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1.
Thirty-four Holstein cows died after exposure to Clostridium botulinum type D toxin, presumably from contaminated haylage. The presence of type D toxin in ruminal contents was confirmed by mouse inoculation. This is the first confirmation by direct toxin isolation of C. botulinum type D toxin in cattle in North America.  相似文献   

2.
Scanning surveillance by the Veterinary Laboratories Agency revealed the emergence of suspected botulism in ruminants in 2003, presented as flaccid paralysis. From 2003 to 2009, 168 cattle and 19 sheep incidents were recorded, with mortality between 5 and 80 per cent. All sheep incidents and 95 per cent of cattle incidents had proximity to broiler litter. From July 2006, the gut contents collected from 74 affected cattle and 10 affected sheep were tested for Clostridium botulinum toxins using mice bioassays and for organisms by culture. Type D toxin was identified in 32 per cent of cattle and 18 per cent of sheep samples. C botulinum type D organisms were identified in 40 per cent of cattle and 30 per cent of sheep samples, but broth from one sample reacted with C and D antisera. Type C botulism has previously been reported more commonly than type D in the UK and has been associated with the use of poultry litter as fertiliser, bedding or feed. The almost exclusive association with C botulinum type D toxins or organisms in the gut contents in this survey suggests a change in the source or epidemiology of botulism in the UK. The source of C botulinum type D was uncertain. Broilers may carry C botulinum type D in their gut flora subclinically. The emergence of a new type D strain, or changes in broiler husbandry and nutrition, medication and other enteric infections may have affected colonisation with C botulinum. Further investigation of poultry and farm environments for sources of type D awaits the development of tests for C botulinum toxins that do not require the use of mice.  相似文献   

3.
In this study, the clinical findings and results of haematological and biochemical analyses of 26 cattle with botulism were evaluated. The most important clinical signs in the affected cattle included: decreased appetite, ataxia, difficulty to rise, loss of tongue tone, salivation and bradycardia. A definitive diagnosis of botulism was based on demonstration of the preformed toxin in ruminal and intestinal contents and feed materials including poultry litter, by mouse inoculation test. This study is the first confirmation, by direct toxin isolation, of Clostridium botulinum type C and Clostridium botulinum type D in cattle, in Turkey.  相似文献   

4.
OBJECTIVE: To compare the ability of a new single-dose botulinum vaccine containing a non-mineral oil adjuvant with a single dose of a conventional botulinum vaccine product to produce antibody to Clostridium botulinum types C and D in cattle in Northern Australia. DESIGN AND PROCEDURE: One hundred and fifty Brahman steer weaners were randomly divided into two groups receiving either a single dose of CSL Bivalent Botulinum vaccine or Websters Singvac. Blood samples were collected at 0, 8 and 24 weeks and tested by antibody ELISA. The final samples were also tested by the toxin neutralisation test, to test titres of neutralising antibody. RESULTS: Six months after inoculation, cattle vaccinated with Websters Singvac had ELISA antibody response twice that of CSL conventional product. However, this difference was only evident for neutralising antibody to type C botulinum toxin. Both products produced similar titres of type D neutralising antibody after a single dose. CONCLUSION: Websters' Singvac produces a greater neutralising antibody response to type C botulism upon single inoculation than a conventional vaccine. The product produces an equivalent neutralising antibody response to type D.  相似文献   

5.
Fecal samples of cattle and swine and samples of raw material and pulverized dehydrated meat taken from three rendering plants were investigated with special enrichment methods on the presence of Clostridium botulinum to get a view about the hygienic risk by the incidence of C. botulinum in rendering plants. Eight-six specimens were examined: 25 fecal specimens each of swine and cattle, 11 of raw material and 25 of pulverized dehydrated meat of three rendering plants. Twelve specimens contained C. botulinum: 7 fecal specimens, 6 of swine and one of cattle, 4 raw material specimens and one of pulverized dehydrated meat. C. botulinum was detected by its toxin production in culture medium. Six times C. botulinum type E, twice C. botulinum type B and one time C. botulinum type C was identified. C. botulinum could not be typed in other cases because the toxin quantities were too small. C. botulinum type E was detected in raw material and pulverized dehydrated meat in one of the three examined rendering plants.  相似文献   

