Natural Occurrence of Campylobacter Species,Salmonella Serovars,and Other Bacteria in Unabsorbed Yolks of Market-Age Commercial Broilers

In the developing avian embryo, the main energy source is the yolk. Toward the end of the incubation period, the remaining yolk sac is internalized into the abdominal cavity. At hatch, the remaining yolk comprises 20% of the chick's BW and provides the nutrients needed for maintenance. Posthatch, chicks rapidly initiate the transition from yolk dependence to the utilization of exogenous feed. However, at present, it is not known what types of bacteria are found to be associated with unabsorbed yolk sacs from market-age broilers. For Experiment 1, one hundred 6-wk-old defeathered broiler carcasses were obtained from a commercial processing facility during each of 3 visits. In the second experiment, one hundred 8-wk-old defeathered broiler carcasses were obtained from a different commercial processing plant on 4 separate occasions. For both experiments, each carcass was aseptically opened and inspected for the presence of an unabsorbed yolk sac. Three to 5 carcasses containing a free-floating yolk sac (within the abdominal cavity) and the yolk stalk (without a yolk sac) and 3 to 5 carcasses containing an attached yolk and yolk stalk from each repetition were randomly selected and analyzed for levels and types of total aerobic bacteria (APC), Enterobacteriaceae (ENT), and for the presence of Campylobacter spp. and Salmonella serovars. The APC ranged from log 3.3 to >log 6.0, and the ENT ranged from log 2.8 to >log 6.0. Staphylococcus spp. and Streptococcus spp. were the predominant organisms in APC, whereas Escherichia coli and Hafnia alvei were found to comprise the ENT. Campylobacter spp. was found in 29% of the yolk stalks, 32% of the attached yolk sacs, and 13% of the free-floating yolk sacs. All Campylobacter isolates were determined to be Campylobacter jejuni, except for 1 attached yolk and yolk stalk, which was Campylobacter coli. Salmonella serovars were found in 26% of the yolk stalks, 48% of the attached yolk sacs, and 23% of the free-floating yolk sacs, and the majority of Salmonella isolates were Salmonella Typhimurium. The significance of these bacterial reservoirs and carcass contamination during processing is yet to be determined.     

Characterization of Campylobacter jejuni in large-billed crows (Corvus macrorhynchos) in Tochigi prefecture,Japan

As free-living crows are a potential source of Campylobacter infections in broilers and cattle, we characterized Campylobacter spp. isolated from crows using multilocus sequence typing and antimicrobial susceptibility testing. We obtained 82 samples from 27 birds captured at seven different times using a trap set in Tochigi prefecture, Japan. Campylobacter jejuni was isolated from 55 (67.1%) of the 82 samples and classified into 29 sequence types, of which 21 were novel. Tetracycline and streptomycin resistance rates were 18.2% and 3.6%, respectively. These results show that most types of C. jejuni infecting crows differ from those isolated from humans, broilers, and cattle. Thus, the importance of free-living crows as reservoirs of Campylobacter infections in broilers and cattle may be limited.     

Wild Bonelli’s eagles (Aquila fasciata) as carrier of antimicrobial resistant Salmonella and Campylobacter in Eastern Spain

Wild birds have repeatedly been found to be involved in the dissemination of enteric bacterial pathogens in the environment. The aim of this study was to determine the occurrence of Salmonella and Campylobacter as well as the antimicrobial resistance in wild Bonelli’s eagles nestlings in Eastern Spain. In addition, we compared the efficiency of two sampling methods (fresh faecal samples from nest and cloacal swabs from nestlings) for detection of both bacteria. A total of 28 nests with 45 nestlings were analysed. In the nest, Salmonella occurrence was 61 ± 9.2%, while Campylobacter occurrence was 11 ± 5.8% (p < 0.05). In the nestlings, Salmonella occurrence was 36 ± 7.1%, while Campylobacter occurrence was 11 ± 4.7% (p < 0.05). Eight Salmonella serovars were identified, and the most frequently isolated were S. Enteritidis, S. Typhimurium, S. Houston, and S. Cerro. Only one Campylobacter species was identified (C. jejuni). Regarding antimicrobial resistance, the Salmonella strains isolated were found to be most frequently resistant to ampicillin and to tigecycline; however, the sole Campylobacter strain recovered was multidrug resistant. In conclusion, this study demonstrated that wild Bonelli’s eagles nestlings are greater carriers of Salmonella than of Campylobacter. Both Salmonella and Campylobacter isolates exhibited antimicrobial resistance. In addition, faecal samples from nests were most reliable for Salmonella detection, while cloacal swab from nestlings were most reliable for Campylobacter detection.     

