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1.
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   

2.
The survival period of 22 S. gallinarum strains in chicken feces was examined. The suspension of the bacterium was homogenized with a certain feces quantity. The initial ratio was 10(7) to 10(9) colony forming units per gram of feces. The results show that the growth of 5 strains was completely inhibited within 24 hours post homogenization, 7 strains were still positive to S. gallinarum for 24 hours, 5 strains were positive for 48 hours and the last 5 strains were positive for 4 days. Additionally, the effect of tryptose soy (TSB) and Rappaport-Vassiliadis (RV) nutrient broths on the isolation rate of S. gallinarum from feces was examined at 37 degrees C and 43 degrees C. It was shown that the TSB medium was the best at 37 degrees C, in this experiment. The S. gallinarum concentration in RV medium was decreased at 37 degrees C from 9.1 x 10(8) to 1.6 x 10(6) and at 43 degrees C from 9.1 x 10(8) to 4.1 x 10(2).  相似文献   

3.
A microbiological survey of 10 mice-infested poultry farms was conducted to determine the role of mice in the epizootiology of S. enteritidis infection. Five of the farms were rated as clean of S. enteritidis and five as contaminated based on culture results of environmental samples for S. enteritidis. Of 2103 environmental samples and 715 mice and rats tested, 5.1% and 16.2%, respectively, were culture-positive for S. enteritidis. On contaminated farms, S. enteritidis was isolated from 24.0% of the mice and 7.5% of the environmental samples, which represented 75.3% of all Salmonella isolations from mice but only 18.0% of Salmonella isolations from environmental samples on these farms. S. enteritidis was not detected in mice on clean farms. Phage types 13a and 14b were the two most frequently isolated phage types from mice and environmental samples. Although only a single phage type was isolated from single free-standing poultry houses, multiple phage types were isolated from multi-house complexes. A bacterial count from the feces of one mouse yielded 2.3 x 10(5) S. enteritidis bacteria per fecal pellet. S. enteritidis persisted at least for 10 months in an infected mouse population.  相似文献   

4.
This study investigated the differences in Salmonella isolation rates in environmental samples taken from several types of hen houses in Chiba, Japan. In addition, for the detailed epidemiologic survey, environmental samples, hens, and rodents were collected from Salmonella-contaminated windowless houses on three farms. As a result, Salmonella was isolated from four (80%) of five farms with windowless hen houses; Salmonella enteritidis was isolated from a single windowless house. In contrast, only one serotype of Salmonella was isolated from 1 (6.7%) of 15 farms with open hen houses. In the S. enteritidis-contaminated windowless hen house, the isolation rates of S. enteritidis as compared with the other serotypes were 90.9% of environments, 94.1% of hens, and 86.4% of roof rats (Rattus rattus) that resided in the environments. In reference to the phage type (PT) of these isolates, PT1 was detected in environments and roof rats, and PT9 was detected in both these samples and in hens. Thus, the Salmonella isolation rate in hen houses seems to be associated with whether the premises are windowless or open. Moreover, roof rats appear to be the most important vectors in the spread of S. enteritidis in the windowless hen house because the S. enteritidis PTs coincide with each other.  相似文献   

5.
The growth of Salmonella Choleraesuis was examined in Rappaport Vassiliadis broth (RV) and Hajna-tetrathionate broth (HTT) at 37 and 42 degrees C. As the enrichment in RV at 37 degrees C was satisfactory for isolating S. Choleraesuis, we used this enrichment for isolation from the samples collected from 15 asymptomatic pigs reared on a S. Choleraesuis contaminated farm. S. Choleraesuis was frequently isolated from six pigs (40.0%) under field conditions. The isolation of other Salmonella serovars than S. Choleraesuis was attempted by using both RV enrichment at 37 degrees C and HTT enrichment at 42 degrees C. Salmonella organisms were isolated from 156 (44.8%) of 348 fecal samples and more frequently with HTT at 42 degrees C (43.4%) than with RV at 37 degrees C (20.9%). If other serovars in addition to S. Choleraesuis are to be surveyed, HTT enrichment should be used in combination with RV enrichment.  相似文献   

