首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 46 毫秒
1.
From winter 1997 to summer 1998, an epizootic of salmonellosis affected several species of songbirds over a large area of the eastern North American continent. This article describes the details of this epizootic in the Canadian Atlantic provinces, based on laboratory examination of dead affected birds and on suspected but unconfirmed cases of salmonellosis reported by members of the public. The common redpoll (Carduelis flammea) was the species most often affected, followed by pine siskins (C. pinus), purple finches (Carpodacus purpureus), evening grosbeaks (Coccothraustes vespertinus), and American goldfinches (Carduelis tristis). A poor body condition and necrotizing and fibrinopurulent esophagitis and ingluvitis were the most common gross lesions in these birds. Thirty-four of 35 isolates of Salmonella recovered from these birds were identified as phage type 40. Despite the magnitude of this and previous epizootics of salmonellosis among North American songbirds, the sources of these epizootics and the precise influence of environmental factors on their occurrence remain poorly understood.  相似文献   

2.
Salmonella enterica subspecies enterica serotype Typhimurium and Escherchia coli O86:K61:NM are two bacteria that can cause outbreaks of mortality in garden birds visiting bird tables and other feeding stations. Two sites in south-west Scotland were monitored for the two organisms for 12 months. At site A, large numbers of birds fed throughout the year, and at site B smaller numbers of birds fed only in the winter months. Samples of composite faeces were collected from the feeding stations and screened for the organisms, and any dead birds were also screened. S Typhimurium definitive type (DT) 56 (variant) was found to be endemic at site A, and was recovered from 48 per cent of samples of composite faeces collected from the bird table, from 42 per cent of composite faeces from underneath a hanging feeder, and from 33 per cent of composite faeces from below a roost used by house sparrows; the organism was also isolated from the carcases of six wild birds found dead at the site. In contrast, S Typhimurium (DT41) was recovered only once at site B, from 2 per cent of the composite faeces from below a hanging feeder, and no dead birds were recovered from the site. E coli O86 was not recovered from the faeces collected from either site, but was isolated from a bird that died from trauma at site A.  相似文献   

3.
Pooled faeces collected from a garden bird table were screened for Salmonella species and Escherichia coli O86, two recognised causes of garden bird mortality. Dead birds found at the site were also screened for these organisms, and bird numbers and meteorological data were recorded. In the first year of the study, 48.5 per cent of the samples were positive for Salmonella Typhimurium DT56 (variant), decreasing to 38.9 per cent in the second year and 12.8 per cent in the third year. E. coli O86 was not recovered from any of the 288 samples of pooled faeces tested. S. Typhimurium DT56 (variant) was recovered from the carcases of eight birds found dead at the site, and E. coli O86 was isolated from three carcases. The degree of contamination of the bird table with S. Typhimurium DT56 (variant) was positively correlated with the number of house sparrows observed in the garden, but not with the number of blackbirds, chaffinches or greenfinches.  相似文献   

4.
AIM: To examine the infective dose, incubation period and disease progression of an isolate of Salmonella enterica serotype Typhimurium definitive type 160 (DT160) originating from a naturally-infected house sparrow (Passer domesticus) during an outbreak of the disease in New Zealand. METHODS: Thirty-six house sparrows captured from the wild and free of Salmonella spp were divided into six groups of six birds, housed individually, and inoculated orally with phosphate buffered saline (PBS) or 10(1), 10(2), 10(3), 10(5), 2 x 10(8) colony forming units (cfu) of the outbreak strain of S. Typhimurium DT160. The birds were observed for 10 days for clinical signs and/or mortality, and faecal samples were collected to determine excretion of S. Typhimurium. The birds were euthanised 11 days post-inoculation (p.i.) and a wide range of tissue samples were collected for histopathological examination, and culture and typing of Salmonella spp. Macro-restriction profiling by pulsed-field gel electrophoresis (PFGE) using XbaI was performed for the epidemiological typing of S. Typhimurium DT160 isolates. RESULTS: Mortality in house sparrows inoculated with S. Typhimurium DT160 was dose-dependent, and 2/6 birds inoculated with 10(5) cfu and all six birds inoculated with 2 x 10(8) cfu died during the study. Infected sparrows displayed few clinical signs, apart from diarrhoea and/or polyuria, fluffed plumage, and sitting on the floor of the cage. Faecal excretion of DT160 occurred briefly in two birds inoculated with 10(2) cfu and four birds inoculated with 10(3) cfu, on most days in five birds inoculated with 10(5) cfu, and continuously in six birds inoculated with 2 x 10(8) cfu. DT160 was isolated from the livers of three birds which received 10(3) cfu, five birds dosed with 10(5) cfu, and all six birds given 2 x 10(8) cfu. Following necropsy, histopathological lesions similar to those seen in the natural disease were observed in the liver or spleen of three birds which received 10(3) cfu, and all birds dosed with > or =10(5) cfu. CONCLUSION: The results indicate that an isolate of S. Typhimurium DT60 originating from house sparrows in New Zealand is pathogenic to these birds and that the response is dose dependent. The persistence and excretion of the pathogen may last for at least 10 days. This confirms that sparrows infected with DT160 could be a source of infection to humans and other in-contact animals.  相似文献   

