Incidence and tracking of Clostridium perfringens through an integrated broiler chicken operation

Clostridium perfringens has been shown to be widespread in the broiler chicken hatchery, grow-out, and processing operations. In a previous study, ribotypes of certain strains of C. perfringens isolated from processed chicken carcasses were shown to match ribotypes isolated from paper pad lining trays used to transport commercial chicks from the hatchery to the grow-out facility on the farm. These results suggest that C. perfringens contaminating the processed product could originate from facilities in the integrated poultry operation prior to grow out. In this study, samples were collected from the breeder farm, hatchery, previous grow-out flock, during grow out and after processing. In the first trial, C. perfringens was recovered from the breeder farms, the hatchery, previous grow-out flock, grow-out flock at 3 weeks of age, grow-out flock at 5 weeks of age, from processed carcasses, and from the breeder farm after processing in 4%, 30%, 4%, 0%, 2% and 16%, and 4% of the samples, respectively. In the second trial, the incidence of C. perfringens in samples collected from breeder farms, the hatchery, previous grow-out flock, grow-out flock at 3 weeks of age, grow-out flock at 5 weeks of age, and fromprocessed carcasses was 38%, 30%, 32%, 8%, 4%, and 8%, respectively. The genetic relatedness of the isolated strains as determined by ribotyping suggests that C. perfringens may be transmitted between facilities within the integrated broiler chicken operation.     

Multilevel analysis of environmental Salmonella prevalences and management practices on 49 broiler breeder farms in four south-eastern States, USA

A two-part serial survey of 49 broiler breeder farms was conducted in four south-eastern states: Arkansas, Alabama, Georgia and North Carolina. Broiler breeder farms from three to five broiler company complexes in each state were visited on two separate occasions to document management practices and perform environmental sampling for Salmonella prevalence estimation. Salmonella was detected in 88% of the broiler breeder houses that were sampled and was identified on all 49 farms enrolled. Many management characteristics were consistent across the different states and companies. Multilevel analysis was used to evaluate management characteristics as risk factors for Salmonella prevalence and to estimate the proportion of variance residing at the different hierarchical sampling levels. Management characteristics associated with increased Salmonella prevalence included treatment of the flock for any disease, having dusty conditions in the house, having dry conditions under the slats and walking through the house more than one time per day to pick-up dead birds. After adjusting for state as a fixed effect, the percentages of variance in Salmonella prevalence occurring at the complex, farm, visit, house and individual sample levels were 5.2%, 6.8%, 11.8%, 2.8% and 73.4%, respectively. The intraclass correlations for samples collected from the same house; for samples from different houses during the same visit; for samples from different visits to the same farm; and for samples from different farms in the same complex were as follows: 0.27, 0.24, 0.12 and 0.05, respectively.     

Incidence of Clostridium perfringens in broiler chickens and their environment during production and processing.

During a calendar year, a study was conducted involving 16 broiler flocks on four different farms, two farms belonging to each of two major U.S. poultry integrators. As determined by the detection of Clostridium perfringens in fecal or cecal samples, 15 (94%) of the flocks became positive for this bacterial enteropathogen, and only one remained negative throughout the 6-to-8-wk rearing period. Paper pads beneath chicks that were transported from the hatchery to the rearing house were contaminated with C. perfringens in 15 (94%) of the flocks. When sampled biweekly through grow out, 13 of the flocks were C. perfringens positive at 2 wk of age. These results suggest that colonization of the intestinal tract of broilers by C. perfringens is an early event. Of the environmental samples, all but feed in the hopper were contaminated before placement for at least one of the rearing periods. All sample types were contaminated at some point during the 6-to-8-wk grow-out period. Of the on-farm environmental samples, the highest incidences (percentage positive) of C. perfringens were detected in wall swabs (53%), fan swabs (46%), fly strips (43%), dirt outside the house entrance (43%), and swabs of workers' boots (29%). Birds were usually transported to the processing plant in coops that were already contaminated with C. perfringens. In the plant, C. perfringens was isolated more frequently from samples of scald water than from those of chill water. Clostridium perfringens was recovered from broiler carcasses after chilling in 13 (81%) of the 16 flocks. The proportion of C. perfringens-positive carcasses for the contaminated flocks ranged from 8% to 68% with a mean of 30%.     