6.
The development of specific enzyme-linked immunosorbent assays (ELISA) for antibody to types C and D Clostridium botulinum toxins for investigation of botulism in cattle is described. Partially purified type C and D toxins were used as antigens to develop these ELISAs. Specificity of the ELISAs was evaluated on sera from 333 adult beef and dairy cattle from areas with no history or evidence of botulism in animals or water birds. The test was also evaluated on sera from 41 herds that included herds vaccinated against botulism, confirmed botulism cases and herds from areas where the disease is considered endemic. The ELISAs detected the presence of antibody to botulinum toxins in samples from vaccinated cattle and both convalescent and clinically normal animals from unvaccinated herds with outbreaks of botulism. Antibody was also found in unvaccinated animals from herds in which there had been no diagnosed botulism cases in areas where botulism was considered endemic. Sera from some unvaccinated cattle with high ELISA reactivity was shown to be protective for mice in botulinum toxin neutralisation tests. The use of these tests in investigations of botulism in cattle is discussed.  相似文献   

7.
Serology has been used to diagnose retrospectively types C and D outbreaks of botulism in cattle in Australia and this study has investigated whether the approach would be applicable in England and Wales. Three hundred sera from routine surveillance submissions in England and Wales were used as a negative control population. Some stored sera were available from a small number of clinical cases of botulism and 125 samples were collected from cohort groups of clinical cases in four new outbreaks of botulism. Three of these outbreaks were identified as being caused by type D Clostridium botulinum toxin. Sera were tested by antibody ELISA in laboratories in Australia and Germany. There was no increase in the proportion of animals seropositive to type C or D antibody in the botulism-associated cattle. The proportion of samples which were seropositive to type D antibodies was <2% in both the negative control and outbreak populations. It was concluded that single time serology is unlikely to be helpful for retrospective diagnosis of outbreaks of type D botulism in England and Wales.  相似文献   

8.
Because of the difficulty in identifying botulinum toxin in cattle, it is hypothesized that cattle are sensitive to levels of toxin below the detection limits of current diagnostic techniques (the mouse protection bioassay and the immunostick enzyme-linked immunosorbent assay [ELISA] for type C botulinum toxin). Using an up-down method for toxicologic testing, the median toxic dose (MTD50) for cattle was determined. Four lactating Holstein cows were dosed at 0.125 or 0.25 ng/kg with Clostridium botulinum type C toxin and failed to develop clinical signs of botulism during the 7-day observation period. Three cows given 0.50 ng/kg of toxin developed clinical signs of botulism. From these results, the MTD50 was calculated at 0.388 ng/kg (3.88 mouse lethal doses/kg) using the trim-logit method. These results suggest that cattle are 12.88 times more sensitive to type C botulinum toxin than a mouse on a per kilogram weight basis. The mouse protection bioassay and the immunostick ELISA for type C botulinum toxin failed to identify the presence of the toxin in the serum, blood, and milk samples taken from all 7 animals.  相似文献   

9.
The present investigation was carried out in order to find a suitable medium for the production of proteolytic enzymes from different types of Clostridium botulinum. Proteolytic activity was found in Clostridium botulinum types A, B, C, D and F, while supernatants of Clostridium botulinum type E did not possess any proteolytic activity at all.Skim milk medium possessed the greatest ability for the production of proteolytic enzymes from the different cultures of Clostridium botulinum tested, while Robertson’s meat broth produced lowest amounts. Highest titres were usually found after 4–5 days of incubation and, after this period, the level of proteolytic activity decreased.  相似文献   

