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1.
We investigated the associations between Campylobacter colonisation and management practices and farm characteristics in 603 housed broiler batches originating from 137 farms in Great Britain. All study batches were the initial batch slaughtered from the selected house on enrolled farms. Between 1 and 15 batches were sampled from each farm throughout the study. A total of 34.2% of the batches was Campylobacter positive and multivariable multilevel logistic regression revealed that the risk of Campylobacter colonisation was highest in July (OR = 3.4, CI95%:1.8; 6.4), August (OR = 3.4, CI95%:1.9; 6.2) and September (OR = 3.7, CI95%:1.9; 7.1). Cattle on or adjacent to the farm increased the risk (OR = 1.7, CI95%:1.1; 2.7), whereas chlorinated drinking water reduced it (OR = 0.5, CI95%:0.2; 0.9). If the first removed batch from the previous flock in the house had been Campylobacter positive, the first batch of the following flock was also more likely to be colonised (OR = 3.2, CI95%:2.1; 4.9). This association was more likely due to a persistent risk practice or source of Campylobacter on the farm than a direct carry-over from previous flock.  相似文献   

2.
Consumption of raw or undercooked poultry products contaminated with Campylobacter has been identified as a risk factor for human campylobacteriosis. We determined whether slaughtering of Campylobacter‐positive flocks was associated with contamination of chicken products derived from Campylobacter‐negative flocks slaughtered at the same abattoir. The presence of Campylobacter was investigated in 22 broiler farms 1 week prior to slaughter and in one abattoir on nine separate slaughter days. A total of 600 bulk packed chicken products were tested, with 198 (33.0%) of the products found to be Campylobacter positive. Of the 350 chicken products originating from Campylobacter‐positive flocks, 180 (51.1%) were contaminated with the bacteria. In contrast, only 18 (7.2%) of 250 chicken products derived from Campylobacter‐negative flocks were contaminated. In 14 of these 18 products, the Campylobacter isolates were identical to isolates obtained from the flock slaughtered immediately prior to the Campylobacter‐negative flock. Notably, on 4/6 slaughter days, Campylobacter‐negative flocks were slaughtered prior to the positive flocks, and Campylobacter was absent from all chicken products originating from the negative flocks. These results suggest that implementation of logistic slaughter (where Campylobacter‐negative flocks are slaughter first) significantly decreases the prevalence of Campylobacter‐positive chicken products.  相似文献   

3.
Campylobacter spp. are important causes of bacterial zoonosis, most often transmitted by contaminated poultry meat. From an epidemiological and risk assessment perspective, further knowledge should be obtained on Campylobacter prevalence and genotype distribution in primary production. Consequently, 15 Austrian broiler flocks were surveyed in summer for their thermophilic Campylobacter spp. contamination status. Chicken droppings, dust and drinking water samples were collected from each flock at three separate sampling periods. Isolates were confirmed by PCR and subtyped. We also compared three alternative methods (culture‐based enrichment in Bolton broth, culture‐independent real‐time PCR and a lateral‐flow test) for their applicability in chicken droppings. Twelve flocks were found to be positive for thermophilic Campylobacter spp. during the entire sampling period. Seven flocks (46.6%) were contaminated with both, C. jejuni and C. coli, five flocks harboured solely one species. We observed to a majority flock‐specific C. jejuni and C. coli genotypes, which dominated the respective flock. Flocks within a distance <2 km shared the same C. jejuni genotypes indicating a cross‐contamination event via the environment or personnel vectors. Multilocus sequence typing (MLST) of C. jejuni revealed that the majority of isolates were assigned to globally distributed clonal complexes or had a strong link to the human interface (CC ST‐446 and ST4373). The combination of techniques poses an advantage over risk assessment studies based on cultures alone, as, in the case of Campylobacter, occurrence of a high variety of genotypes might be present among a broiler flock. We suggest applying the lateral‐flow test under field conditions to identify ‘high‐shedding’ broiler flocks at the farm level. Consequently, poultry farmers and veterinarians could improve hygiene measurements and direct sanitation activities, especially during the thinning period. Ultimately, real‐time PCR could be applied to quantify Campylobacter spp. directly from chicken droppings and avoid non‐interpretable results achieved by culture‐dependent methods.  相似文献   