5.
AIM: This study reports an outbreak of salmonellosis due to S. Typhimurium DT160 which caused extensive mortality in wild birds and enteric disease in humans in New Zealand during the winter and spring months of the year 2000. METHODS: Necropsies were performed and microbiological examinations undertaken on wild birds from populations in which mass mortality was reported, and on captive indigenous birds which died suddenly during the winter and spring of 2000. Affected tissues were examined histologically and isolates of S. Typhimurium were phage typed and examined using pulsedfield gel electrophoresis (PFGE). Isolates of S. Typhimurium obtained from cases of human enteric disease which occurred during these months were phage typed, examined using PFGE and compared with the bird isolates. RESULTS: Central and northern areas of the South Island and the southern North Island were worst affected with die-offs of several hundreds of sparrows and other birds reported in rural areas. Mortalities reached a peak in winter (July-August) 2000 and decreased to small numbers during the spring and early summer. The birds usually died of an acute septicaemia with multifocal necrotising lesions in the liver and spleen. Human cases throughout the country increased gradually over the same period. Isolates from birds, livestock and humans examined using PFGE were indistinguishable from one another. CONCLUSION: This strain of Salmonellahas emerged as a major cause of septicaemia in wild birds in New Zealand. Because of the close association between house sparrows (Passer domesticus) and humans, the organism also poses a serious zoonotic risk. The possibility that the infection may spread to involve indigenous species needs investigation.  相似文献   

6.
The role of birds as sources of Shiga toxin-and intimin-producing Escherichia coli was studied. Fecal samples from live gulls (n=86), pigeons (n=33) and broiler chickens (n=199) from 23 flocks were analyzed for stx and eae by PCR. No stx positive samples were detected. In contrast, eae E. coli were highly prevalent among gulls (40%), and was also found in pigeons (7%) and chickens (57% of the flocks contaminated). The eae positive isolates were analyzed genetically and O-serogrouped. One isolate from a pigeon was found to have stx (2f). The isolates of gulls differed from those of pigeons and chickens, and all eae E. coli isolates from birds differed from human pathogenic strains by the lack of EHEC-hlyA and bfp/EAF as well as distribution of O-serogroups. Thus, birds cannot be regarded as important carriers of zoonotic stx or eae E. coli in Finland.  相似文献   

