Porcine Clostridium perfringens type A spores, enterotoxin and antibody to enterotoxin

Forty-two Clostridium perfringens type A strains isolated from cases of diarrhoea in pigs were tested for their ability to sporulate and produce enterotoxin in three different sporulation media. Enterotoxin was produced by 11 of the 42 C perfringens type A isolates (26.2 per cent). Thirteen isolates (30.9 per cent) produced spores at a frequency of 10 per cent or more. Spore production was recorded in 24 (57.1 per cent) of the isolates. The titres of enterotoxin produced by the isolates ranged from 1:2 to 1:64. The enterotoxin produced was compared with that produced by a reference strain and found to be identical. Ninety-eight of 106 sow sera from four different farms were found to possess antibodies to C perfringens type A enterotoxin with titres ranging from 1:2 to 1:64. Spores of C perfringens type A were detected in pig faeces and intestinal contents in 20 of 23 cases of enteritis at levels of up to 5 x 10(6) cells/g of faeces. Smaller numbers of spores, up to 2 x 10(4)/g were present in five of 10 samples from non-diarrhoeic pigs. Enterotoxin was demonstrated by Vero cell assay in five of the 23 samples from diarrhoeic pigs but in none of the 10 samples from non-diarrhoeic animals. It was clear from these studies that C perfringens type A strains in pigs could sporulate and produce enterotoxin in vitro and in vivo and that enteritis might be associated with sporulating organisms in vivo.     

Equine grass sickness: serologic evidence of association with Clostridium perfringens type A enterotoxin.

Clostridium perfringens type A enterotoxin seroneutralization was carried out on sera from 50 horses recovered from grass sickness and from 100 other horses with no record of having had the disease. Of the affected horses, 70% had seroneutralizating titers higher than 1:64, half of these being equal or higher than 1:128. More than 88% of the horses with no record of grass sickness had titers lower than 1:64. These data support the theory of association between C perfringens type A toxins and grass sickness.     

The effects of Clostridium perfringens type A enterotoxin in Shetland ponies--clinical, morphologic and clinicopathologic changes

Severe abdominal pain, classic colic signs and hemorrhagic gastro-entero-cecocolitis were induced in three conventional Shetland ponies by intravenous injection with Clostridium perfringens Type A enterotoxin. Histological examination showed marked congestion, edema and hemorrhage of the large and small intestine and sloughing of the tips of the intestinal villi. Marked vacuolar degeneration of hepatocytes with dilatation of the spaces of Disse also was found. Clinical changes consisted of severe hypoglycemia, markedly increased aspartate aminotransferase levels and leukopenia that occurred rapidly.     

Necrotizing enterocolitis and death in a goat kid associated with enterotoxin (CPE)-producing Clostridium perfringens type A

A goat kid died after being depressed for several days. No significant gross abnormalities were observed at postmortem examination, while histopathological analysis revealed diffuse necrotizing enterocolitis. Isolation of Clostridium perfringens type A secreting enterotoxin (CPE) and presence of CPE in the small intestine suggest that CPE contributed to the death of this kid.     

Clinical and antibody responses to Clostridium perfringens type A enterotoxin in experimental sheep and calves.

Clostridium perfringens type A live cultures or sonicated sporulating cells, all containing enterotoxin, were repeatedly inoculated into sheep and calves by the intraduodenal route over periods of 30 to 35 days. Serum antibody to C. perfringens enterotoxin, tested by ELISA, developed in four of seven sheep and in two of four calves. The titers ranged from 400 to 1600. The live organism introduced into the duodenum did not become established in the bacterial flora of the intestinal tract.     

A negative serological relationship between cases of grass sickness in Scotland and Clostridium perfringens type A enterotoxin

In an attempt to compare the equine grass sickness as reported in Europe with that described in the Republic of Colombia, sera from horses experiencing grass sickness in Scotland were used in neutralisation tests with Clostridium perfringens type A enterotoxin. The sera, from acute and chronic cases of the disease, failed to neutralise either crude or partially-purified enterotoxin. Neither were precipitin lines formed when the sera were treated against the toxin in immunoelectrophoresis. These results suggest that grass sickness in Europe and the equine disease in Colombia have a different aetiology.     