4.
Broiler chicken flocks are a significant source of Campylobacter jejuni and Campylobacter coli that result in the major public health problem of campylobacteriosis. Accurate estimates of the prevalence of both C. coli and C. jejuni in flocks would enhance epidemiological understanding, risk assessment and control options. This study combined results from a panel of 10 detection tests (direct culture, enrichment and PCR) on caecal samples from flocks at slaughter. A parallel interpretation approach was used to determine the presence of Campylobacter spp. and for C. jejuni and C. coli individually. The sample was considered positive if at least one method detected the target and this interpretation was taken to represent a ‘proxy gold standard’ for detection in the absence of a gold standard reference test. The sensitivity of each individual method to detect Campylobacter spp., C. jejuni and C. coli was then estimated relative to the proxy gold standard. Enrichment in adapted Exeter broth (deficient in polymyxin B) with a resuscitation step was 100% sensitive, whilst direct culture on modified charcoal cefoperazone deoxycholate agar (mCCDA) was highly sensitive (97.9%). Enrichment methods using Preston broth and Bolton broth were significantly less sensitive. Enrichment in Exeter broth promoted the recovery of C. jejuni, whilst enrichment in Bolton broth favoured C. coli. A RT‐PCR detection test could identify 80% of flocks that were co‐colonised with both species. This study found that 76.3% (n = 127) of flocks were colonised with Campylobacter spp. The majority (95.9%) of Campylobacter‐positive flocks were colonised with C. jejuni; however, approximately one‐third of positive flocks were simultaneously colonised with both C. jejuni and C. coli. The findings highlight the impact of different detection methodologies on the accuracy of the estimated incidence of both C. jejuni and C. coli entering the abattoir within broiler flocks and the associated public health risks.  相似文献   

5.
1. This study investigated the potential of a commercially available acidified water treatment (PWT) for reducing the number of Campylobacter in vitro and other bacteria in the gut of live broilers.

2. In vitro tests indicated that PWT was highly effective for reducing Campylobacter jejuni and Campylobacter coli at the recommended concentration in water, reducing populations by greater than 7 log10 CFU/ml after 24 h exposure. The decrease in the number of Salmonella serovar Enteritidis and Escherichia coli was not significant.

3. Addition of PWT to the broiler drinking water for the first 7 d, 2 d before and 2 d after each feed change and at feed withdrawal prior to slaughter or only after feed withdrawal had no effect on the number of Campylobacter in caecal samples on farm before thinning and depopulation compared to untreated controls.

4. Although PWT was effective for reducing Campylobacter in water, the results suggest that it does not reduce the number of Campylobacter in the caeca of broilers prior to slaughter under the conditions used in the study.  相似文献   


6.
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; CI95%: 3.25–8.52) in decoys and 2.3% (9/387; CI95%: 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; CI95%: 2.3–4.3) and 4.6% (18/394; CI95%: 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.  相似文献   

7.
A cross-sectional study was performed to assess the occurrence of Campylobacter species and to identify potential associated risk factors for wild artiodactyl species in southern Spain. Campylobacter species were isolated in 55 of 363 (15.2%) faecal samples. Campylobacter was identified in faeces from wild boar (49/126; 38.9%), red deer (5/179; 2.8%) and mouflon (1/13; 7.7%) but not from fallow deer (0/45). The isolated Campylobacter species were identified as C. jejuni (2 isolates; 3.6%), C. coli (11 isolates; 20.0%) and C. lanienae (37 isolates; 67.3%). Five isolates (9.1%) could not be identified at the species level. This report is the first to describe C. lanienae infection in wild ruminant species. Resistance to erythromycin (4.8%), ciprofloxacin (37.5%), tetracycline (52.9%) and streptomycin (55%) were detected. C. lanienae presented a significantly higher number of susceptible isolates to ciprofloxacin and tetracycline than C. coli. Due to the low number of positive wild ruminants, a Generalised Estimating Equations model was only carried out for wild boar. The model indicated that the risk factors associated with Campylobacter infection were the density of wild boar (>10/100 ha) (OR: 3.05; CI95%: 2.2–4.3), the presence of artificial waterholes (OR: 3.67; CI95%: 1.3–10.5) and the winter season (OR: 3.30; CI95%: 1.9–5.8). Campylobacter infection is widespread in wild boar populations in southern Spain. These findings suggest that wild artiodactyls, particularly wild boar, constitute a reservoir of Campylobacter species, including resistant and multi-resistant strains, which may be of public health concern.  相似文献   