7.
Resistance to 16 antimicrobial agents was monitored in 109,125 Salmonella cultures isolated from animals, their environment and feedstuffs between 1988 and 1999. The sensitivity of the 6512 isolates of Salmonella enterica enterica serotype Dublin to all the antimicrobial agents tested varied from 98.2 per cent in 1997 to 99.7 per cent in 1990 and 1996. In contrast, among 28,053 isolates of Salmonella enterica enterica serotype Typhimurium, there was a marked decrease in their sensitivity to all the antimicrobial agents tested, from 57.4 per cent in 1992 to 7.6 per cent in 1995, owing to the widespread occurrence in farm animals of S Typhimurium isolates of the definitive type DT104, resistant to ampicillin, sulphonamides, streptomycin, chloramphenicol and tetracyclines, although the percentage of sensitive isolates increased to 18.4 per cent in 1999, when the incidence of DT104 had decreased. Some isolates of DT104 also showed an increase in resistance to potentiated sulphonamides (2.4 per cent in 1989 to 19.2 per cent in 1999) and nalidixic acid (0 per cent in 1992, 3.8 per cent in 1995 to a peak of 16.9 per cent in 1998). In 1996, 5.1 per cent of 1086 isolates of S Typhimurium from cattle and 35.9 per cent of 192 isolates of S Typhimurium from poultry showed resistance to nalidixic acid. Of the other 74,528 Salmonella isolates, the percentage of strains sensitive to all the antimicrobials tested decreased slightly from 88.2 per cent in 1988 to 70.6 per cent in 1996 and then increased slightly to 73.7 per cent in 1999. The commonest of these other Salmonella serotypes was Salmonella Enteritidis (20,982), which remained predominantly susceptible (ranging from 81.4 to 97.4 per cent) during the study period. Few isolates were resistant to commonly used veterinary antimicrobials, for example, furazolidone, the use of which was banned in 1990, and the aminoglycoside, apramycin.  相似文献   

8.
Salmonella typhimurium was isolated from nine of 60 wild sparrows trapped in the Guelph area. While this organism was isolated from birds trapped at several different locations, the highest prevalence was in sparrows trapped in close proximity to an animal clinic. The significance of these findings in relation to human and animal salmonellosis is discussed.  相似文献   

9.
AIM: To examine the infective dose, incubation period and disease progression of an isolate of Salmonella enterica serotype Typhimurium definitive type 160 (DT160) originating from a naturally-infected house sparrow (Passer domesticus) during an outbreak of the disease in New Zealand.

METHODS: Thirty-six house sparrows captured from the wild and free of Salmonella spp were divided into six groups of six birds, housed individually, and inoculated orally with phosphate buffered saline (PBS) or 101, 102, 103, 105, 2 × 108 colony forming units (cfu) of the outbreak strain of S. Typhimurium DT160. The birds were observed for 10 days for clinical signs and/or mortality, and faecal samples were collected to determine excretion of S. Typhimurium. The birds were eutha- nised 11 days post-inoculation (p.i.) and a wide range of tissue samples were collected for histopathological examination, and culture and typing of Salmonella spp. Macro-restriction profiling by pulsed-field gel electrophoresis (PFGE) using XbaI was performed for the epidemiological typing of S. Typhimurium DT160 isolates.

RESULTS: Mortality in house sparrows inoculated with S. Typhimurium DT160 was dose-dependent, and 2/6 birds inoculated with 105 cfu and all six birds inoculated with 2 × 108 cfu died during the study. Infected sparrows displayed few clinical signs, apart from diarrhoea and/or polyuria, fluffed plumage, and sitting on the floor of the cage. Faecal excretion of DT160 occurred briefly in two birds inoculated with 102 cfu and four birds inoculated with 103 cfu, on most days in five birds inoculated with 105 cfu, and continuously in six birds inoculated with 2 × 108 cfu. DT160 was isolated from the livers of three birds which received 103 cfu, five birds dosed with 105 cfu, and all six birds given 2 × 108 cfu. Following necropsy, histopathological lesions similar to those seen in the natural disease were observed in the liver or spleen of three birds which received 103 cfu, and all birds dosed with ≥105 cfu.

