed the same survival and colonization characteristics as the parental strain. These results indicate that SOD, but not catalase, is an important determinant in the ability of C. coli to survive aerobically and for optimal colonization within the chicken gut.