6.
Rodents play a major role in the transmission and maintenance of Salmonella contamination cycles in poultry facilities. However, very limited field data are available regarding the transmission routes, infection cycle, and shedding patterns of Salmonella by naturally infected wild rodents from commercial layer farms. In this study, a total of 128 resident wild roof rats (Rattus ratus) were captured from a Salmonella-contaminated layer facility. All roof rats were divided into 51 laboratory cages, and weekly monitoring of Salmonella fecal shedding patterns was conducted for 53 wk. Seven roof rats from cages that were observed to frequently shed Salmonella were isolated in individual cages, and daily Salmonella monitoring was performed for 35 days. At the end of monitoring, each roof rat was euthanatized, and isolation of Salmonella from different organs was performed. Results of weekly monitoring of Salmonella showed that 21 of 51 cages (41.2%) were positive for Salmonella Infantis, while two cages (3.92%) were positive for Salmonella Enteritidis. Moreover, 11 cages were positive for Salmonella for at least two sampling weeks. Isolation of Salmonella from fecal droppings was mainly observed during the first 12 wk of captivity. The longest interval between two Salmonella-positive fecal dropping was 24 wk. In the daily Salmonella monitoring, only Salmonella Infantis was isolated from fecal droppings, in which the highest number of Salmonella Infantis organisms per fecal dropping was at 1 x 10(8) colony-forming units (cfu), while the lowest measured quantity was 1 x 10(3) cfu. It was noted that the frequency of Salmonella shedding in fecal droppings appeared to have a linear correlation (r = 0.85) with the number of Salmonella organisms (cfu) per fecal pellet (P < 0.05). Moreover, pulsed-field gel electrophoresis analysis of Salmonella Infantis isolates revealed a single identical pulsed-field pattern. Salmonella Enteritidis isolates from fecal droppings and internal organs also generated a single identical pulsed-field pattern. Interestingly, Salmonella Infantis was not isolated from any of the organs examined, while Salmonella Enteritidis was isolated from the spleen and liver of one roof rat. These results may indicate that wild roof rats could persistently carry Salmonella and contaminate commercial poultry facilities through intermittent fecal shedding. Moreover, Salmonella Enteritidis in wild roof rats appears to be more of a systemic infection, in which isolation is most likely to occur in internal organs, whereas Salmonella Infantis is more likely an enteric type of infection, in which isolation is most likely to occur in the intestinal contents. It is very plausible that layer chickens could become infected with Salmonella through ingestion of Salmonella-positive fecal droppings or feeds contaminated with these fecal droppings from infected resident roof rats. This is likely one of the major reasons why layer houses can be persistently infected by Salmonella even if the facilities are thoroughly cleaned and disinfected and if replacement stocks are obtained from Salmonella-free breeders and rearing units. It is therefore a noteworthy suggestion that rodent control programs inside poultry premises comprise an essential and effective tool in the management and control of Salmonella contamination in layer flocks.  相似文献   

7.
The intestinal tracts of twenty inbred SPF rats (LEW, BN, WKY, DA) and six wild Norway rats (Rattus norvegicus Berkenhout 1769) were investigated for mycoplasmas. Cultivation was in three different media. Mycoplasmas were not isolated from the intestine of the inbred SPF rats but were found in the epithelia and contents of caecum, colon and jejunum as well as in fecal samples of all of the wild Norway rats investigated. The mycoplasmas isolated all belonged to the same species, and were identified as Mycoplasma moatsii, originally isolated from grivit monkeys (Cercopithecus aethiops) and thought to be specific for this host.  相似文献   