Epidemiologic features of Campylobacter jejuni isolated from poultry broiler houses and surrounding environments as determined by use of molecular strain typing

OBJECTIVE: To genetically type Campylobacter jejuni isolates from broiler houses or the external environment to identify the source of Campylobacter organisms in broiler chickens. SAMPLE POPULATION: Environmental samples associated with broiler chickens, in commercial grow-out houses. PROCEDURE: Polymerase chain reaction (PCR) was used to amplify flaB, and the amplicon was digested with Sau3A to create a restriction fragment length polymorphism assay; PCR was also used to detect a transcribed spacer region in the 23S rRNA gene. RESULTS: Isolates possessing a 23S spacer region were more prevalent outside broiler houses than inside. Houses that had previously contained chickens or lacked biosecurity procedures were more likely to contain isolates possessing the 23S spacer. One house contained only isolates possessing the spacer, whereas an adjacent house contained only isolates lacking the spacer. The flaB type detected in broiler houses was different from the type detected in the environment; however, many isolates within the broiler houses contained untypable flaB genotypes. CONCLUSIONS AND CLINICAL RELEVANCE: Most isolates from within houses were genetically distinct from isolates from outside houses that were examined by bacteriologic culture, suggesting an undetected source of C jejuni. Detection of isolates containing the 23S spacer appeared to be an indicator of environmental contamination of the houses. The observation of completely different C jejuni genetic types simultaneously within adjacent houses suggests that some types do not compete successfully during the grow-out period. In addition, the diversity of genotypes identified within broiler houses indicates the complexity of the ecologic features of C jejuni in the chicken environment.     

Campylobacter spp. in conventional broiler flocks in Northern Ireland: epidemiology and risk factors

Risk factors for Campylobacter infection in conventional broiler flocks in the time period up to the first removal of birds to slaughter were investigated over a maximum of five consecutive production cycles in a cohort of 88 broiler farms in Northern Ireland. Samples for Campylobacter culture, which consisted of 14 cloacal swabs per flock, were collected from one house on each farm prior to the first depopulation of birds. In total 388 flocks were sampled, of which 163 tested positive for Campylobacter spp. (42.0%; 95% CI 35.1–48.9%).

Data on farm and flock variables were obtained from questionnaires and random-effects logistic regression modelling used to investigate the association between these and the Campylobacter status of flocks. Six variables, all of which were significant at p < 0.05, were included in the final multivariable model. These included a combined variable on the presence of rodents on farms, which showed an increased odds of infection in flocks where the farmer reported having observed rodents during the production cycle (OR = 2.1) and/or where rodent droppings were observed at the sampling visit (OR = 2.9). Other variables that were significantly associated with an increased odds of infection included the age of the birds at sampling (odds ratio for its linear effect = 1.16 for each day of increase in age), season (summer versus other seasons OR = 2.0), farms with three or more broiler houses (OR = 2.9 compared to those with one house), the frequency of footbath disinfectant changes (OR = 2.5 for once weekly and OR = 4.0 for less than once weekly compared to twice weekly changes) and a categorical variable on the standard of tidiness and cleanliness of the broiler house ante-room (OR = 2.0 and OR = 4.9 for flocks from houses with poorer standards). There was no significant evidence of direct carry-over of infection from one production cycle to the next, neither was there evidence of other farm species acting as a source of infection.     

Carbon footprint of poultry production farms in South Georgia: A case study

A study was conducted in South Georgia to assess the carbon footprint of poultry farms. The study included broiler grow-out farms, pullet farms, and breeder farms from one commercial broiler complex. Data collection included the fuel and electricity bills from each farm, house size and age, flock size and number of flocks per year, and manure management. Emissions were calculated using a greenhouse gas (GHG) calculation tool. The carbon dioxide, nitrous oxide, and methane (CH₄) emissions were computed and a carbon footprint determined. Carbon footprint comparisons were made based on house construction and age. Based on these results, an evaluation of the mechanical sources of emissions showed that approximately 96% of the emissions from the broiler and pullet farms were from propane use, while only 3.9% of the total mechanical emissions from breeder farms were from propane use. On breeder farms, 83% of mechanical GHG emissions were the result of electricity use, while the pullet and broiler grow-out farms accounted for 2.9 and 2.7%, respectively, of the total mechanical emissions from electricity use. The data collected from the farms and entered into the GHG calculation tool revealed that breeder houses had higher levels of CH₄ emissions from manure management when compared to emissions from broiler and pullet houses. Even though the GHG emissions from poultry production farms were minimal compared to other animal production farms, the different sources of emissions were identified, thereby enabling the farmer to target specific areas for mitigation.     