10.
By the use of the electrophoretic casein precipitating inhibition test (CPI-test) the serological relationship between proteolytic enzymes produced by different species within the genera Clostridium and Bacillus has been tested. The proteases produced by Clostridium botulinum types A, B, C, D and F cross-reacted with each other. Clostridium botulinum strain 84 was inhibited by antiproteases produced against Clostridium sporogenes, Clostridium botulinum types C and F (protease F I and F II), but not by antiproteases against Clostridium botulinum types B and F (protease II), Clostridium bifermentans and Clostridium perfringens. The protease of the newly described Clostridium botulinum strain 89 (type G) was inhibited by Clostridium sporogenes antiprotease, but not by any of the other antiproteases. It is not possible to differentiate between Clostridium botulinum, Clostridium sporogenes and Clostridium perfringens by use of serological differentiation of their proteolytic enzymes. The protease of Clostridium bifermentans is not serologically related to any of the species tested in this investigation. Proteases produced by different Bacilli were not inhibited by antiproteases from Clostridium botulinum types B, C and F, Clostridium sporogenes, Clostridium bifermentans, and the two strains of Clostridium perfringens tested. This investigation indicates a serological relationship between proteases from different Clostridium species, but not a serological relationship between proteases produced by the Clostridium species and Bacillus species tested.  相似文献   

11.
A major outbreak of botulism in cattle being fed ensiled poultry litter   总被引:1,自引:0,他引:1  
Eighty of a group of 150 housed beef cattle showed classical signs of botulism after eating a batch of ensiled poultry litter. Sixty-eight of the animals died and Clostridium botulinum type C toxin was detected in 18 of 22 sera examined. C botulinum organisms were isolated from the ensiled litter and type C toxin was demonstrated in samples of decomposed poultry carcases present in the litter. This outbreak of bovine botulism was the most serious to have been recorded in Europe and was the first associated with feeding ensiled poultry litter.  相似文献   

12.
This study was undertaken to evaluate two monoclonal antibody-based sandwich ELISAs (sELISAs) for the detection of Clostridium botulinum neurotoxins (BoNTs) types C and D from culture-enriched intestinal content samples from cattle. To validate the diagnostic significance of the presence of cultivable, toxin-producing C botulinum in the intestines of cattle, samples from both suspect and non-suspect botulism cases were examined. BoNT was detected by both sELISAs in a greater number of suspect animals than by direct testing of uncultured samples by mouse bioassay. One sELISA detected two BoNT C and one BoNT Group III mosaic isoform in three animals that were missed by the other, and both sELISAs failed to identify samples from two mouse bioassay-positive BoNT C animals. BoNT D was also detected in one non-suspect sample by one of the sELISAs.  相似文献   

13.
Proteolytic activity has long been regarded as an important characteristic for distinguishing between different types of Clostridium botulinum. While all strains of Clostridium botulinum type A examined so far possess proteolytic activity, the types B and F have both proteolytic and non-proteolytic varieties. Clostridium botulinum types C, D and E were generally regarded as non-proteolytic, but different investigators have shown proteolytic activity in certain strains of these types. A summary of the classification of proteolytic enzymes in general is given and further, investigations are reviewed on the proteolytic activity in Clostridium botulinum.  相似文献   

14.
Clostridium botulinum toxin, type C, could be demonstrated by means of temperature induced microcomplement fixation in blood serum and in aspirated rumen fluid of cattle suffering from botulism. The results were already available after seven hours. Botulinum toxin likewise could be identified from hair of a suspicious carcass. The investigations confirm the high sensitivity of this method.  相似文献   

15.
Since a case of a veterinarian was reported, who was likely to be infected/intoxicated by Clostridium botulinum during the handling of a diseased animal, tonsils in animals were tested for botulinum neurotoxin and bacterial forms of neurotoxic Clostridium botulinum during routine botulism laboratory examinations including standard samples (intestinal tract and liver) from 48 cattle, 11 horses, and 14 goats. Ten out of 60 samples from tonsils contained free botulinum toxin, and 12 out of 59 were positive for live toxin producing bacteria. In 32 out of 162 intestinal samples toxin was detected. Toxin producing bacteria were found in 37 samples. Eight of 56 liver samples contained free toxin, and 15 out of 43 toxigenic bacteria. Samples from 10 slaughter pigs were all negative, whereas from slaughter cattle tonsils had a high incidence of toxin (7 of 10) or toxigenic bacteria (2 of 8). The results are discussed in the context of effects on animal health and botulism as zoonosis.  相似文献   