8.
Several methods were evaluated for collecting fecal and intestinal samples from wild birds found near broiler chicken houses. A few intestinal samples and cloacal swabs were obtained from European starlings and house sparrows. Most of the samples collected consisted of wild bird droppings found on or near the houses. Samples were collected from each of four farms of a broiler integrator during a grow-out cycle: a cycle in the summer for farm A, fall for farm B, and spring, summer, fall, and winter for farms C and D. Of the 25 wild bird intestinal and fecal samples collected from a broiler house on farm A during a grow-out cycle in July-August 1997, 24% were positive for Salmonella spp., 4% for Campylobacter jejuni, and 28% for Clostridium perfringens. Of the nine fecal samples collected from broiler house B in a grow-out cycle in September-November 1997, 33% were positive for Salmonella spp., 11% for C. jejuni, and 22% for C. perfringens. For farms C and D, of the 23 samples collected in March-April 1998, 0 were positive for Salmonella spp., 11% for C. jejuni, and 52% for C. perfringens; of 27 samples collected in June-July 1998, 4% were positive for Salmonella spp., 0 for C. jejuni, and 13% for C. perfringens; of 24 samples collected in August-October 1998, 14% were positive for Salmonella spp., 5% for C. jejuni, and 4% for C. perfringens; of 14 samples collected December 1998-January 1999, 0 were positive for Salmonella, 50% for C. jejuni, and 14% for C. perfringens. The incidence of these bacterial enteropathogens in wild birds near the broiler chicken houses suggests that wild birds that gain entry to poultry grow-out houses have the potential to transmit these pathogens to poultry.  相似文献   

9.
The Q fever outbreak in the Netherlands in 2007-2010 prompted government interventions to reduce the human incidence by reduction of Q fever shedding at dairy goat farms. Mandatory hygiene measures were taken, including the control of animal reservoirs. It has been postulated that brown rats, through their commensal nature, form an important factor in the persistent dissemination of endemic circulating Coxiella burnetii in nature to domestic animals, livestock and humans. Here, the occurrence of C. burnetii in rats captured at different types of location during the Q fever outbreak in the Netherlands, viz. urban areas, nature areas and various types of farm has been determined. This is a first step towards the elucidation of the reservoir status of rats in veterinary and human Q fever epidemiology. C. burnetii DNA was detected in the spleen of 4.9% of the brown rats (Rattus norvegicus) and 3.0% of the black rats (Rattus rattus). Evidence for C. burnetii infection was also found in liver, kidney, lung and intestinal tissue but not in heart, brain and pancreas. C. burnetii IgGs were detected in 15.8% of the brown rats. Positive rats were collected at goat, pig, cattle and poultry farms, and urban locations; including locations outside the designated 5km "increased-risk" zones around bulk milk positive goat farms. The percentage of rat-positive locations was the highest for goat farms (50%) and cattle farms (14.3%). The presence of actively infected rats outside the lambing season and at multiple environmental settings including urban locations might suggest that rats are not merely a spill-over host due to infection by a contaminated environment but might represent true reservoirs, capable of independent maintenance of C. burnetii infection cycles and thereby contributing to spread and transmission of the pathogen. If frequent (re)introduction of C. burnetii to small ruminant farms can be caused by rats as maintenance reservoirs, mandatory wildlife control and lifelong vaccination of herds will be necessary.  相似文献   

10.
Salmonella gallinarum is gram-negative bacteria that cause fowl typhoid (FT) in chickens. Since the first outbreak of FT reported in 1992 in Korea, it has widely spread throughout the country. Today, FT is one of the most devastating diseases of poultry. The aim of the present study was to ascertain a genetic relationship among S. gallinarum isolates collected from different regions of Korea over a 10-year period. We examined a total of 38 isolates of S. gallinarum obtained in 29 regions of Korea from 1992 to 2001 including the 9R vaccine strain and the standard strain of S. gallinarum (ATCC 9184). The PFGE profiles produced 12 different patterns with the XbaI-digestion and 11 different patterns with the SpeI-digestion. The RAPD using URP-6 primers showed eight different genotypes with the same Salmonella isolates. The PFGE patterns of the 9R vaccine strain and ATCC 9184 of S. gallinarum were different from the identical type A, the most common genotype among field isolates in our study. In conclusion, a low genetic heterogeneity was observed among Korean S. gallinarum isolates. In addition, PFGE appeared to be a more accurate and reproducible method for genotyping of S. gallinarum isolates than RAPD.  相似文献   