Survey of parasites and bacterial pathogens from free-living waterfowl in zoological settings

To determine if free-living waterfowl residing in a zoological setting pose health risks for its animal collections, visitors, and employees, 450 fecal samples were collected and cultured for the presence of Campylobacter jejuni, Escherichia coli, Salmonella spp., and Pasteurella multocida. A survey of endoparasites infecting the waterfowl was also conducted. Sixty-seven percent, 42%, and 1.7% of the samples tested positive for E. coli, C. jejuni, and Salmonella spp., respectively. No P. multocida was isolated from the sampled population. Antimicrobial susceptibility testing for the bacterial isolates demonstrated that a majority of the isolates were susceptible to the antibiotics tested. A survey for parasites revealed 16% of the samples had coccidia oocytes; 8% of the sample had spirurid ova; and 17% of the sample had strongylate-type nematode ova. Ascaris spp. ova, Capillaria spp. ova, oxyurid ova, and mites were also noted in some fecal samples.     

Prevalence of Salmonella spp on conventional and organic dairy farms

OBJECTIVE: To describe the occurrence of fecal shedding, persistence of shedding over time, and serogroup classification of Salmonella spp on a large number of dairy farms of various sizes. DESIGN: Longitudinal study. SAMPLE POPULATION: 22,417 fecal samples from cattle and 4,570 samples from the farm environment on 110 organic and conventional dairy farms in Minnesota, Wisconsin, Michigan, and NewYork. PROCEDURE: 5 visits were made to each farm at 2-month intervals from August 2000 to October 2001. Fecal samples from healthy cows, calves, and other targeted cattle groups and samples from bulk tank milk, milk line filters, water, feed sources, and pen floors were collected at each visit. Bacterial culture was performed at 1 laboratory. RESULTS: Salmonella spp were isolated from 4.8% of fecal samples and 5.9% of environmental samples; 92.7% of farms had at least 1 Salmonella-positive sample. The 75th percentile for median within-herd prevalence of Salmonella spp in cattle for 5 sampling visits to a given farm was 2.0% and for maximum within-herd prevalence of Salmonella spp was 13.6%. Farms with a median within-herd prevalence of Salmonella spp of > or = 2.0% accounted for 76.3% of Salmonella-positive samples. There was no significant difference in the prevalence of Salmonella spp between conventional and organic farms. Seasonal differences in Salmonella shedding were observed. More farms had at least 1 serogroup B isolate than any other serogroup, whereas serogroup E1 was the most common among all Salmonella-positive samples. More than 1 serogroup was isolated on 76.4% of Salmonella-positive farms. CONCLUSIONS AND CLINICAL RELEVANCE: Salmonella spp were isolated from > 90% of dairy farms; however, 25% of farms accounted for > 75% of Salmonella-positive samples. This information is critical for the direction of intervention strategies to decrease the prevalence of Salmonella spp on dairy farms.     

Lighting during grow-out and Salmonella in broiler flocks

Background

Lighting is used during conventional broiler grow-out to modify bird behaviour to reach the goals of production and improve bird welfare. The protocols for lighting intensity vary. In a field study, we evaluated if the lighting practices impact the burden of Salmonella in broiler flocks.

Methods

Conventional grow-out flocks reared in the states of Alabama, Mississippi and Texas, USA in 2003 to 2006 were sampled 1 week before harvest (n = 58) and upon arrival for processing (n = 56) by collecting feathered carcass rinsate, crop and one cecum from each of 30 birds, and during processing by collecting rinsate of 30 carcasses at pre-chilling (n = 56) and post-chilling points (n = 54). Litter samples and drag swabs of litter were collected from the grow-out houses after bird harvest (n = 56). Lighting practices for these flocks were obtained with a questionnaire completed by the growers. Associations between the lighting practices and the burden of Salmonella in the flocks were tested while accounting for variation between the grow-out farms, their production complexes and companies.

Results

Longer relative duration of reduced lights during the grow-out period was associated with reduced detection of Salmonella on the exterior of birds 1 week before harvest and on the broiler carcasses at the post-chilling point of processing. In addition, starting reduced lights for ≥18 hours per day later in the grow-out period was associated with decreased detection of Salmonella on the exterior of broilers arriving for processing and in the post-harvest drag swabs of litter from the grow-out house.

Conclusions

The results of this field study show that lighting practices implemented during broiler rearing can impact the burden of Salmonella in the flock. The underlying mechanisms are likely to be interactive.     