16.
A diffuse lower motor neurone paralysis developed in a 6-month-old male Australian cattle dog pup 4 days after it had eaten the carcase of a rotting duck in Centennial Park, Sydney. Two other dogs which ate smaller portions of the same carcase were less severely affected. Clostridium botulinum type C was isolated from and C. botulinum type C toxin was detected in faeces from the severely affected dog. The serum contained 25 LD50 of toxin/ml. The high C. botulinum count and toxin level in the faeces declined progressively during the ensuing weeks, but 114 days after ingesting the carcase C. botulinum type C was still present in faeces and a low toxin titre persisted. Soil, mud and water samples in the area of the duck ponds in the park contained C. botulinum type C spores. Spores and high toxin titres were also found in the intestine of the carcases of 2 birds in the area.  相似文献   

17.
Botulism was diagnosed clinically in grazing cattle on three closely sited dairy farms. The evidence suggests that the source of the toxin was poultry carcases containing types C and D Clostridium botulinum. These organism were also found in the alimentary tract of affected animals. Silage is suspected as having acted as a vehicle for the organisms and, or, toxins in cases which occurred later in housed cattle on one of the farms.  相似文献   

18.
Clostridium botulinum type B toxicosis was diagnosed as the cause of generalized weakness and death in a group of cows and mules fed from the same batch of rye silage. One severely affected cow was treated and recovered, as did other less severely affected cows. All affected mules died. The remaining cattle in the herd were then vaccinated before continued feeding of the silage.  相似文献   

19.
Botulism is an intoxication caused by ingestion of feed or water contaminated with the toxin of Clostridium botulinum. In cattle, intoxication usually results from the ingestion of feed containing preformed type C or D toxin, either in feed which has been contaminated with toxin-containing carcasses or in feed in which there has been primary multiplication of C. botulinum and toxin production. The initial signs of botulism are progressive difficulty in chewing and swallowing, caused by paralysis of the tongue and muscles of mastication. This results in slow prehension and chewing of feed, water and feed falling out of the mouth, excessive salivation and weakness of the tongue. After 1 to 3 days, generalised paralysis occurs followed by death due to respiratory paralysis. Intravenous fluid therapy is the recommended treatment. The administration of antiserum is of limited value in advanced stages and is used mainly as a prophylactic measure in cattle herds in which an outbreak has just started. Active immunization of cattle in high-risk herds is also an option. It is critical that cattle not be fed feed contaminated with soil or carcasses.  相似文献   

20.
Twenty-two lactating Holstein cattle in Tennessee had clinical signs of intoxication with preformed Clostridium botulinum toxin. These signs included weakness, paralysis of the tongue and chest muscles, abdominal breathing, and, in 11 of the 22 cows, death. Differential diagnoses included hypocalcemia, hypomagnesemia, carbohydrate overload, and several toxicoses including mycotoxin, lead, nitrate, organophosphate, atropine or atropine-like alkaloid, and botulism. A diagnosis of botulism by the ingestion of preformed C. botulinum type B toxin was made by eliminating these other diseases, by finding C. botulinum type B spores in 3 bales of round bale barley haylage fed to these cattle, and by isolating preformed type B toxin from 1 of the 3 bales. Confirmation of the toxin type was made by demonstrating mouse lethality by intraperitoneal injection of specimen extracts with neutralization by C. botulinum type B antitoxin. The haylage, harvested green and encased in black plastic bags to facilitate fermentation, was presumably contaminated by the botulinum toxin when fermentation failed to produce enough acid to lower the pH to 4.5, the pH below which C. botulinum growth is inhibited. Farmers and ranchers who use round hay balers to produce haylage should be alert to this potential problem.  相似文献   

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