Haemolytic patterns for presumptive identification of Clostridium perfringens type C.
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Biomedical subjects
L Niilo
Publications and source records attributed to L Niilo.
Toxigenic characteristics of Clostridium perfringens type C in enterotoxemia of domestic animals.
Eleven Clostridium perfringens type C strains isolated from fatal cases of hemorrhagic enterotoxemia of Canadian calves, a piglet, and a foal were studied for the production of soluble antigens. All the isolates from calves and a foal failed to produce delta toxin, but were capable of producing large amounts of lethal beta toxin. A strain isolated from a piglet produced delta, but very little beta toxin. Other differences were relatively minor. The results indicated that young domestic animals may be susceptible to all subtypes of C. perfringens type C. A simple method of using blood agar plates coated with type A antiserum for demonstration of hemolytic patterns was found advantageous in differentiation of C. perfringens strains.
Animals↗
Diagnostic sensitivity and specificity of an enzyme-linked immunosorbent assay for the diagnosis of Brucella ovis infection in rams.
An enzyme-linked immunosorbent assay (ELISA) for antibody to Brucella ovis was compared with a standard complement fixation test. Sera of 176 rams from uninfected flocks gave 175 negative and one suspect ELISA reaction (diagnostic specificity 99.4%) whereas the complement fixation test yielded 167 negative, seven suspect and two anticomplementary reactions (diagnostic specificity of 96.0%). Diagnostic sensitivity was evaluated on sera of 79 rams from which B. ovis had been isolated. The ELISA showed 75 positive and four suspect reactions, while complement fixation test revealed 64 positive, 13 suspect and two negative results. Considering both positive and suspect reactions, the diagnostic sensitivity was 100% for ELISA and 97.5% for complement fixation test. The ELISA method was considered more specific, more sensitive and technically more advantageous than complement fixation test as a serodiagnostic test for B. ovis infection in rams.
Animals↗
Experimental production of hemorrhagic enterotoxemia by Clostridium perfringens type C in maturing lambs.
Maturing lambs, eight to nine months old, were dosed by the intraduodenal route with various preparations of Clostridium perfringens type C. Whole cultures of this organism or cells suspended in fresh medium, both supplemented with soybean flour as a protease inhibitor, produced acute fatal hemorrhagic enterotoxemia in these animals. The latter preparation was more effective than the former in causing disease. Without the soybean supplement the inocula did not produce fatal disease. Dosing with toxic cell-free culture supernatant fluid, with or without soybean supplement, had no lethal effect. Animals that died showed severe hemorrhagic enteritis with necrosis and sloughing of the mucosal epithelium, involving jejunum, ileum and part of duodenum. These lesions were similar to those seen in natural cases of hemorrhagic enterotoxemia in neonatal animals. This experiment demonstrated that nonimmune animals are normally protected against C. perfringens type C enterotoxemia by adequate levels of pancreatic proteases in the intestine, and that factors which inhibit or reduce these enzymes predispose animals for the development of this disease.
Animals↗
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.
Animals↗
Immunoglobulin transfer and weight gains in suckled beef calves force-fed stored colostrum.
Concentrations of immunoglobulins and total proteins in second-day post-partum serum samples of 62 beef calves from multiparous dams were measured by zinc sulphate turbidity, electrophoresis, radial immunodiffusion and refractometry. These results, together with health records and weight gains, were used to evaluate the practice of routinely force-feeding 1 L of stored colostrum to suckled beef calves immediately after birth. There was no apparent benefit from such force-feeding. It did not result in greater 48-hour serum immunoglobulin levels, nor did it improve weight gains at 42 days. None of the calves required treatment for neonatal disease, but one force-fed calf died from inhalation of regurgitated colostrum.
Animals↗
An enzyme-linked immunosorbent assay for the detection of Clostridium perfringens enterotoxin antibody.
An enzyme-linked immunosorbent assay (ELISA) was adapted to test serum antibody to enterotoxin of Clostridium perfringens type A. The test was evaluated using sheep, calf and guinea pig sera and compared with passive hemagglutination and immunodiffusion tests. The ELISA was found to be more sensitive than the other two tests and was completely free from nonspecific reactions. The method was considered to be technically advantageous and suitable for semiautomated procedures.
Animals↗
Paired-image slides for effective comparative presentations.
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Some pathophysiological changes associated with infection of Eimeria zuernii in calves.
Twelve Holstein-Friesian calves were divided into two groups, one of which was infected with Eimeria zuernii. Fecal oocyst output, weight changes and various blood, cellular, protein and biochemical constituents were examined for both groups. Maximal fecal oocyst output occurred 21 days after infection. Both groups of calves gained weight in a linear fashion until day 21 postinfection when the infected group lost weight rapidly. The packed cell volume of the infected calves appeared markedly reduced. Although there was a reduction in plasma proteins it did not appear significant. There was a significant reduction in plasma Na+ and Cl- ions of the infected calves. There were no significant changes in the other blood constituents examined.
Animals↗
A survey of Clostridium perfringens enterotoxin antibody in human and animal sera in western Canada.