Incidence of zoonoses in petting zoos and evaluation of hygiene measures to prevent the transmission to humans

In summer 2003, a study was performed in thirty Swiss petting zoos with the objective to determine the prevalence of zoonotic agents, and to describe hygiene measures implemented to reduce the risk of human infection. Fecal samples from different animal species were collected from the floor of pens to determine the prevalence of Salmonella spp., Campylobacter spp., verocytotoxin producing E. coli/ VTEC and Francisella tularensis. A questionnaire on hygiene measures, number of animals per species, housing system, care procedures and feeding was administered to every petting zoo to estimate exposure of visitors to zoonotic microorganisms. In total, 423 fecal samples were examined. Of these samples, 41 were positive for Campylobacter spp., which were mainly isolates from pigs and poultry (35% positive samples from each species). In pigs, 50% of the positive samples (6 samples) were typed as C. jejuni. The others were typed as C. coli (3) and C lan' (3), respectively. Five poultry isolates were typed as C. jejuni, and two as C. coli. Two samples were positive for Salmonella spp. Salmonella typhimurium was isolated from a goat, the other isolate could not be identified by serotyping. Neither Francisella tularensis nor verocytotoxin producing E. coli/ VTEC were found. The low prevalence of zoonotic microorganisms in Swiss petting zoos could be attributed to the cleanness of enclosures and animals, low stocking rates and good animal care. However, there is room for improvement concerning visitors' information on hygiene and hand washing. Furthermore, a strict separation between picnic - areas and animals should be enforced.     

Dynamics of populations of Campylobacter jejuni in two grandparent broiler breeder farms: persistent vs. transient strains

The objectives of the study were to characterize and investigate the populations of Campylobacter jejuni in two grandparent broiler breeder farms over four years. Caecal as well as farm environmental samples were obtained. Campylobacter isolates were characterized by macrorestriction profile (SmaI and KpnI-PFGE) and PCR-RFLP of the flaA gene. Susceptibility tests against seven antimicrobials were also performed. Birds were negative for Campylobacter spp. when they came to these two production farms (20 weeks), and most of the flocks remained uncolonized until they were 23 weeks old. Eighteen genotypes were characterized, with one of them (genotype 2) appearing and persisting over the study period in the two farms. In general, the strains exhibited high genetic stability, and most of them could be seen as transient in the farms, being substituted by other strains when their flock was substituted. Only one environmental sampling was positive for C. jejuni. Two different genotypes were characterized; one of them was isolated from the birds of that farm two years before. The susceptibility data point to the idea of an environmental source or reservoir of this genotype. Regarding the susceptibility of the populations, as other studies have shown, quinolone resistance (alone or combined with other resistances) was the most frequent: 68.5%. Quinolone- and multidrug-resistant strains are a matter of concern in public health. In conclusion, this survey shows the complexity of the study of the colonization of farms by C. jejuni.     

The role of litter beetles as potential reservoir for Salmonella enterica and thermophilic Campylobacter spp. between broiler flocks

We evaluated the role of beetles infesting broiler chicken rearing facilities as potential reservoirs for Salmonella enterica infections between successive broiler flocks. In addition, their role as potential reservoirs for thermophilic Campylobacter spp. was also investigated. Fourteen broiler houses located at 11 different farms were included in the study. The houses were nonrandomly selected on the basis of their salmonella status; nine were persistently contaminated with salmonella whereas five were salmonella negative. For each broiler house, two consecutive broiler flocks (i.e., 28 broiler flocks in all) as well as beetles collected during both rotations of production and in the empty period (after cleaning and disinfection) between these flocks were monitored for the presence of salmonella. Examinations for the presence of campylobacter in the same sample materials were also performed. Beetles sampled during production were positive for salmonella or campylobacter or both. Furthermore, in one house, the occurrence of Salmonella indiana in two consecutive broiler flocks coincided with the presence of S. indiana-contaminated beetles in the empty period between the flocks. The genotype of the identified S. indiana was in all cases identical when analyzed by pulsed-field gel electrophoresis. However, our results also suggest that salmonella from beetles may not always be transmitted to the chickens and that beetles living in contaminated houses can remain free of infection. All cases of campylobacter-positive beetle samples were detected in connection with a positive chicken flock; in no case was campylobacter isolated from beetles taken from the empty period between rotations. Four beetle species were identified during this study. Alphitobius diaperinus was found in all houses and was relatively abundant in most. Typhaea stercorea and Ahasverus advena were found in eight and nine houses, respectively, and were abundant in most of these. Carcinops pumilio was found in small numbers in eight houses. No other insect species was identified. These investigations have shown that beetles in broiler houses infrequently are positive for salmonella. However, transmission of S. indiana between two consecutive broiler flocks can coincide with the presence of salmonella-contaminated beetles in the empty period, indicating that the beetles were the reservoir of S. indiana between the two flocks. Concerning campylobacter, the results suggest that beetles do not play a significant role as a reservoir of campylobacter from one rotation to the next.     