CONCLUSION: The results indicate that an isolate of S. Typhimurium DT60 originating from house sparrows in New Zealand is pathogenic to these birds and that the response is dose- dependent. The persistence and excretion of the pathogen may last for at least 10 days. This confirms that sparrows infected with DT160 could be a source of infection to humans and other in-contact animals.  相似文献   

10.
  相似文献   

11.
On the occasion of a large exhibition of pure-breed fancy pigeons 398 animals from 49 different dovecotes were examined for Salmonella shedding. Faecal samples were taken after caging of the birds for the exhibition and after 3 days, before the end of the exhibition. Salmonella were detected in faeces of 28 out of 398 pigeons (7.04%). 10 birds were Salmonella positive only after caging for the exhibition, 10 other animals only before the end of the exhibition, and 8 pigeons at both occasions. The Salmonella positive birds originated from 15 different dovecotes, i.e. in ca. 30% of the dovecotes at the exhibition at least 1 Salmonella positive pigeon was identified. The share of positive birds in these dovecotes varied between 5% and 83%. All Salmonella isolates belonged to the serovar Typhimurium variant copenhagen and were of phage type DT 2. The results of this study do not provide complete evidence on the spreading of Salmonella organisms from birds infected at time of caging to other pigeons during the exhibition, however, such transmission cannot be excluded. In only 18 dovecotes pigeons were immunised against Salmonella Typhimurium. However, in these dovecotes all breeder birds but only 13% of the young pigeons had been immunised. Among the vaccinated breeder pigeons the number of Salmonella positive birds was considerably lower (not significant) than among the non-vaccinated breeders. There is epidemiological evidence that vaccination of pigeons has a considerable protective effect against Salmonella exposure. However, in order to effectively reduce Salmonella findings in pure-breed fancy pigeons it is recommended to provide vaccination to pigeons in a greater number of dovecotes and to include the progeny, too.  相似文献   

12.
Since 1994, an epidemic of conjunctivitis caused by Mycoplasma gallisepticum (MG) has spread throughout the eastern population of house finches (Carpodacus mexicanus). The adaptation of MG to a free-flying avian species presents potential problems for the control of mycoplasmosis in commercial poultry. To evaluate risks associated with this emerging problem, a field survey was conducted to assess prevalence of MG infection in house finches and other passerine birds associated with poultry farms. Between November 1997 and March 1999, 1058 birds were captured by mist net or trap at 17 farms and at 10 feeder stations in northeast Georgia. Birds were bled and screened by serum plate agglutination (SPA) for antibodies to MG. Birds with negative or weak positive SPA results were released at capture sites, and those with strong positive SPA reactions were kept for further evaluation. Necropsies were performed on selected house finches and individuals of 11 other passerine species, and samples were collected for MG testing by culture, polymerase chain reaction (PCR), hemagglutination inhibition, and histopathology. Testing revealed 19.1% of 671 birds caught at farms and 11.6% of 387 birds caught at feeder sites were SPA positive for MG. Three house finches captured on farms were positive for MG by culture and PCR, whereas three from feeder sites were positive only by PCR. No MG isolates were made from tufted titmice (Baeolophus bicolor), but 40% were positive by PCR. Individuals from 10 additional species were SPA positive only. Results suggest that MG persists at low levels in house finches in northeast Georgia and that tufted titmice may be nonclinical carriers of MG or a related mycoplasma. Positive SPA reactions in other species may be caused by nonspecific reactions or contact exposure. Current biosecurity recommendations should be sufficient to minimize risks of transmission between wild and domestic birds.  相似文献   

13.
An outbreak of Salmonella typhimurium infection in cats and humans in Sweden in 1999, associated with wild birds, is described. In the county of Värmland, 62 sick cats were examined. All were anorectic and lethargic, 57 per cent had vomiting and 31 per cent had diarrhoea. It was considered likely that salmonellosis was transmitted from cats to humans, but there were only a few such cases.  相似文献   