8.
Campylobacter is the second leading cause of foodborne illness in the United States. Although many food production animals carry Campylobacter as commensal bacteria, consumption of poultry is the main source of human infection. Previous research suggests that the biology of Campylobacter results in complete flock colonization within days. However, a recent systematic review found that the on-farm prevalence of Campylobacter varies widely, with some flocks reporting low prevalence. We hypothesized that the low prevalence of Campylobacter in some flocks may be driven by a delayed introduction of the pathogen. The objectives of this study were to (a) develop a deterministic compartmental model that represents the biology of Campylobacter, (b) identify the parameter values that best represent the natural history of the pathogen in poultry flocks and (c) examine the possibility that a delayed introduction of the pathogen is sufficient to replicate the observed low prevalence examples documented in the literature. A deterministic compartmental model was developed to examine the dynamics of Campylobacter in chicken flocks over a 56-day time period prior to movement to the abattoir. The model outcome of interest was the final population prevalence of Campylobacter at day 56. The resulting model that incorporated a high transmission rate (β = 1.04) was able to reproduce the wide range of prevalence estimates observed in the literature when pathogen introduction time is varied. Overall, we established that the on-farm transmission rate of Campylobacter in chickens is likely high and can result in complete colonization of a flock when introduced early. However, delaying the time at which the pathogen enters the flock can reduce the prevalence observed at 56 days. These results highlight the importance of enforcing strict biosecurity measures to prevent or delay the introduction of the bacteria to a flock.  相似文献   

9.
Summary The objective of the study was to evaluate the performance of different combinations of sample type, transport medium and culture methods for the recovery of Campylobacter jejuni and C. coli from broiler flocks at primary production. Boot swabs moistened with one of four different transport media [maximum recovery diluent (n = 120), Exeter broth (EX) (n = 120), buffered peptone water (n = 120) and modified semi‐solid Cary‐Blair (n = 120)], caecal samples (n = 40) and faecal samples (n = 120) from 40 broiler flocks were compared and sensitivity estimates obtained using a Bayesian model. Samples were cultured onto mCCDA before and after enrichment in EX and incubated microaerobically at 41.5°C. Campylobacter suspect colonies were identified to the species level by multiplex PCR. Results from the Bayesian model indicated that boot swabs after enrichment had higher sensitivity (90–94%) than caecal contents before or after enrichment (84% and 89%, respectively) and faecal samples after enrichment (82%) for the detection of Campylobacter spp., although these differences were not statistically significant. Enrichment significantly increased the sensitivity of boot swab and caecal samples for detection of Campylobacter spp. and C. jejuni, respectively. However, the enrichment of caecal samples resulted in a significant decrease in the sensitivity of these samples for detection of C. coli. There was much greater variation in the sensitivity estimates of the methods for detecting C. coli than for C. jejuni, and the ranking of methods was different between the two species. Boot swabs gave the best sensitivity values for detection of C. jejuni, and enrichment culture of faecal samples was the most sensitive method for detection of C. coli.  相似文献   

10.
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.  相似文献   

11.
The study aimed to investigate the effect of feed supplements, viz Lactobacillus plantarum LGFCP4 (laboratory isolate from GIT of Guinea fowl), Lactobacillus acidophilus (NCDC, Karnal) and in‐feed antibiotic bacitracin methylene disalicylate (BMD) on growth performance, FCR, carcass traits and immune organs weight, intestinal histomorphometry and gastrointestinal microflora population in broiler chickens. In a completely randomized design, CARIBRO‐Dhanraja broiler chicks (n = 160) were used with four treatment groups. During the entire experimental duration of 35 days, treatment groups were provided with different dietary treatments (T1 – basal diet (negative control), T2 – antibiotic growth promoter BMD 20 g/100 kg feed (positive control), T3 – 1 × 108 cfu of L. acidophilus/gm‐fermented feed +MOS 1 g/kg feed and T4 – 1 × 108 cfu of laboratory‐isolated L. plantarum LGFCP4/gm‐fermented feed+ MOS 1 g/kg feed. After 35 days of experimental period, no significant results have been observed in different growth performance traits among treatment groups. Cut‐up parts and edible organs' weight remained unaffected by dietary supplementation, whereas weight of immune organs were significantly higher (p < 0.05) in L. plantarum LGFCP4‐supplemented group. At the end of feeding trial, significantly (p < 0.05) lower E. coli count was observed in crop of T4 birds, while in ileum, T2 and T3 showed lower count. In caeca, T2 group showed lowest E. coli count. Salmonella count in crop and ileum was significantly (p < 0.05) low in T3 and T4, while in caeca, T2 group showed lowest count. In terms of histomorphometry, duodenal villous height (VH), crypt depth (CD) and VH:CD ratio were higher for T3 and T4 and lowest values were obtained for T2 group. The results of the study showed that L. plantarum LGFCP4 isolated from GIT of guinea fowl can effectively replace in‐feed antibiotic growth promoters in broiler diets by altering intestinal villi morphology and improving the gut health by reducing the pathogenic microbial load.  相似文献   