Enteropathogenicity of purified Clostridium perfringens enterotoxin in the pig

In an assay procedure, purified Clostridium perfringens enterotoxin induced the accumulation of fluid in the ileal loop of the axenic pig. The smallest amount of enterotoxin causing a positive response was 25 micrograms (1:32 titer by counterimmunoelectrophoresis [CIEP] ), and 100 micrograms (1:128 CIEP titer) caused a marked response. Possibly, diarrhea in pigs with 1:32 CIEP titer or more of enterotoxin in the feces may be associated with enterotoxigenic C perfringens.     

Prevalence of Clostridium perfringens enterotoxin and Clostridium difficile toxin A in feces of horses with diarrhea and colic.

OBJECTIVE: To determine prevalence of clostridial enterotoxins in feces of horses with diarrhea and colic, and to determine whether an association exists between detection of clostridial enterotoxins in feces and development of diarrhea as a complication of colic. DESIGN: Prospective case series and case-control study. ANIMALS: 174 horses with diarrhea, colic, or problems not related to the gastrointestinal tract. PROCEDURE: Horses were assigned to 1 of 4 groups: colic with diarrhea (group 1; n = 30); colic without diarrhea (group 2; 30); diarrhea without colic (group 3; 57); and control (group 4; 57). Feces were evaluated by use of ELISA to detect Clostridium perfringens enterotoxin (CPE) and C difficile toxin A (TOXA). Frequency of detection of CPE or TOXA in groups 1 and 3 was compared with that in groups 2 and 4, respectively. RESULTS: Prevalence of enteric clostridiosis in horses in group 3 was 25%. Clostridium perfringens enterotoxin was detected in 9 of 57 (16%), TOXA in 8 of 57 (14%), and both toxins in 3 of 57 (5%) fecal samples collected from these horses. Neither toxin was detected in feces of the age-matched horses in group 4. Clostridial enterotoxins were detected in feces of 7 of 60 (12%) horses with colic (groups 1 and 2), however, a significant association was not found between detection of enterotoxins in feces and development of diarrhea as a complication of colic. CONCLUSIONS AND CLINICAL RELEVANCE: Clostridia are important etiologic agents of diarrhea in horses. Additionally, changes in intestinal flora of horses with colic may allow for proliferation of clostridia and elaboration of enterotoxins regardless of whether diarrhea develops.     

Testing strains of Clostridium perfringens type A isolated from diarrhoeic piglets for the presence of the enterotoxin gene

A diarrhoeic syndrome in piglets has been linked to Clostridium perfringens type A because this organism has been isolated in large numbers from all cases. The strains isolated from these cases and strains isolated from healthy piglets were screened for the enterotoxin gene of C perfringens by DNA-hybridisation. Using two different synthetic DNA-probes, none of the strains isolated from diseased pigs was positive in this reaction, indicating that the enterotoxin of C perfringens is not involved in the syndrome.     

Identification of enterotoxigenic Clostridium perfringens type A in mixed cultures.

Three known enterotoxigenic Clostridium perfringens type A strains were mixed in various combinations with three nonenterotoxigenic strains and three lots of animal intestinal contents. They were grown as mixed cultures and tested for the presence of enterotoxin by the fluorescent antibody, reversed passive hemagglutination and immunodiffusion techniques. The fluorescent antibody and reversed passive hemagglutination tests detected enterotoxin in all 16 cultures prepared but the immunodiffusion test failed on two cultures. Attempts to reisolate the enterotoxigenic strains from the mixed cultures was successful in 12 cases when two of five isolated colonies were selected.     

Predisposing factors in enterotoxemias of camels (Camelus dromedarius) caused by Clostridium perfringens type A.

C. perfringens type A was isolated from different organs and intestines from breeding and racing camels which died from peracute and acute enterotoxemias in two separate outbreaks. Pathological changes in the digestive tract were mild in breeding camels, and severe in racing camels. A polyvalent clostridial antiserum of bovine origin given intravenously had a life-saving effect on breeding camels, but not on racing camels. In the two outbreaks, fifty percent of the breeding camels were suffering from an acute Trypanosoma evansi infection, and 25% of the racing camels had developed a salmonellosis. It is suggested that both infections played an important role as predisposing factors for the outbreak of C. perfringens enterotoxemias.