14.
This investigation assessed the ability of the zoonotic A/chicken/Hong Kong/220/97 (chicken/Hong Kong) (H5N1) highly pathogenic avian influenza virus to infect and cause disease in zebra finches (Taeniopygia guttata), house finches (Carpodacus mexicanus), house sparrows (Passer domesticus), European starlings (Sternus vulgaris), and budgerigars (Melopsittacus undulatus) after intranasal administration. Zebra finches were the most severely affected of the five species, demonstrating anorexia, depression, and 100% mortality within 5 days of inoculation. Gross lesions in this species were absent or only mild. But histologic lesions and the corresponding viral antigen were observed in multiple organs, especially in the nasal cavity, brain, pancreas, spleen, adrenal glands, and ovary. Significant morbidity and mortality also were observed in both house finches and budgerigars. Affected birds of these two species demonstrated anorexia, depression, and neurologic signs and typically were moribund or dead within 2 days of the onset of clinical signs. Gross lesions were mild or absent in house finches and budgerigars. Histologically, the brain and pancreas were the most consistently and severely affected organs in house finches. The brain was the most affected organ in budgerigars. Unlike these three species, house sparrows suffered only mild transient depression, had no mortality, and lacked gross lesions. Viral antigen and microscopic lesions were observed only in the heart and testicle of a minority of birds of this species. Starlings demonstrated neither clinical disease nor mortality and lacked gross and histologic lesions. Viral antigen was not observed in any of the collected tissues from starlings. These results indicate that there is significant variation in the pathogenicity of the chicken/Hong Kong virus for different species of birds, including species within the same order. In addition, neurotropism is a recurrent feature among birds that eventually succumb to infection.  相似文献   

15.
The epidemiology of subclinical salmonellosis in wild birds in a region of high Salmonella prevalence in pigs was studied. Three hundred and seventy‐nine faecal samples from 921 birds trapped in 31 locations nearby pig premises, and 431 samples from 581 birds of 10 natural settings far from pig farms were analysed for the presence of Salmonella spp. Positive samples were serotyped and analysed for antimicrobial resistance (AR). Phage typing and pulsed‐field gel electrophoresis (PFGE) on Salmonella Typhimurium isolates were also carried out. The overall proportion of Salmonella‐positive samples was 1.85% (95% CI = 0.93, 2.77). Salmonella isolation was positively associated with samples collected from birds in the proximity of a pig operation (OR = 16.5; 95% CI = 5.17, 52.65), and from non‐migratory (or short‐distance migration) birds (OR = 7.6; 95% CI = 1.20, 48.04) and negatively related to mostly granivorous birds (OR = 0.4; 95% CI = 0.15, 1.13). Salmonella Typhimurium was the most prevalent serotype and four different XbaI PFGE patterns were observed that matched the four phage types identified (U310, U311, DT164 and DT56). Only 20% of the strains showed multi‐AR. In three farms, a high degree of homogeneity among isolates from different birds was observed. These findings suggested that pig farms may act as amplifiers of this infection among wild birds, and the degree of bird density may have much to do on this transmission. Some of the Salmonella serotypes isolated from bird faeces were of potential zoonotic transmission and associated with AR. Monitoring salmonellosis in wild bird is advised.  相似文献   

16.
The prevalence of Salmonella serovars and their antimicrobial resistance patterns were investigated among Danish turkeys between 1995 and 2000, by sampling the flocks approximately 14 days before they were slaughtered. Within the flocks, the prevalence of salmonella varied from 7.1 per cent to 25 per cent, and 24 different serovars were detected. The five most prevalent, which accounted for 58.5 per cent of the isolates were Salmonella Heidelberg (16.2 per cent of the isolates), Salmonella Agona (15.8 per cent), Salmonella Derby (12.4 per cent), Salmonella Muenster (7.3 per cent) and Salmonella Anatum (6.8 per cent). In addition, a few rough isolates and isolates belonging to the antigenically incomplete formulae 6,7:-:- and 4,12:b:- were found. The level of antimicrobial resistance was low; the highest resistance was recorded to ampicillin (13.7 per cent) and streptomycin (9.0 per cent) followed by tetracycline (8.5 per cent), sulphonamides (7.7 per cent) and spectinomycin (4.7 per cent). Resistance to quinolones was very low: four isolates were resistant to nalidixic acid, and only one was resistant to enrofloxacin. No resistance was recorded to colistin, apramycin, ceftiofur, florfenicol, or amoxycillin with clavulanic acid. Only 24 isolates were resistant to two or more compounds in various combinations of up to six compounds; one Salmonella Havana isolate was resistant to six compounds. Six isolates were serovar Typhimurium, but none of them belonged to phage type DT104.  相似文献   