12.
The resistance patterns of Campylobacter spp. isolated from retail broiler chicken meat originating either from Estonia, Lithuania or Latvia collected in Estonia were determined. Additionally, in collaboration with the laboratories of several Estonian hospitals, antimicrobial susceptibility patterns were determined for Campylobacter isolates from patients with severe Campylobacter enteric infections. The isolates were identified at the species level by the PCR method. Respectively, 88.8% of the isolates were C. jejuni, and 11.2% were C. coli. In total, 126 Campylobacter isolates of broiler chicken meat and human origin were tested for minimal inhibitory concentrations (MICs) with the broth microdilution VetMICTH method (National Veterinary Institute; Uppsala, Sweden) for a total of six antimicrobials. Resistance to one or more antimicrobials was detected in 62 (63.3%) of Campylobacter broiler chicken meat isolates and in 20 (71.4%) of human‐origin isolates. Large proportions of the broiler chicken meat isolates were resistant to ciprofloxacin (60.2%). Multidrug resistance (i.e. to three or more unrelated antimicrobials) was detected in five (5.1%) C. jejuni isolates. Among the human isolates, 20 (71.4%) were resistant to fluoroquinolones, and two (7.1%) C. jejuni isolates exhibited multidrug resistance. The chicken meat isolates of Estonian origin were the most susceptible. However, a high proportion of fluoroquinolone‐resistant C. jejuni isolates were found in Latvian and Lithuanian products. The results of this study indicate that the problems caused by the inappropriate use of antimicrobials extend beyond the country in which a food originates; therefore, both domestic and international interventions and agreements are required to implement common policies on antimicrobial usage and to minimize the emergence of Campylobacter drug resistance.  相似文献   

13.
Broiler meat is regarded as the most common source of Campylobacter infection and risk management measures are required to reduce broiler meat contamination. Among the quantitative risk assessments for Campylobacter in broiler meat, evaluation of the poultry processing stage is particularly important for predicting the contamination level of broiler meat and the effects of control measures. In this study, we built a simulation model for cross‐contamination during poultry processing focusing on Campylobacter contamination at the individual carcass level. Using this model, we examined changes in the prevalence of contaminated carcasses and the number of Campylobacter per carcass after processing. As a result, it was found that the prevalence and number of Campylobacter after processing were largely influenced by the number of Campylobacter on the contaminated carcasses before processing. In the baseline model, where it was assumed that the mean number of Campylobacter on contaminated carcasses before processing was 4.7 log10 cfu per carcass, the prevalence after processing was less than that before processing. Although the median value of Campylobacter on contaminated carcasses was reduced after processing, the distributions after processing became wider and the upper limit of the 95% credible interval of Campylobacter on contaminated carcasses remained elevated. The individual‐based simulation model can trace individual level changes considering discrete interactions, while models tracing mean values cannot handle these interactions in detail. The individual‐based approach is considered useful for modelling cross‐contamination among individual carcasses during poultry processing.  相似文献   

14.
ABSTRACT

1. Chicken-associated Campylobacter spp. are the cause of most food poisoning cases in Europe. In order to study the host–pathogen interactions, a reliable and reproducible method of colonising chickens with the bacteria is required.

2. This study aimed to identify a more appropriate and less invasive method of colonisation (cf. gavaging) by seeding bedding material (litter) that commercial chickens are kept on with a mixture of Campylobacter spp., broth and faeces.

3. The first phase of the study tested the longevity of Campylobacter spp. recovery in seeded litter over 24 h: significantly more Campylobacter spp. was recovered at 0 or 3 h post-seeding than at 6 and 24 h post-seeding, indicating that the pathogen can survive to detectable levels for at least 3 h in this environment.

4. In the second phase, three groups of 10 broiler chickens (negative for Campylobacter spp. prior to exposure) were exposed at 21 days of age to one of three different Campylobacter jejuni and C. coli mixes (A, B, C), using the method above. At 28 days of age, birds were euthanised by overdose of barbiturate or cervical dislocation, and livers and caeca removed for Campylobacter spp. assessment.