Routes of transmission of Salmonella and Campylobacter in breeder turkeys

Salmonella and Campylobacter are frequent colonizers of the intestinal tracts of poultry and have often been associated with human foodborne illness. The entry, transmission, and prevalence of both pathogens have been extensively studied in chickens but little information is available for turkeys. This project monitored turkey breeder hens and toms from d of hatch to 65 wk of age with the objective of determining routes of transmission for Salmonella and Campylobacter throughout the turkey production cycle. Breeder poults were separated by sex and then into 2 groups (control and inoculated) for each sex. The inoculated group was orally gavaged with marker strains of both Salmonella and Campylobacter. The inoculated groups (toms and hens) were placed on the opposite side of a growout house from the uninoculated groups. Fecal samples, intestinal samples and organs, feed, drinkers, and potential vectors such as insects and mice, were analyzed at different times until 65 wk. Monitoring showed that Campylobacter spread rapidly and cross-contaminated turkeys throughout the growout house. For both Salmonella and Campylobacter, naturally occurring strains that were first isolated in control groups at wk 3 and 4, respectively, outcompeted marker strains several wk post inoculation and persisted in the flock. The most common naturally occurring strains were C. jejuni (tetracycline resistant), C. coli (kanamycin resistant), and S. Agona. Campylobacter and Salmonella also were isolated from flies and from a mouse, confirming the importance of proper pest control and biosecurity to reduce the spread of the bacteria.     

PET AND CAPTIVE BIRDS AS POTENTIAL RESERVOIRS OF ZOONOTIC BACTERIA

Thermophilic Campylobacter spp. and Salmonella spp. are zoonotic bacteria, commonly harbored in the enteric tract of avian species. This survey aimed at verifying the presence of these microorganisms in a heterogeneous Italian population of pet birds and captive birds of prey (e.g., Passeriformes, Psittaciformes, Accipitriformes, Falconiformes, and Strigiformes) that live in close contact with humans. A total of 151 individuals were tested for thermophilic Campylobacter spp. and 444 for Salmonella spp. Six C. jejuni and one S. Livingstone were isolated from birds of prey: 4 Accipitriformes (2 Buteo regalis, 2 Parabuteo unicinctus), 1 Falconiformes (Falco peregrinus) and 1 Strigiformes (Strix aluco) were positive for C. jejuni, and 1 Falconiformes (Falco peregrinus) for S. Livingstone. Five C. jejuni strains were genotyped by Multilocus Sequence Typing (MLST) and identified as ST 2116, assigned to ST-353 CC. Results of this study suggest that these microorganisms are not common inhabitants of the digestive tract of pet birds and captive birds of prey, but occasional findings. However, as potential reservoirs of zoonotic bacteria, pet birds should be monitored in order to preserve human health.     

Occurrence of foodborne bacteria in Alberta feedlots

The occurrence of generic Escherichia coli, E. coli O157, Salmonella, and Campylobacter in cattle manure, beef carcasses, catch basin water, and soils receiving manure application was determined in 21 Alberta feedlots. In cattle manure, generic E. coli (98%, 2069/2100) and Campylobacter (76%, 1590/2100) were frequently detected; E. coli O157 (7%, 143/2100) and Salmonella (1%, 20/2100) were less frequently detected. Samples from beef carcasses in the cooler following Hazard Analysis Critical Control Point interventions yielded only 1 isolate each of generic E. coli and Campylobacter (1/1653) and no Salmonella (0/1653). Catch basin water specimens were positive for generic E. coli in both the spring (62%, 13/21) and the fall (52%, 11/21). Other bacteria were detected only in the spring water specimens, including E. coli O157 (29%, 6/21), Salmonella (5%, 1/21), and Campylobacter (52%, 11/21). Generic E. coli was frequently isolated from soil specimens (30%, 27/88), but E. coli O157 was not found in soil samples obtained in the spring and was only occasionally detected in the fall samples (9%, 3/32). Salmonella were occasionally found in the soil specimens collected in the spring (3%, 2/56), but not in the fall season (0/32). Campylobacter jejuni was frequent in cattle manure (66%, 1070/1623), but rare in carcass and environmental samples. E. coli O157 and Salmonella were rarely detected in cattle or the environment. Generic E. coli and Salmonella were rarely detected on carcasses.     

