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1.
A total of 412 feed samples and 632 litter samples from 15 poultry farms (2 breeding farms and 13 rearing farms) were examined for salmonella. Twelve of these farms had salmonella in litter, five farms had salmonella in the feed and four had salmonella in both feed and litter. Seventeen feed samples (4.13%) and 121 litter samples (19.15%) were contaminated with salmonella. Sixteen salmonella serotypes were encountered, of which six were found in both feed and litter. Salmonella concord and S. livingstone were present in the litter of one breeding farm and its progeny farms. The five most frequently isolated salmonella serotypes in feed and litter were S. concord (17.39%), S. coeln (15.94%), S. livingstone (15.22%), S. manhattan (11.59%), and S. paratyphi B var. java (8.69%). The pathogenicities of those serotypes were determined by calculating their median lethal doses (LD50) 24 and 48 hr postinjection of 1,050 one-day-old broiler chicks via the navel into the yolk sac. The composite 48-hr LD50s (viable cells) were: S. concord, less than 8.8 X 10(3); S. livingstone, 1.1 X 10(5); S. manhattan, 3.5 X 10(5); S. coeln, 1.25 X 10(7); and S. paratyphi B var. java, 1.73 X 10(7).  相似文献   

2.
From 10 egg production poultry farms 1516 samples were collected and examined for the presence of salmonella. The samples were: 201 chicken, 36 sparrows, 35 rats, 35 pools of 20 flies each, 450 eggs, 60 mattresses, 188 feces, 425 feedstuffs and 86 water samples. Salmonellae were isolated only from 163 (10.8%) samples. From the 146 (89.6%) of these S. gallinarum was isolated. From the rest 17 (10.4%) the following mobile salmonella strains were isolated: two strains of S. virchow and Salmonella of subgroup II, four strains of S. typhimurium var. Copenhagen, seven strains of S. Livingstone, one S. enteritidis and one S. infantis The S. gallinarum was isolated from dead or sick chicken (46%), eggs (10.4%), rats Rattus norvegicus (14.3%) and mattresses 1.6%. The mobile salmonellae were isolated from feedstuffs (2%), flies (14.3%), rats (2.8%), feces (1%). From the present study, it seems that rats, chicken and eggs are important for the salmonella dissemination.  相似文献   

3.
Fifteen floor litter samples were collected from each of 60 broiler chicken houses in Nova Scotia. Salmonella was recovered from 270 litter samples (30%) in 33 of 60 (55%) houses. All isolates were serotyped. Salmonella heidelberg and S. infantis were the most common of the 13 serotypes found. Isolates of selected serotypes were phage typed. Most isolates were susceptible to all common antimicrobial agents.  相似文献   

4.
为了解广东省广州市屠宰环节环境中沙门氏菌血清型分布及其耐药性,对广州市大型生猪、家禽屠宰企业环境进行监控,对比分析猪禽屠宰场污染的沙门氏菌主要血清型和耐药谱。采集屠宰场的空气、土壤、污泥样品,以及运输车辆、待宰圈/舍、屠宰车间等环境拭子样品,利用沙门氏菌特异性引物进行PCR扩增和测序鉴定;通过玻片凝集法,对PCR鉴定阳性菌落进行沙门氏菌血清分型;同时,对鉴定出的沙门氏菌进行12种抗生素耐药性分析。结果显示:55个样品池中,沙门氏菌阳性检出率为18.18%;猪禽屠宰场之间沙门氏菌污染率无显著差异(P>0.05),而不同类型样品之间差异显著(P<0.05),其中排污池污泥(75.00%)、土壤(33.33%)和屠宰车间(23.53%)污染率较高;猪屠宰场沙门氏菌优势血清型为鼠伤寒沙门氏菌(S.typhimurium),而禽屠宰场为肠炎沙门氏菌(S.enteritis);所有分离菌株对阿莫西林、氨苄西林2种抗生素完全抗药,对亚胺培南完全敏感,对头孢曲松、头孢他啶、头孢噻吩、氨曲南4种抗生素高度敏感。结果表明:猪禽屠宰场环境中,沙门氏菌污染较为严重,污泥、土壤和屠宰车间是沙门氏菌污染扩散的主要环节;猪禽屠宰场污染的沙门氏菌优势血清型并不同,且环境中污染的沙门氏菌都对部分常用抗生素产生了完全抗药。结果提示:应加强猪禽屠宰环节的沙门氏菌污染控制,将污泥、土壤、屠宰车间作为日常消毒的重点;基层应针对猪禽各自的优势血清型菌株,选用高度敏感抗生素进行沙门氏菌病防治。  相似文献   