17.
During an epornitic of velogenic viscerotropic Newcastle disease (VVND) in southern California, free-flying wild birds, captive and free-ranging semidomestic birds, and exotic birds were collected from the quarantine area to determine their role in the epizootiology of the disease. The VVND virus was isolated from 0.04% of 9,446 free-flying wild birds, 0.76% of 4,367 semidomestic birds, and 1.01% of 3,780 exotic birds examined. Three house sparrows and 1 crow directly associated with infected poultry flocks were the only free-flying wild birds from which VVND virus was isolated. Among semidomestic species, ducks, quail, chukars, pheasants, peafowl, pigeons, and doves were found to be infected. Psttacines, pittas, and toucans accounted for 92% of the VVND virus isolations from exotic birds. In addition, domestic Newcastle disease virus (NDV) was isolated from 0.29% of the free-flying wild birds, from 1.65% of the semidomestic birds, and from 0.19% of the exotic birds collected. Hemagglutination-inhibition against domestic NDV was demonstrated in 0.24% of 3,796 wild bird serums, 8.28% of 2,004 semidomestic bird serums, and 3.90% of 231 exotic bird serums tested. Although few free-flying wild birds were infected with VVND virus in this epornitic, the isolation of domestic NDV strains from free-flying wild ducks and mourning doves suggests the potential for transportation of NDV over long distances by migratory birds.  相似文献   

18.
Samples collected from 791 wild animals (Canada geese, roe deer, hares, moose, wild boar and gulls) shot during hunting were examined for verocytotoxin-producing Escherichia coli (VTEC) O157, and thermophilic Campylobacter and Salmonella species. With the exception of one positive isolate from a wild boar, VTEC O157 was not isolated from any of the animals. Salmonella species were isolated only from the gulls, of which 4 per cent were estimated to be positive. Thermophilic Campylobacter species were commonly isolated from all the species except deer.  相似文献   

19.
Coagulase-positive staphylococci were found in the throats of 46 rooks (69 per cent) and 47 gulls (21 per cent) out of totals of 67 and 229 birds, respectively. Of 111 strains isolated from throat swabs 86 (77.5 per cent) were classified as Staphylococcus aureus and 25 strains (22.5 per cent) as Staphylococcus intermedius. Of the S aureus strains 82 per cent from rooks and 50 per cent from gulls were biotyped. Most of them were identified as biotypes D and B, only a few as biotype A, and none as biotype C. Moreover, among the 24 S intermedius strains (96 per cent) biotypes 1 and 2 could be differentiated according to the type of growth on crystal violet agar and their ability to produce acetoin and acid from maltose, mannitol and trehalose.  相似文献   

20.
The purpose of this study was to develop a multiplex polymerase chain reaction (PCR) protocol useful in the virulence genotyping of Salmonella spp. with the idea that genotyping could augment current Salmonella characterization and typing methods. Seventeen genes associated with Salmonella invasion, fimbrial production, toxin production, iron transport, and intramacrophage survival were targeted by three PCR reactions. Most of these genes are required for full Salmonella virulence in a murine model, and many are also located on Salmonella pathogenicity islands (PAIs) and are associated with type III secretion systems (TTSSs). Once the success of procedures that used positive and negative control strains was verified, the genotypes of 78 Salmonella isolates incriminated in avian salmonellosis (primarily from sick, commercially reared chickens and turkeys) and 80 Salmonella isolates from apparently healthy chickens or turkeys were compared. Eleven of the 17 genes tested (invA, orgA, prgH, tolC, spaN [invJ], sipB, sitC, pagC, msgA, spiA, and iroN) were found in all of the isolates. Another (sopB) was present in all isolates from sick birds and all but one isolate from healthy birds. The remaining five genes (lpfC, cdtB, sifA, pefA, and spvB) were found in 10%-90% of the isolates from sick birds and 3.75%-90% of the healthy birds. No significant differences in the occurrence of these genes between the two groups of isolates were detected. These results suggest that these virulence genes, and presumably the PAls and TTSSs with which they are associated, are widely distributed among Salmonella isolates of birds, regardless of whether their hosts of origin have been identified as having salmonellosis.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号