Genetic diversity and antimicrobial resistance of Campylobacter and Salmonella strains isolated from decoys and raptors

Infections caused by thermotolerant Campylobacter spp. and Salmonella spp. are the leading causes of human gastroenteritis worldwide. Wild birds can act as reservoirs of both pathogens. A survey was carried out to determine the prevalence, genetic diversity and antimicrobial resistance of thermotolerant Campylobacter and Salmonella in waterfowl used as decoys and wild raptors in Andalusia (Southern Spain). The overall prevalence detected for Campylobacter was 5.9% (18/306; CI_95%: 3.25–8.52) in decoys and 2.3% (9/387; CI_95%: 0.82–3.83) in wild raptors. Isolates were identified as C. jejuni, C. coli and C. lari in both bird groups. Salmonella was isolated in 3.3% (10/306; CI_95%: 2.3–4.3) and 4.6% (18/394; CI_95%: 3.5–5.6) of the decoys and raptors, respectively. Salmonella Enteritidis and Typhimurium were the most frequently identified serovars, although Salmonella serovars Anatum, Bredeney, London and Mikawasima were also isolated. Pulsed-field gel electrophoresis analysis of isolates showed higher genetic diversity within Campylobacter species compared to Salmonella serovars. Campylobacter isolates showed resistance to gentamicin, ciprofloxacin and tetracycline, while resistance to erythromycin and tetracycline was found in Salmonella isolates. The results indicate that both decoys and raptors can act as natural carriers of Campylobacter and Salmonella in Spain, which may have important implications for public and animal health.     

Evaluation of recovery of Salmonella from trachea and ceca in commercial poultry

Unpublished data from our laboratory suggest that the respiratory tract may be a viable portal of entry for Salmonella infection. Further, field reports have indicated that tracheal sampling can be a sensitive tool for monitoring for Salmonella incidence in commercial flocks. In the present study we conducted a series of field trials in North and South America to evaluate the association between cecal and tracheal recovery of Salmonella in chickens and turkeys from commercial flocks. Environmental humidity and temperature were measured to evaluate their effects on frequency of isolation from the organs. Salmonella was recovered from tracheal samples in all trials. In 3 of the 4 trials in which both trachea and ceca were sampled, the incidence of Salmonella recovery was higher in tracheal samples. Though Salmonella was not recovered from ceca in trial 2, 5% of liver and spleen samples indicated infection. Environmental conditions were not associated with incidence of Salmonella recovery. These data suggest that tracheal contamination can be a good indicator of Salmonella infection under commercial poultry conditions.     

Evidence of cross-contamination by Campylobacter spp. of broiler carcasses using genetic characterization of isolates

Campylobacter is recognized as one of the leading cause of gastroenteritis worldwide, and is frequently isolated from the small intestines and ceca microflora of chickens. Twenty-one out of 81 Campylobacter-positive poultry flocks were selected to evaluate the genetic diversity of Campylobacter isolates and to study the distribution of genotypes among flocks. Campylobacter isolates recovered from chicken carcasses and ceca were analyzed by pulsed-field gel electrophoresis (PFGE). Little diversity was found among Campylobacter strains isolated from a given carcass, with a maximum of 2 different genotypes being present. However, at flock level, as many as 4 different profiles were observed. Typing of strains showed that most strains isolated from ceca were similar to those isolated from corresponding broiler carcasses. A total of 39 different macrorestriction profiles were observed, with evidence of Campylobacter cross-contamination among broiler flocks in Quebec slaughterhouses. Surprisingly, some flocks shared related genotypes both with and without sharing similar rearing practices. Existence of such cross-contamination must be considered to in developing strategies to control Campylobacter in chickens, and to avoid bacteria contamination of noncolonized flocks. Further typing studies of Campylobacter found in hatcheries, farm environment, and crates or trucks in Quebec might be helpful in elucidating the kinetics of broiler chicken Campylobacter contamination.     