11.
Between August 20, 2001, and September 17, 2002, 1429 samples including drag swabs, egg belt or egg rollout swabs, fan-blade swabs, rodent organ and intestinal pools, beetle (Alphitobius diaperinus) pools, housefly (Musca domestica) pools, chicken organ and intestinal pools, and egg pools were obtained for Salmonella culture from two flocks from two different commercial layer ranches. The two ranches were purposefully selected for the study based on their previous status of Salmonella Enteritidis isolation using environmental drag swabs in cooperation with practicing veterinarians. Salmonella sp. was isolated from 337 out of 979 (34.42%) non-egg samples. No Salmonella was isolated from 450 egg pools collected from either ranch. S. enteritidis was isolated from samples obtained from ranch 1 from manure drag swabs, 4/284 (1.4%); rodent organs, 1/24 (4.2%); and housefly pool cultures 1/21 (4.8%). Salmonella Enteritidis was isolated from ranch 2 from mouse organ and intestinal pool samples, 1/24 (4.2%). Salmonella group B was isolated from all sample types except the insects. There was a statistically significant difference in isolation rates among seven serogroups of Salmonella: groups B, C1, C2, D, E, K, and untypeable (Pearson chi-square 18.96, P = 0.002). Overall, statistically significant differences were observed with respect to Salmonella isolation among the types of samples taken (Pearson chi-square 118.54, P < 0.0001). Intensive monitoring for Salmonella Enteritidis can be used to optimize a Salmonella reduction program for an individual poultry biosecurity unit.  相似文献   

12.
北京地区健康肉鸡携带沙门氏菌状况调查   总被引：1，自引：0，他引：1  
禽源沙门氏菌是一种重要的人畜共患病原菌和食源性病原菌。肉鸡作为人肠炎沙门氏菌感染的主要来源,目前国内对其沙门氏菌携带状况的研究资料较少。为了解北京地区健康肉鸡中沙门氏菌的携带情况,本研究共采集该地区28个肉鸡养殖场的盲肠或泄殖腔拭子样品1310份,进行沙门氏菌的分离和鉴定,总共分离出沙门氏菌54株。血清分型结果表明,肠炎和爪哇安那为两种优势血清型,所占比例分别为31.5%和25.9%;其次是禽伤寒,占比9.3%。本研究为北京地区肉鸡场沙门氏菌病的防控及首都公共卫生安全提供了基础资料。  相似文献   

13.
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.  相似文献   

14.
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   

15.
A total of 1,013 feces samples and 8 mesenteric lymphonodus samples obtained from apparently healthy dogs were examined for the incidence of salmonella infection. One strain of S. typhimurium (ST) was isolated from feces of one dog, and S. enteritidis (SE) was isolated from the mesenteric lymphonodus of one dog. Sera obtained from 330 apparently healthy dogs were examined for Salmonella antibodies using an ELISA with heated whole cells of SE and ST. Fifty-one of the 330 serum samples were considered to be positive for salmonella antibodies, including 12 which were SE-positive and 39 which were ST-positive. These results indicate that dogs cause possible environmental problems as Salmonella carriers.  相似文献   

16.
Seventy-five pigs from 4 facilities were examined for Salmonella choleraesuis by use of bacteriologic culture of feces, blood, WBC (buffy coat), mononuclear leukocytes, and neutrophils. The organism was isolated from 0 of 75 fecal samples, compared with isolation from 39 of 75 purified neutrophil preparations. Of the pigs that did not have Salmonella isolated from feces or blood, but had S choleraesuis isolated from neutrophils, 6 were further examined. These pigs from 2 groups again had culture performed at least 3 successive times to test for repeatability and to determine optimal number of neutrophils required for Salmonella isolation. These same pigs were euthanatized and necropsied. Nineteen tissue specimens from each pig were obtained for culture, but S choleraesuis was isolated only from neutrophil samples. Results indicate that neutrophils may contribute to the carrier state in pigs and should be cultured when attempting to identify S choleraesuis carrier swine.  相似文献   