5. All liver and 28/30 caeca samples tested positive for Campylobacter spp., with mix A and C giving higher counts in the caeca than mix B. The method of euthanasia did not affect Campylobacter spp. counts.

6. In conclusion, a successful method for reliably colonising broiler chickens with Campylobacter spp. has been developed which negates the need for gavaging and is more representative of how contamination occurs in the field.  相似文献   

15.
Campylobacter was isolated from 67 (47.2%) of 142 broiler flocks between September 2009 and February 2010. The prevalence of Campylobacter in broiler flocks was significantly lower during January and February than it was from September to December. Campylobacter colonization was more common in flocks that were not provided with a disinfected water supply, which was consistent with the findings of a previous study. The prevalence of antimicrobial drug‐resistant Campylobacter spp. was investigated, and the minimum inhibitory concentrations of eight antimicrobial agents were determined for 122 Campylobacter jejuni isolates and 46 Campylobacter coli isolates from broiler flocks between 2007 and 2010. In this study, 29.5% (36/122) of C. jejuni isolates and 41.3% (19/46) of C. coli isolates were resistant to enrofloxacin (ERFX), whereas all isolates were susceptible to erythromycin. Furthermore, the ERFX‐resistant isolates were tested for susceptibility to other classes of antimicrobial agents, and 55.6% (20/36) of ERFX‐resistant C. jejuni isolates and 47.4% (9/19) of ERFX‐resistant C. coli isolates were resistant to at least one of aminobenzyl penicillin, dihydrostreptomycin and oxytetracycline. To avoid an impact of antimicrobial drug‐resistant Campylobacter spp. on the efficacy of antimicrobial treatment for human campylobacteriosis, prudent use of antimicrobial agents is a requisite. The use of antimicrobial agents should be accompanied by various approaches such as prevention of Campylobacter colonization in broiler flocks with the aim of lowering the occurrence of Campylobacter infection in humans.  相似文献   

16.
To explore the in vivo antimicrobial activity of cefquinome against Pasteurella multocida in piglets, a piglet tissue cage infection model was used in this study. After the population of P. multocida reached 107 CFU/mL in a tissue cage, piglets received an intramuscular administration of cefquinome at 0.2, 0.4, 0.8, 1, 2, and 4 mg/kg once daily for 3 days. To assess the tissue cage pharmacokinetics (PKTCF) of cefquinome, tissue cage fluid was collected for cefquinome analysis at 1, 3, 6, 9, 12, and 24 hr after each of the 3 daily drug administrations. Bacteria were counted every 24 hr after drug administration and at 48 and 72 hr after the last administration. Evaluation of the relationship between pharmacokinetic/pharmacodynamic (PK/PD) parameters and the antibacterial effect showed that the surrogate of %T > minimum inhibitory concentration (MIC) (R2 = 0.981) was the best PK/PD index that correlated with effectiveness of cefquinome against P. multocida. The respective values of %T > MIC required for continuous 1/3‐log, 1/2‐log, and 1‐log reductions were 14.23, 34.45, and 73.44%, respectively, during each 24‐hr treatment period. In conclusion, cefquinome exhibited a potent antibacterial effect against P. multocida. When %T > MIC reached 73.44%, cefquinome exhibited a bactericidal effect against P. multocida after three successive daily administrations.  相似文献   

17.
This study aims to investigate the genetic diversity of thermotolerant Campylobacter in commercial broiler flocks and in the environment of broiler farms in Belgium. Seven out of 18 investigated flocks became colonized during rearing. Fluorescent amplified fragment length polymorphism (FAFLP), pulsed field gel electrophoresis (PFGE), restriction fragment length polymorphism of the flagellin A gene (flaA-RFLP) and antimicrobial resistance profile (ARP) were used for typing of the isolates. By the combination of FAFLP and PFGE, 22 Campylobacter genotypes could be distinguished. Colonization was almost exclusively with Campylobacter jejuni and unique genotypes were found in each flock. Multiple genotypes were detected in the broilers of 3 flocks, either simultaneously or successively. In 5 flocks, strains that were resistant to at least one antibiotic (mostly tetracycline) were found. The presence of other broiler houses on the farm did not result in a higher probability of colonization. The nipple water was contaminated with the same genotype as the broilers, illustrating its importance for transmission of Campylobacter. The same genotype was detected in a water puddle and in the broiler flock during rearing in 3 flocks. Once, the same genotype was isolated from the ditch water shortly before it was detected in the broilers.  相似文献   

18.
ABSTRACT

1. In this study, classical and molecular microbiological methods for detection and quantification of Campylobacter spp. were used to estimate their prevalence in faecal samples and skin swabs collected from 31 broiler flocks (20 farms) in Portugal, and measure the impact of transport-related factors on the expected rising excretion rates from the farm to the slaughterhouse.