Rosemary oil,clove oil,and a mix of thyme-orange essential oils inhibit Salmonella and Campylobacter in vitro

The demand for foods that are free of pathogens and chemical residues has increased interest in the use of plant-based products as natural antimicrobials. Essential oils (EO) from plants are natural compounds that have been shown to have antimicrobial properties against food-borne pathogens. The objective of the current study was to determine the ability of various concentrations of 4 selected EO to inhibit Salmonella enterica (3 different serovars and a cocktail of all 3) and Campylobacter (2 strains of Campylobacter jejuni, one strain of Campylobacter coli, and a cocktail of all 3). The disc diffusion method was used to screen the oils of thyme, orange, rosemary, and clove oil. The minimum inhibitory concentration or minimum bactericidal concentration of the EO was determined using a 2-fold broth dilution method at concentrations ranging from 0.0008 to 1.000% (vol/vol). Two independent experiments were performed. Zones of inhibition (ZI) were expressed in millimeters and concentrations were expressed in percentages. All the oils demonstrated antibacterial activity against the strains tested. However, thyme oil demonstrated the strongest inhibitory activity than other oils against Salmonella (ZI of 18.5 mm). In general, Campylobacter was more susceptible to the antibacterial activity of EO, with plates containing thyme or clove oil showing no growth. Orange oil was also highly effective on Campylobacter, with a mean ZI of 17.5 mm. The least expensive treatment effective against both Salmonella and Campylobacter was a combination of 100% concentrations of thyme and orange oil combined on a 50:50 proportion. Tested on the same strains of bacteria, the thyme-orange combination (TOC) had a mean ZI of 20.5 mm for Salmonella and 21.3 mm for Campylobacter. Thyme-orange combination demonstrated a synergetic effect against Salmonella, but no such effect was noticed for Campylobacter. On average, 0.14% TOC was required to inhibit both pathogens. Hence, TOC can be considered as a potential antimicrobial for future studies on food systems.     

Comparison of methods for the detection ofSalmonella in poultry

The aim of this study was to compare 2 testing methods forSalmonella in poultry. One-day-old specific-pathogen-free chicks were infected via crop installation with aSalmonella test strain (Salmonella Enterititis phage type 4; Bundesintitut für gesundheitlichen Verbraucherschutz und Veterinärmedizin-No. 01–00554; nalidixic acid resistant). Samples were collected at 7 sample occasions to redetect the agent from the animals and the environment. Using conventional techniques and PCR, the test strain was successively detected in the animals as well as in the environment of the flocks. In comparison, PCR was more effective. First positive findings were obtained from cloacal swabs at the third sampling occasion. Most frequentlySalmonella was obtained from ceca and from spleen samples, indicating that these 2 organs are most suitable forSalmonella testing. Cloacal swabs were positive earlier; however, ceca and spleen samples were positive more consistently. Conventional methods as well as PCR were suitable for detection ofSalmonella.     

Prevalence and antimicrobial resistance of Campylobacter and Salmonella in layer flocks in Honshu,Japan