5.
Worldwide, foodborne illness is a significant public health issue in both developed and developing countries. Salmonellosis, campylobacteriosis and shigellosis are common foodborne gastrointestinal illnesses caused by the bacteria Salmonella spp., Campylobacter spp. and Shigella spp. respectively. These zoonotic diseases are frequently linked to eggs and poultry products. The aim of this study was to investigate the presence of these pathogens in Australian backyard poultry flocks and to determine risk factors for these pathogens. Poultry faeces samples were collected from 82 backyards and screened for Salmonella spp., Campylobacter spp. and Shigella spp. using qPCR. A questionnaire was administered to the backyard poultry owners to assess their knowledge regarding management of poultry and eggs and to identify potential risk factors that may contribute to the presence of zoonotic pathogens in the flocks. One composite faecal sample was collected from each backyard (82 samples). Composite sampling here means taking one or more grab samples from a backyard to make up approximately 10 grams. Four per cent of samples, that is 4% backyards tested, were positive for Salmonella spp., 10% were positive for Campylobacter spp. and none were positive for Shigella spp. A higher infection rate was seen in multi-aged flocks (24%) compared with the single-aged flocks (3%). The survey found that many participants were engaging in risky food safety behaviours with 46% of participants responding that they washed their eggs with running water or still water instead of wiping the dirt off with a damp cloth to clean the eggs and 19% stored their eggs at room temperature. This study demonstrated that backyard poultry may pose a potential risk for salmonellosis and campylobacteriosis. Additionally, Australian public health and food safety regulations should be modified and effectively implemented to address the risks associated with backyard poultry husbandry.  相似文献   

6.
The influence of the hatchery and the poultry farm on the contamination of poultry carcases by Salmonella species has been studied by examining samples from different stages of production. The incidence of Salmonella serotypes in the hatchery varied considerably in different broiler flocks and decreased from the beginning to the end of the rearing period. Serotypes originating in the hatchery were less important in the final product than those present in the house, or those introduced into the house by vectors during rearing.  相似文献   

7.
Gast RK 《Avian diseases》2007,51(4):817-828
Of more than 2500 identified Salmonella serotypes, only a small proportion are common in poultry flocks. However, there is an epidemiologically important connection between poultry products and human infections because many of the serotypes that are most prevalent in humans (such as Salmonella Typhimurium and Salmonella Enteritidis) are similarly common in poultry. The scope of food safety efforts for poultry products has been broadened in recent years to include more attention to animal production (or preharvest) issues. The goal of preharvest poultry food safety is to minimize opportunities for the introduction, persistence, and transmission of flock infections with Salmonella and other human pathogens. This objective can be pursued either by general strategies directed against all Salmonella serotypes (and in some instances against other pathogenic microorganisms as well) or by more specific strategies that are designed to act with precision against particular Salmonella serotypes with distinctive public health or economic significance. Risk assessment studies have recommended intervention at multiple steps in the farm-to-table continuum as the most productive overall approach. A comprehensive quality assurance strategy, encompassing both broadly based risk-reduction practices and targeted testing to detect pathogens of concern, has been associated with a lower incidence of Salmonella Enteritidis infections in both egg-laying flocks and humans in a number of countries. Although the emphasis in these types of programs is primarily on risk reduction, testing provides essential verification of the efficacy and cost-effectiveness of risk-reduction practices (and identifies flocks infected with uniquely problematic serotypes). Vaccination can enhance the short-term responsiveness of control programs to address problems involving specific serotypes of elevated significance.  相似文献   