17.
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   

18.
Approximately 200 opossums, trapped during the fall of 1973 in the vicinity of Raleigh, NC, were maintained in the Institute's breeding colony in individual cages until the breeding season. Clinically normal, dead, and moribund opossums were examined for Salmonella. Six serotypes of Salmonella were identified in both clinically normal and diseased opossums. Positive culture results were obtained on 39 of 56 (70%) rectal swab specimens collected in the fall from incoming opossums, and on 30 of 50 (60%) rectal swab specimens collected during midwinter from an additional group of clinically normal opossums, which were maintained in isolation for approximately 3 months before testing. At necropsy, 87 of 108 (81%) diseased opossums were culture positive for Salmonella. Salmonellae in serogroups B and R were isolated from the spleen, liver, kidneys, or heart blood as well as the ileum of 57 diseased opossums. In 23 cases, S typhimurium or S bern was isolated in pure culture from the visceral organs. These findings indicated bacterial septicemia. In contrast, salmonellae in serogroups C1, E1, and F were routinely isolated from the feces of clinically normal and diseased opossums, suggesting a habitat restricted to the intestinal tract and probably the mesenteric lymph nodes. It was concluded that the opossum serves as a reservoir for a number of serotypes of Salmonella and may have an important role in the epizootiology of wildlife salmonellosis.  相似文献   

19.
An ELISA using lipopolysaccharide antigens prepared from Salmonella gallinarum and S enteritidis was developed for the serological diagnosis of fowl typhoid and S enteritidis infection in poultry. There was good agreement between the results of the ELISA and conventional serological tests when samples from naturally infected birds and S enteritidis immunised birds were tested. Some cross reactions were observed when serum samples from S typhimurium infected birds were tested by ELISA. Subsequently a disc ELISA, using filter paper discs, was developed to facilitate sampling and testing of poultry. There was good correlation between the results of the disc and serum ELISAs and the test is recommended for the field testing of birds.  相似文献   

20.
Prevention of Salmonella contamination of poultry products requires detailed knowledge of the main sources associated with its presence in the production system. The aims of this study were to determine the main sources of Salmonella contamination in broiler production during growing, to assess the risk factors for Salmonella contamination at the end of the rearing period and to determine the main serovars involved in broiler production systems in Eastern Spain. A total of 65 different broiler houses from different farms were sampled. Each house was sampled at different times during the rearing period. First, when the previous flock was taken to the slaughterhouse, samples of dust, surfaces and previous flock faeces were collected. After cleaning and disinfection (C&D), samples of dust and surfaces were also taken. On the first day of rearing, samples of water, bedding, farming boots, meconiums, delivery-box liners and feed were collected. During rearing, feed samples were taken directly from the truck and from feeders. On slaughter day, samples of dust, surfaces, water, feed and faeces were also collected. Finally, two days after slaughter, carriers (rodents, flies and beetles) were trapped. All samples collected were analysed according to ISO 6579:2002 (Annex D) and positive samples were serotyped in accordance with Kauffman-White-Le-Minor technique. Our results showed that all different types of samples collected were contaminated with Salmonella (prevalence ranged between 1.5% and 38.6%). The most contaminated samples related with poultry production were: delivery-box liners (32.0%), faeces samples (31.2%), dust samples (25.0%), farming boots (19.7%) and feed from feeders (16.0%). However, the most important risk factors for Salmonella contamination of the flocks at the end of the rearing period were Salmonella status of the house after cleaning and disinfection, Salmonella status of day-old chick flocks and feed from feeders. Twenty-one different serovars were isolated from the samples analysed. The most prevalent were in decreasing order: Salmonella Enteritidis (52.9%), S. Hadar (17.8%), S. Virchow (8.9%) and S. Ohio (5.4%). The study suggested that there are many sources for Salmonella contamination and persistence in broiler production. Hence, the whole production chain needs to be controlled to eradicate the bacteria from primary production.  相似文献   

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