Campylobacter and non-typhoidal Salmonella are the major causes of bacterial gastrointestinal infections in humans. Although antimicrobial therapy is typically not recommended in many cases of these infections, it may be life-saving in patients with severe symptoms. Since chicken eggs and meat derived from layers are destined for human consumption, we investigated the prevalence and antimicrobial resistance of these two bacterial genera in 82 layer flocks at chicken processing plants in Honshu, Japan. Campylobacter was isolated from 77 flocks (93.9%). Resistance to ampicillin, tetracycline, and ciprofloxacin was documented in 42.3 (30/71), 16.9 (12/71), and 14.1% (10/71) of Campylobacter jejuni, respectively. Multilocus-sequence typing identified ST4389 and ST5262 as the most frequent C. jejuni sequence types. In C. coli, resistance to ampicillin, tetracycline, and ciprofloxacin was found in 20.0 (7/35), 20.0 (7/35), and 25.7% (9/35), respectively. The most frequent sequence type in C. coli was ST8292. Erythromycin resistance was not observed among Campylobacter species. Salmonella was isolated from 14 flocks (17.1%). The two most frequent serovars were Salmonella Corvallis and S. Braenderup. Neither S. Enteritidis nor S. Infantis were isolated. Streptomycin resistance was observed in six isolates (26.1%), and all isolates were susceptible to cefotaxime and ciprofloxacin. Thus, chicken eggs and meat derived from layers are possible sources of these bacterial infections in humans. The antimicrobial susceptibility of these isolates was maintained, reflecting restrictions on the use of antimicrobial agents on layers.     

The isolation and characterization of Campylobacter jejuni bacteriophages from free range and indoor poultry

Six hundred and sixty one samples – primarily fresh chicken faeces – were processed to isolate wild type Campylobacter jejuni bacteriophages, via overlay agar methods using C. jejuni NCTC 12662. The aims of this study were to isolate and purify bacteriophages and then test for their ability to lyse field strains of C. jejuni in vitro. Of all samples processed, 130 were positive for bacteriophages. A distinct difference was observed between samples from different poultry enterprises. No bacteriophages could be isolated from indoor broilers. The majority of bacteriophages were isolated from free range poultry – both broilers and egg layers. Bacteriophages were purified and then selected for characterization based on their ability to produce clear lysis on plaque assay, as opposed to turbid plaques. Two hundred and forty one C. jejuni field isolates were tested for sensitivity to the bacteriophages. Lysis was graded subjectively and any minimal lysis was excluded. Using this system, 59.0% of the C. jejuni isolates showed significant sensitivity to at least one bacteriophage. The sensitivity to individual bacteriophages ranged from 10.0% to 32.5% of the C. jejuni isolates. Five bacteriophages were examined by electron microscopy and determined to belong to the Myoviridae family. The physical size, predicted genetic composition and genome size of the bacteriophages correlated well with other reported Campylobacter bacteriophages. The reasons for the observed difference between indoor broilers and free range poultry is unknown, but are postulated to be due to differences in the Campylobacter population in birds under different rearing conditions.     

Comparison of Cape Town and Skirrow's <Emphasis Type="Italic">Campylobacter</Emphasis> isolation protocols in humans and broilers in Morogoro,Tanzania

Comparison of Cape Town and Skirrow's protocols used in isolation of Campylobacter in humans and broilers was carried out in a cross-sectional study in Morogoro, Tanzania. A total of 176 and 158 human stool and broiler intestinal samples were collected, respectively. While human stool samples were collected from selected health centers, broiler intestinal samples were obtained from selected farms and chicken markets. Samples were inoculated and cultured in duplicate using two protocols and prevalence of Campylobacter were established. In humans, the prevalence of Campylobacter isolates was significantly higher (P < 0.001) (21.6%) with Cape Town protocol than Skirrow's method (9.1%). Similarly, a higher prevalence (P < 0.05) in broilers was recorded in Cape Town protocol (77.8%) than Skirrow's method (66.5%). There was a moderate (0.53) Kappa test of agreement between Skirrow's and Cape Town protocols for human samples and substantial agreement (0.72) for broiler samples. This demonstrates that Cape Town protocol is superior over the Skirrow's protocol in Campylobacter isolation. Campylobacter jejuni, Campylobacter coli and Campylobacter lari were the Campylobacter spp. isolated. In humans, C. jejuni accounted for 92.1% and 87.5% of all positive samples with Cape Town and Skirrow's protocols, respectively. In broilers, C. jejuni was isolated at 91.1% and 92.5% of all species obtained with Cape Town and Skirrow's protocols, respectively. This shows that C. jejuni is the common species that may be circulating from either broilers to humans or other animals and vice versa. The present study has introduced Cape Town protocol in Tanzania for Campylobacter isolation from human and animal samples, which is expected to improve the isolation of Campylobacter species. Cape Town protocol may also be a good alternative for use in routine isolation of Campylobacter.     