8.
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.  相似文献   

9.
Salmonella and Campylobacter are common bacterial pathogens associated with human gastro-enteritis; and raw poultry is considered to be an important source of these bacteria. To evaluate whether the Salmonella serovars and Campylobacter spp. bacteria could be monitored for the purpose of microbial presence, enumeration and antimicrobial resistance in raw poultry, 152 poultry carcasses were randomly selected from 10 markets in retail outlets of Phnom Penh during March 2006 to February 2007. The majority of poultry samples was contaminated by Salmonella serovars (88.2%) and Campylobacter spp. (80.9%). A very high contamination of Salmonella was found at 3-4 log?? CFU/g for 22.4% of samples and of Campylobacter at 7-8 log?? CFU/g for 1.3% of samples. Fifty nine different Salmonella serovars contaminated 134 poultry carcasses; five most prevalent serovars covered 29.1% of serovars isolates (Anatum, Typhimurium, Corvallis, Stanley and Enteritidis). Three Campylobacter species contaminating 123 raw poultry were Campylobacter jejuni (50.0%), Campylobacter coli (29.0%) and Campylobacter lari (21.0%). High antibiotic resistance percentages were found among Salmonella serovars and Campylobacter spp. isolates. This study revealed that raw poultry at the retail outlets in Phnom Penh markets are contaminated with high prevalences of food-borne pathogens, and communicating the importance of minimizing this risk in reducing human infections.  相似文献   

10.
About 16,000 spent hens from 23 farms in the northern area of Japan were purchased in 1996, 1997, 1998, and 1999 to isolate Salmonella in two poultry processing plants. Salmonella was detected in 12 of 23 farms (52.2%). In particular, the serotypes Enteritidis and Infantis were detected in four and three farms, respectively. The prevalence rates in the hens' ceca, immature eggs, and the yolk of mature eggs in oviducts were 14%, 7.2%, and 6.8%, respectively. A total of 23 serotypes were detected. The major serotypes of the strains were Enteritidis, Corvallis, Typhimurium, and Infantis, but most of the strains were untypable. In the same area during 1992 to 1996, Salmonella was detected in eggs associated with four outbreaks of Salmonella Enteritidis infection and one outbreak of Salmonella Infantis infection. The ratio of contamination was approximately 1%, and the level was estimated to be 93 MPN(most probable number)/100 g in one outbreak. In farms that produced the eggs associated with all of the five outbreaks of Salmonella, the serotype Enteritidis or Infantis was isolated from hens. Farms where Salmonella was not detected were not related to any of the outbreaks.  相似文献   

11.
The goal of this study was to improve the diagnostic applicability of genus- and serovar- (S. Enteritidis and S. Typhimurium) specific PCR systems in screening faecal and caecal samples of poultry, poultry feed and poultrymeat for Salmonella, by keeping the opportunity to obtain Salmonella cultures from positive samples. Peptone broth pre-enrichment cultures of the samples were tested by PCR. In faecal and caecal samples from broiler chicks a strong inhibitory action was frequently observed. This could be reduced markedly by the addition of bovine serum albumin (BSA) acting as amplification facilitator. The results of testing pre-enrichment cultures from artificially contaminated faecal, poultry feed and poultrymeat samples (using S. Enteritidis, S. Typhimurium and S. Hadar as contaminants) suggest that the sensitivity of the above systems is 10(1)-10(2) CFU g(-1) sample. The testing of 95 caecal samples from slaughtered chicks resulted in 49% culture-positive and 76% PCR-positive samples. The suitability of a generic real-time PCR for testing faecal samples of poultry was also studied. Its detection limit for these samples was found to be lower than that of the diagnostic PCR system. Both methods reduced the time required for Salmonella detection to 24-30 h, and the advantage of the real-time PCR was its increased sensitivity. We have established a diagnostic and a real-time PCR system for rapid and reliable genus- and serovar- (S. Enteritidis and S. Typhimurium) specific detection of Salmonella for monitoring purposes in the poultry food chain. Sensitivity is equal to, or higher than, that of the standard bacterial culture method, and the method still provides the Salmonella culture if needed.  相似文献   

12.
The purpose of the present study was to evaluate the prevalence and antimicrobial resistance patterns of Salmonella isolated from commercially available canine raw food diets in Canada. A total of 166 commercial frozen raw food diet samples were purchased from randomly selected local pet stores in three Canadian cities for a period of 8 months. All samples were evaluated for the presence of Salmonella, serotyped and tested for antimicrobial susceptibility. There was an overall Salmonella prevalence of 21%; chicken was an ingredient for 67% of the Salmonella-positive diets. Eighteen different Salmonella serotypes were recovered, and resistance was observed to 12 of the 16 antimicrobials tested, with the majority of Ontario isolates exhibiting resistance to ampicillin and Calgary isolates to tetracycline. This study demonstrates the potential risk of raw food diets, especially for immunocompromised individuals, and stresses the need for implementing regulatory guidelines for the production of these diets in order to help control and ideally eliminate the bacterial risks associated with their use and consumption.  相似文献   