Serum agglutinin titers against somatic and flagellar antigens of Campylobacter jejuni and isolation of Campylobacter spp in chickens

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.     

Risk factors for Salmonella persistence after cleansing and disinfection in French broiler-chicken houses

A prospective survey was carried out in 86 broiler houses in western France to identify risk factors for Salmonella persistence in French broiler houses. The Salmonella status of the house after cleansing and disinfection, was assessed from gauze-swab samples taken from the walls, feeders, ventilation system and bedding (analysed with classical bacteriological methods). Thirty three (38%) houses had at least one contaminated sample and were classified as Salmonella-contaminated houses in the logistic regression. The absence of a terminal disinfection and a disinfection procedure performed by the farm staff rather than a contractor were positively related to the Salmonella contamination of the house after cleansing and disinfection. The risk for Salmonella persistence after decontamination was increased if rodents were observed by the farmer, if a large part of the access area to the house was accessible to trucks, and if a disease leading to a treatment occurred in the previous flock.     

An epidemiological study of selected calf pathogens on Holstein dairy farms in southwestern Ontario.

Fecal samples from calves on 78 randomly selected Holstein dairy farms in southwestern Ontario were screened for Salmonella, Campylobacter jejuni/coli, enteropathogenic Escherichia coli, rotavirus and coronavirus. Based on the observed prevalence, 22% of farms had calves infected with Salmonella, 13% with Campylobacter jejuni/coli, 41% with enteropathogenic E. coli, 19% with rotavirus and 5% with coronavirus. These estimates can be modified, using a method developed by Mullen and Prost (1983) for the World Health Organization, to account for the nature of the laboratory test used. If the test is assumed to have no false positives (that is, if an organism is detected it must be there), then the observed prevalence estimates seen on this study may greatly underestimate the true prevalence of infected premises. The use of nipple feeders for calves was associated with an increased probability of farms having calves shedding detectable fecal levels of Salmonella, E. coli, or one of the two viruses. The use of group pens was associated with an increased odds of finding C. jejuni. Calves with diarrhea on these farms tended to have increased odds of shedding rotavirus, and E. coli with the K99 antigen. However, at the farm level, none of the organisms was associated with above median levels of morbidity. Farms positive for one or other of the viruses had increased odds of experiencing calf mortality relative to virus-negative farms, and farms positive for C. jejuni/coli had decreased odds of mortality.(ABSTRACT TRUNCATED AT 250 WORDS)     

The occurrence of Cryptosporidium parvum, Campylobacter and Salmonella in newborn dairy calves in the Manawatu region of New Zealand

AIM: To determine the occurrence of Cryptosporidium parvum oocysts, Campylobacter spp and Salmonella spp in faecal samples taken from newborn dairy calves on 24 dairy farms in the Manawatu region of New Zealand. METHODS: A cross-sectional study was conducted during the 2002 calving season. Faecal samples were collected from 185 newborn calves from a convenience sample of 24 dairy farms. The samples were tested microscopically for the presence of C. parvum oocysts, and bacteriologically for the presence of Campylobacter spp and Salmonella spp. RESULTS: Infections with C. parvum were identified in 33/156 (21.2%) calves from 10 farms. More than 10(6) oocysts/g (OPG) faeces were detected in calves from four farms. Campylobacter spp were isolated from 58/161 (36%) calves from 18 farms; in particular, C. jejuni subsp jejuni was isolated from 11/161 (6.8%) calves from seven farms. Salmonellae were not detected. CONCLUSIONS: Despite the short and concentrated calving pattern and the long interval between calving seasons characterising most dairy farms in New Zealand, C. parvum is widespread among calves. Campylobacter spp, especially C. jejuni, rapidly colonise the intestinal tract of newborn calves. RELEVANCE: This study provided an estimate of the ecological impact of newborn dairy calves with regard to the potentially zoonotic enteric pathogens most frequently isolated from human gastrointestinal infections in New Zealand.     