Detection and genotypic differentiation of Campylobacter jejuni and Campylobacter coli strains from laying hens by multiplex PCR and fla-typing

In total, 26 Campylobacter (C.) strains, isolated from liver, spleen, caecal or jejunal content of laying hens from different flocks were examined. In these flocks a drop in egg production, an increasing mortality and livers with whitish-grey lesions as post-mortem finding were observed. Suspected Campylobacter colonies were differentiated using a modified m-PCR in 13 Campylobacter jejuni and 13 Campylobacter coli strains. All isolates were characterised by typing of the flaA and flaB gene each with two restriction enzymes. To compare the four different profiles for all strains an artificial “fla-type” was generated. Different and identical fla-types of C. jejuni and C. coli were recovered from both intestinal and extra-intestinal organs of the laying hens and even from individual birds. One significant observation is that some fla-types of C. jejuni or C. coli were detected in intestinal and systemic sites but not all fla-types of both species appeared to be equally able to invade internal organs.     

Impact of added sand on the recovery of Salmonella,Campylobacter, Escherichia coli,and coliforms from prechill and postchill commercial broiler carcass halves

Salmonella and Campylobacter are often associated with raw poultry products and continue to be leading causes of food-borne gastroenteritis in the United States. As a result, the presence of these organisms on broiler carcasses is monitored on a routine basis. Abrasive rinsing methods (e.g., adding glass beads) have been shown to increase the level of bacteria recovered from carcasses or carcass parts. The objective of this study was to evaluate the addition of sand to the rinse on bacterial enumeration and the prevalence of Salmonella and Campylobacter recovered from broiler carcasses. During each of 4 replications, 6 prechill and 6 postchill broiler carcasses were collected from a commercial processing plant. All carcasses were split along the dorso-ventral midline. Carcass halves were rinsed in buffered peptone water, whereas the companion half was rinsed in buffered peptone water with sterile sand added. All carcass halves were rinsed for 1 min and the rinsate was collected. Salmonella, coliforms, and Escherichia coli were enumerated and the prevalence of Salmonella and Campylobacter was determined. Salmonella and Campylobacter were isolated from 17 and 50% of the carcass halves, respectively. There was no significant (P > 0.05) difference in Salmonella or Campylobacter prevalence from carcass halves rinsed with or without sand. The addition of sand to the rinse had no effect on the number of Salmonella, coliforms, or E. coli recovered from prechill or postchill carcass halves. These results show that adding sand to the rinse liquid did not improve the recovery of bacteria present on the carcass in either moderate (2.6 log₁₀ cfu/mL rinsate) or low numbers (<3 cfu/mL of rinsate).     

Multilocus sequence typing of Campylobacter jejuni from broilers

Campylobacter jejuni isolates from a national Swedish Campylobacter monitoring in broilers were characterized by multilocus sequencing typing (MLST) in order to study the genetic diversity of this bacterial population. Isolates were initially characterized by pulsed-field gel electrophoresis (PFGE). One hundred were chosen for MLST genotyping. PFGE identified 69 distinct types compared to 44 different sequence types (STs) identified with MLST. Eighteen STs had not been described previously, while the remaining 26 STs were assigned to previously known clonal complexes. The majority of isolates were of genotypes noted in broilers and in humans in earlier studies. However, three clonal complexes, ST-206 complex, ST-677 complex and ST-1034 complex, previously associated with wild bird and environmental samples, were among the genotypes found. This study shows that most of the Swedish broiler isolates were of genotypes noted as common in broilers. However, it also highlights the potential influence of environmental sources on the broiler C. jejuni genotypes.     