13.
Campylobacter jejuni were isolated in large numbers from the majority of birds sampled in colonic swabs from 28 of 60 flocks at slaughter. By contrast only small numbers of birds from 11 of the same 60 flocks yielded Salmonella enteritidis serotypes. Three C. jejuni isolates from each flock were serotyped on the basis of their heat-stable antigens, using antisera prepared against 16 serotypes common in Campylobacter diarrhea in man. The majority (72 of 83) of the chicken isolates could be serotyped.  相似文献   

14.
This paper reports the susceptibility to the quinolone nalidixic acid and the fluoroquinolone ciprofloxacin of 14,514 strains of Salmonella isolated in Germany from poultry, cattle and pigs between 1998 and 2001. Quinolone-resistant salmonellae were most frequently isolated from poultry, with a prevalence of 10.2 to 16.8 per cent. Poultry-associated serotypes, such as Salmonella Paratyphi B (d-tartrate positive), Salmonella Hadar and Salmonella Virchow, had the highest prevalence of quinolone resistance, ranging between 35 and 74 per cent. All the nalidixic acid-resistant strains also had a reduced susceptibility to ciprofloxacin, with minimum inhibitory concentrations (MICS) of 0.125 to 2 microg/ml. A comparison of the MICS for ciprofloxacin of the strains of these poultry-associated serotypes and Salmonella Enteritidis phage type 4 isolated in 1998/99 and 2000/01 indicated that there had been a shift towards higher MIC values of up to 2 microg/ml. The quinolone resistance-determining region (QRDR) of the gyrA gene and the homologue region of the parC gene of 31 selected strains were sequenced. Several different amino acid changes were observed in gyrA of the quinolone-resistant isolates at positions 83 and 87, but no substitutions were observed in parC.  相似文献   

15.
Outbreaks of human salmonellosis associated with live poultry contact have been reported since 1955. Multiple Salmonella serotypes have been associated with these outbreaks, and specific outbreak strains have been repeatedly linked to single hatcheries over multiple years. During 2009, four multistate outbreaks of human Salmonella infections associated with direct and indirect exposure to live poultry purchased from mail-order hatcheries and agricultural feed stores were identified, resulting in 165 culture-confirmed cases in 30 states. This report describes the epidemiologic, environmental and laboratory investigations conducted by state and local health departments, state departments of agriculture, the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), National Poultry Improvement Plan (NPIP) and National Veterinary Services Laboratories (NVSL), and the Centers for Disease Control and Prevention (CDC). Case-patients were identified through PulseNet, the national molecular subtyping network for foodborne disease surveillance, and interviewed using the CDC standard live poultry contact questionnaire that asks about poultry-related exposures during the 7 days before illness onset. These outbreaks highlight the need to focus efforts on strategies to decrease and prevent human illness associated with live poultry contact through comprehensive interventions at the mail-order hatchery, agricultural feed store and consumer levels. Additional consumer education and interventions at mail-order hatcheries and venues where live poultry are sold, including agricultural feed stores, are necessary to prevent transmission of Salmonella from poultry to humans.  相似文献   

16.
A total of 48 environmental drag-swab samples from various poultry farms were tested for the presence of Salmonella spp. by culture, an enzyme-linked immunosorbent assay-based Salmonella antigen screening (SAS) assay, and two DNA probes (radiolabeled and colorimetric). The radiolabeled DNA probe was allowed to hybridize with culture-positive samples (n = 8) and was found to detect Salmonella spp. in all cases (100%). Both of the probes, subsequently hybridized with culture-negative samples (n = 8), were observed to yield good agreement (91%) with the culture findings. The remaining samples (n = 32) were tested by the SAS assay, and where there was no agreement between the culture and SAS, samples were further examined by the DNA probes. Results using both probes agreed with those obtained by culturing the samples but did not agree with the SAS assay result when the ratio of samples tested to samples positive (S/P) cutoff value used was 0.5.  相似文献   