Sera from human, cattle, sheep, swine, and horse populations in western Canada were tested for the presence of Clostridium perfringens enterotoxin antibody by the passive hemagglutination (PHA) test, supplemented by an immunodiffusion test and by counterimmunoelectrophoresis. A total of 224 human, 345 cattle, 165 sheep, 620 swine, and 768 horse serum samples were examined. Low-titer reactions in the PHA test were detected in human, cattle, horse, and swine sera, in that order, with no titers demonstrated in sheep. The titers in human sera ranged up to 1:128 and three of these samples were also positive in the other two serological tests. The significance of this antibody is not clear, but it is suggested that the low prevalence of the antibody may reflect a low prevalence of enterotoxigenic C. perfringens strains in western Canada. Such serological surveys may be applicable to epidemiological studies involving enterotoxigenic C perfringens.
Animals↗
Clostridium perfringens in animal disease: a review of current knowledge.
The diseases caused by various types of Clostridium perfringens are critically reviewed in the light of current knowledge. Particular emphasis is placed on information concerning these diseases in Canadian livestock. There are two etiologically clearly-defined acute C. perfringens diseases recognized in Canada: hemorrhagic enteritis of the new born calf, caused by C. perfringens type C, and enterotoxemia of sheep, caused by type D. Clostridium perfringens type A may play a role as a secondary pathological agent in various disease conditions, such as necrotic enteritis of chickens. It may also cause wound infections and may provide a source for human food poisoning outbreaks. There appears to be a considerable lack of knowledge regarding the distribution of C. perfringens types, their pathogenesis, diagnosis and the incidence of diseases caused by this organism.
Animals↗
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.
Clostridium perfringens↗
Some observations on serum gammaglobulin concentrations in suckled beef calves.
Gammaglobulin concentrations were measured in serum samples collected from 23 single-suckled beef calves immediately after birth and from 346 calves at 48 +/- 12 hours postpartum. Considerable variation in these levels appeared to be associated with age and breed of dam. There were also indications that they might be influenced markedly by herd management. These post-suckling gammaglobulin concentrations were of no value in predicting incidence or severity of undifferentiated neonatal diarrhea in the beef herd as a whole, or in the individual neonate.
Animals↗
Efficacy of laboratory tests for the detection of enterotoxigenic Clostridium perfringens.
Nineteen Clostridium perfringens strains with positive erythemal and ligated intestinal loop reactions, and 22 strains with negative reactions, originating from food-poisoning cases, were tested comparatively using the fluorescent antibody (FA), reversed passive hemagglutination (RPHA), and immunodiffusion (ID) tests. All the biologically positive strains were detected by the three immunological tests used. The FA test detected five additional strains among the biologically negative group which did not react in RPHA or ID tests. Sporulating culture supernatant fluids, after 13 to 17h of growth, were satisfactory for testing for the presence of enterotoxin by the RPHA and ID tests. The FA test was used on cell smears.
Botulinum Toxins↗
Enterotoxigenic Clostridium perfringens type A isolated from intestinal contents of cattle, sheep and chickens.
One hundred and fourteen strains of Clostridium perfringens, isolated from the intestinal contents of cattle, sheep, and chickens with enteritis or other disease conditions were studied for their ability to produce enterotoxin. Reversed passive hemagglutination, fluorescent antibody and immunodiffusion tests were used. On the basis of the reversed passive hemagglutination titres, supported by the other two tests, enterotoxigenicity of the strains was arbitrarily classified into two categories: highly enterotoxigenic and potentially enterotoxigenic, with 12% falling into each category. All the highly enterotoxigenic strains originated from cases of enteritis and included all three animal species. Apart from enterotoxigenicity, one C. perfringens strain produced beta toxin (type C) and 21 strains produced large amounts of alpha-toxin. The latter strains were predominantly associated with necrotic enteritis in chickens.
Animals↗
Enterotoxin formation by Clostridium perfringens type A studied by the use of fluorescent antibody.
Fluorescein isothiocyanate-conjugated antibody to purified enterotoxin of Clostridium perfringens was used to study the intracellular formation of enterotoxin by this organism. Enterotoxin was detected at 4 h of growth at the end of the cell containing forespore. With the development of the spore, enterotoxin accumulation continued and involved the entire length of the cell until its lysis with the release of enterotoxin and mature spore. The spores did not contain demonstrable enterotoxin. Only a certain number of the sporulated cells of the enterotoxigenic strains studied produced this toxin. The amount of enterotoxin produced varied with sporulation percentage, and between strains and individual cells.
Clostridium perfringens↗
Production of bovine coccidiosis with Eimeria zuernii.
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Animals↗
The effect of enterotoxin of Clostridium welchii (perfringens) type A on fowls.
Lethal doses of enterotoxin of Clostridium welchii (perfringens) type A injected intravenously into young fowls caused immediate lassitude, with partial recovery, followed by death seven to 35 h after inoculation. Lesions found were ascites, hydropericardium, oedema of the muscles, hepatic congestion, urate deposits on the peritoneum and the pericardium, and intestinal hyperaemia. Sublethal doses produced no clinical signs or lesion. The LD50 of this enterotoxin was 74-84 mug/kg of body weight.
Animals↗