Prevalence and antibiotic susceptibility of thermophilic Campylobacter isolates from free range domestic duck (Cairina moschata) in Morogoro municipality, Tanzania

Prevalence and antibiotic susceptibility of thermophilic Campylobacter isolated from free-ranging ducks was determined in Morogoro Municipality, Tanzania. Ninety intestinal contents from ducks were screened for thermophilic Campylobacter using Skirrow’s protocol. Of the Campylobacter jejuni isolates, 50 were tested for sensitivity to 12 antibiotics. Overall prevalence of thermophilic Campylobacter was 80%. The prevalence of Campylobacter in adult ducks (91.3%) was significantly (p?<?0.05) higher than ducklings (68.2%). The isolation rate of C. jejuni (81.9%) was significantly (P?<?0.001) higher than C. coli (18.1%). All C. jejuni isolates were susceptible to streptomycin, nitrofurantoin and amikacin. Forty eight percent, 74% and 82% of isolates were resistant to cefuroxime sodium, tetracycline and ampicillin respectively. Between 20–50% of isolates were resistant to erythromycin, gentamicin, cloxacillin and amoxicillin. Norfloxacin and ciprofloxacin had lower C. jejuni resistance of 10% and 16% respectively. C. jejuni isolates from adult ducks showed significantly higher rates of resistance (p?<?0.05) to most antibiotics than did duckling isolates. High prevalence of thermophilic Campylobacter in ducks could be of public health significance in Morogoro municipality. The observed multidrug resistance in this study poses a threat of transfer of antibiotic resistance to human pathogens because of the close contact between ducks and human.     

Detection ofCampylobacter in 100 commercial flocks–Evaluation of plating media and filtration method

Campylobacter is a natural member of the gut microflora in many commercial broilers and as such can become a contaminant on edible surfaces during processing. Culturing gut contents or feces can be a means to determine flock status prior to live-haul. The wide variety of non-Campylobacter background bacteria in these complex samples contaminates growth media and can make it very difficult to isolateCampylobacter. Over the course of 17 months, we cultured cecal contents from 100 different broiler flocks. For the last 50 flocks, we tested 3 selective plating media with and without the additional selection of a 0.45-μm filter for detection ofCampylobacter from cecal contents. Furthermore, from the last 50 flocks we also collected and cultured carcass rinse samples. Growth media tested included: Campy–Cefex Agar, Campy–Line Agar, and RF-Campylobacter jejuni/coli agar. About half (52%) of the 100 tested flocks were positive forCampylobacter; positive flocks were detected during each month of the year. Overall, theCampylobacter status of cecal contents from one carcass was predictive of the status of a carcass rinse from the same flock. Placing a complex sample such as cecal contents onto a 0.45-μm filter laid on top of the plating medium improved the detection ofCampylobacter by eliminating non-Campylobacter background colonies. All media allowed for detection ofCampylobacter from less complex carcass rinse samples without filtering. However, Campy–Cefex agar had higher numbers of competing bacterial colonies than did Campy–Line agar or RF-Campylobacter jejuni/coli agar.     

Molecular detection of Campylobacter species and Cytolethal distending toxin isolated from chicken livers in Tabriz

Introduction and purpose: Campylobacter jejuni and coli are zoonotic bacteria commonly associated With human diarrhea and usually transmit through consumption of meat and poultry contaminated products such as heart and liver. Cytolethal distending toxin (cdt) in Campylobacter spp. is among the significant virulence factors of these bacteria in the intestine. The purpose of this study was to determine the prevalence of Campylobacter spp. and presence of cdt genes among isolated bacteria. Materials and methods: In this cross sectional study, 100 chicken livers were examined. Detection, bacterial enumeration and isolation of Campylobacter spp. was done using Campylobacter selective agar media containing Campylobacter growth supplement, gram staining, catalase and oxidase production, hippurate hydrolysis and PCR molecular technique. Also the presence of cdt genes were detected using PCR assay. Results: From 100 studied liver samples, 43 were contaminated with Campylobacter spp. Among them 31(72 %) samples had Campylobacter jejuni and 12 (28 %) had Campylobacter coli. All Campylobacter jejuni isolates contained cdtA ،cdtB and cdtC genes. However, all of these genes detected in 9 (75 %) of isolated coli. Conclusion: The results of this study showed that great percentages of chicken livers in Tabriz were contaminated with Campylobacter.