17.
The objective of this study was to compare Salmonella prevalence and antimicrobial resistance between pasture and conventional poultry farms. We collected the first Salmonella prevalence and antimicrobial resistance data on pasture poultry farms. Fecal droppings were collected from 31 farms from Wisconsin (nine farms from each production type) and the Southeast (North Carolina, Virginia, and South Carolina; five conventional and 10 pasture poultry farms) in a 1-yr period. The specimens were cultured for Salmonella and tested for resistance to 12 antimicrobials. A univariate analysis was conducted to determine the significant differences in prevalence and resistance. At the farm level, no significant difference in Salmonella prevalence was found on 33% pasture and 47% conventional poultry farms (P= 0.4928). On an individual specimen level, flocks reared conventionally had higher prevalence than in pasture (P < 0.0001). Of all the isolates found to have resistance, 80% were from the Southeast. Of all the pasture isolates tested, 5% (8 of 162) were resistant to ceftriaxone, which is higher than previously reported from any production setting. None of the isolates from conventional flocks showed resistance to ceftriaxone. Multidrug resistance (resistance to three or more classes of antimicrobials) was found in 69% of the isolates from conventional farms and 11% on pasture farms in the Southeast (P < 0.0001), with the predominant resistance type of AmCSSuTeAx (ampicillin, chloramphenicol, streptomycin, sulfasoxazole, tetracycline, amoxicillin/clavulanic acid; 62%). About 5% of the pasture isolates from the Southeast showed the AmAxCFCRO (ampicillin, amoxicillin/clavulanic acid, cephalothin, ceftriaxone) multidrug resistance pattern. None of the isolates from Wisconsin were found to be multidrug resistant.  相似文献   

18.
A conventional method of isolating Salmonella was compared with isolation using novobiocin-supplemented plating media and delayed secondary enrichment (DSE). The DSE greatly increased the ability to isolate Salmonella from poultry and environmental samples. Four hundred sixty-four isolations of Salmonella were made from a total of 4377 cultures (11%). Two hundred sixty-nine (58%) isolations of Salmonella were made following the 24-hour incubation; of these, 43 (9%) isolates were isolated only at this time. In comparison, a total of 421 (91%) Salmonella were isolated by DSE, of which 195 isolates (42%) were isolated only with DSE. The addition of novobiocin to the selective plating medium increased the isolation rate for Salmonella and reduced the level of contaminating bacteria growing on the plate.  相似文献   

19.
The phase 1 (fliC) and phase 2 (fljB) Salmonella flagella genes were analyzed by restriction fragment length polymorphism (RFLP)-polymerase chain reaction (PCR) to aid in the identification of different Salmonella serotypes. Twenty-four phase 1 flagellin and eight phase 2 flagellin genes could be differentiated among each other with restriction endonucleases Sau3A and HhaI in RFLP-PCR analysis. These flagellin genes comprise the major antigenic formulas for 52 serotypes of Salmonella sp., which include the common serotypes found in poultry and other important food animal species. With the knowledge of the O antigen composition determined from conventional O serotyping, 90% of the Salmonella serotypes could be identified by this double restriction enzyme RFLP analysis of fliC and fljB genes. This RFLP-PCR flagellar typing scheme was successfully applied to the identification of serotype for 112 Salmonella isolates obtained from poultry environment. There was a significant correlation between RFLP-PCR and conventional serotyping (chi-square, P < 0.001). Overall, PCR-RFLP proved to be a fast, accurate, and economical alternative approach to serotyping Salmonella sp.  相似文献   

20.
Eighty-six Salmonella enteritidis isolates obtained during a surveillance program of poultry farms in Maine were subjected to phage-typing, plasmid profiling and fingerprinting, outer-membrane polypeptide analysis, and antimicrobial sensitivity testing. Isolates were obtained from a variety of sources, including poultry-farm environmental samples, chicken organ samples, human stool samples, cat feces, and live-trapped rats and mice. These isolates were compared with 21 S. enteritidis isolates originating outside of Maine. Phage types isolated in Maine included 13a (60%); 14b (29%); 23 (5%); 8 (2%); and 2 (2%). All S. enteritidis isolates from Maine carried plasmid DNA, and 97% of these isolates carried a 40.3-megadalton plasmid alone (6%) or in conjunction with several smaller plasmids (91%). All 52 phage-type 13a isolates harbored 40.3- and 3.0-megadalton plasmids. All 25 phage-type 14b isolates carried 3.3- and 1.3-megadalton plasmids, and 22 isolates also carried the 40.3-megadalton plasmid. All isolates displayed highly similar outer-membrane polypeptide profiles and were sensitive to a variety of antimicrobials commonly used against gram-negative organisms. The above data suggest that phage type and plasmid content may be related in the cases of phage-type 13a and 14b isolates, and that traditional plasmid-borne antimicrobial resistance determinants were not present in Maine isolates. Results also indicate that phage-typing can be a valuable epizootiological tool for monitoring the potential spread of these strains throughout the Northeast.  相似文献   

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