Prevalence of subclinical coccidiosis in broiler farms in Turkey

The presence of Eimeria spp. oocysts in fecal samples collected from 1,108 broiler houses in six regions, representing about 12% of all broiler farms in Turkey, was studied using the modified McMaster method. The age of the chickens in the 1,108 pens varied from 1 to 50 days. Oocysts were found in 602 (54.3%) of these broiler houses, and the mean OPG (oocysts per gram of feces) in those samples was 36,498.7 (50–952,000). No indication of clinical coccidiosis or other clinically evident infection or wide mortality was encountered in any of the pens studied. Further study showed that the age of the chickens, the occurrence of diarrhea on the houses and the density of broiler breeding in the area correlated with subclinical coccidiosis prevalence.     

Effects of marketing stress on fecal excretion of Salmonella spp in feeder calves

Fecal samples were collected from 200 feeder-calves on farms in Tennessee, after assembly at a Tennessee auction market, and after transport to a Texas feedyard. A final fecal sample was collected from each calf after 30 days of feedyard confinement. The fecal samples were cultured for the presence of Salmonella spp. Salmonella isolates were serotyped and antimicrobial drug-resistance patterns determined. The number of calves fecal culture-positive for Salmonella spp increased from 0 on the Tennessee farms and auction market to 3/200 (1.5%) at entry into the Texas feedyard, and 16/200 (8%) after 30 days of feedyard confinement. Salmonella serotypes isolated and the number of isolates of each serotype were S reading (8), S cerro (4), S newbrunswick (3), S anatum (2), and S typhimurium (copenhagen; 2). All Salmonella isolates were resistant to 5 or more of 13 antimicrobial drugs tested. Salmonella reading isolates were resistant to 10 or 11 of 13 antimicrobial drugs. The results indicated that the calves could have been infected with Salmonella spp prior to or during the course of the study, and that marketing stress as they moved from farm through feedyard may have induced fecal excretion of salmonellae. In addition, the pattern of antimicrobial drug resistance in the Salmonella isolates was broad.     

Distribution of Salmonella serovars and phage types on 80 Ontario swine farms in 2004

The objective of this study was to describe the distribution of Salmonella spp. on Ontario grower-finisher pig farms. Eighty swine farms were visited from January through July 2004. On each farm, fecal samples were collected from 5 pens, 2 rectal samples and 1 pooled sample from fresh manure on the floor per pen. Salmonella was isolated from 91 (11%) of the 800 rectal samples and 73 (18%) of the 397 pooled samples. Overall, Salmonella was recovered from 37 (46%) of the 80 farms. On each positive farm, Salmonella was cultured from 1 to 7 pigs or 1 to 5 pens. Of the 37 farms, 18, 13, 5, and 1 yielded 1, 2, 3, and 4 serovars, respectively. The most common serovars were S. Typhimurium var. Copenhagen, S. Infantis, S. Typhimurium, S. Derby, S. Agona, S. Havana, and S. enterica subsp. I:Rough-O. The 3 most frequent phage types were PT 104, PT 104a, and PT 104b. There was a statistically fair agreement between samples collected directly from pigs and pooled pen samples in determining the Salmonella status at the pen and farm level (kappa = 0.6, P < 0.0001). However, in 62 pens, Salmonella status, serovars, or phage types differed between the pig and pooled pen samples. The distribution of Salmonella on the swine farms in this study indicates that, in developing an intervention strategy, priority should be given to farms positive for S. Typhimurium var. Copenhagen. Also, the variation in Salmonella status between pig and pooled pen samples deserves consideration in a sampling strategy.     

Prevalence and risk factors for Campylobacter spp. in chicken broiler flocks in Reunion Island (Indian Ocean)

Our objectives were to determine Campylobacter prevalence in broiler chicken flocks in Reunion Island and to define specific practices associated with the presence of Campylobacter spp. Infection in Reunionese broiler flocks. Fifty broiler flocks were studied in Reunion Island from May 2007 to February 2009. A questionnaire was submitted to the farmers and samples of fresh droppings were collected to assess the flock's Campylobacter status. Fifty four percent of the flocks were infected by Campylobacter spp.: 30% (95% CI: 28.71-31.29) were infected with Campylobacter coli and 17% (95% CI: 15.95-18.05) with Campylobacter jejuni; only 7% (95% CI: 6.28-7.72) were infected by both species at the same time. Several poultry houses in the farm (OR=11.2; [1.05-92]) and cleaning without any detergent (OR=13.1; [2.1-78.3]) increased the risk of Campylobacter infection. A distance higher than 500 m between broiler farms (OR=0.27; [0.1-0.8]) and use of disinfectant during the rearing period decreased this risk of infection (OR=0.15; [0.1-0.75]).