2. Data on husbandry practices and transport conditions were gathered, including time in transit, distance travelled or ante-mortem plant-holding time.

3. A generalised linear mixed model was used to evaluate the significance of a potential post-transport rise in Campylobacter spp. counts and to assess risk determinants.

4. At least one flock tested positive for Campylobacter spp. in 80% of the sampled farms. At the slaughterhouse, Campylobacter spp. were detected in all faecal samples, C. jejuni being the most commonly isolated.

5. A post-transport rise of Campylobacter spp. counts from skin swabs was observed using classical microbiological methods (from a mean of 1.43 to 2.40 log10 CFU/cm2) and molecular techniques (from a mean of 2.64 to 3.31 log10 genome copies/cm2).

6. None of the husbandry practices or transport-related factors were found to be associated with Campylobacter spp. counts.

7. This study highlights the need for more research to better understand the multi-factorial nature of Campylobacter spp., a public health threat that was found to be highly prevalent in a sample of Portuguese poultry farms.  相似文献   

19.
Broiler-chicken are often Salmonella carriers. However, these bacteria are responsible for major food-borne human infection, in which poultry-meat products are frequently implicated. In order to prevent Salmonella spread during the slaughtering process, control measures should be implemented at the farm level to reduce the prevalence before slaughtering. The objective of this study was to identify the risk factors for Salmonella contamination in French commercial broiler flocks at the end of the rearing period. A prospective study was carried out in 1996 and 1997 on 86 broiler flocks located in western France. The Salmonella status of the flocks was assessed by means of litter swabs and dust samples analyzed with classical bacteriological methods. Sixty flocks (70%) had at least one contaminated environmental sample and were classified as Salmonella-contaminated flocks. Logistic regression was used to assess association of managerial practices, general hygiene and results of environmental Salmonella recovery, with the odds that the flock itself would be Salmonella-contaminated at the end of the rearing period. Salmonella contamination of the house before placing day-old chicks and the Salmonella contamination of day-old chicks were significantly related to Salmonella contamination of the flock at the end of the rearing period. The risk for Salmonella contamination of the flock was increased when feed trucks parked near the entrance of the change room and when feed meal, instead of small pellets, was provided at the start.  相似文献   

20.
The present study assessed the efficacy of vaccination against genotype 1 porcine reproductive and respiratory syndrome virus (PRRSV) in terms of reduction of the transmission. Ninety-eight 3-week-old piglets were divided in two groups: V (n = 40) and NV (n = 58) that were housed separately. V animals were vaccinated with a commercial genotype 1 PRRSV vaccine while NV were kept as controls. On day 35 post-vaccination, 14 NV pigs were separated and inoculated intranasally with 2 ml of a heterologous genotype 1 PRRSV isolate (“seeder” pigs, SP). The other V and NV animals were distributed in groups of 5 pigs each. Two days later, one SP was introduced into each pen to expose V and NV to PRRSV. Sentinel pigs were allocated in adjacent pens. Follow-up was of 21 days. All NV (30/30) became viremic after contact with SP while only 53% of V pigs were detected so (21/40, p < 0.05). Vaccination shortened viremia (12.2 ± 4 versus 3.7 ± 3.4 days in NV and V pigs, respectively, p < 0.01). The 50% survival time for becoming infected (Kaplan–Meier) for V was 21 days (CI95% = 14.1–27.9) compared to 7 days (CI95% = 5.2–8.7) for NV animals (p < 0.01). These differences were reflected in the R value as well: 2.78 (CI95% = 2.13–3.43) for NV and 0.53 (CI95% = 0.19–0.76) for V pigs (p < 0.05). All sentinel pigs (10/10) in pens adjacent to NV + SP pens got infected compared to 1/4 sentinel pigs allocated contiguous to a V + SP pen. These data show that vaccination of piglets significantly decrease parameters related to PRRSV transmission.  相似文献   

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