Spontaneous necrotic enteritis in young RFM/Ms mice.

Fatal necrotic enteritis was observed in mice 24-52 days old in the RFM/Ms breeding colony maintained in a clean conventional condition in the National Institute of Radiological Sciences. Gross lesions included hyperaemia, petechiae, erosion and the occasional formation of pseudomembranes in the mucosa of the ileum and caecum. Histologically, there was necrotic enteritis with numerous Gram-positive bacilli-forming spores but no inflammatory cell reaction. Non-type-A Clostridium perfringens was isolated from the intestinal contents. This disease cleared after the addition of chlortetracycline hydrochloride (11 mg/l) to the drinking water.

Association of iota-like toxin and Clostridium spiroforme with both spontaneous and antibiotic-associated diarrhea and colitis in rabbits.

A helically coiled, anaerobic, gram-positive sporeforming bacillus, identified as Clostridium spiroforme, was isolated from the cecal contents of all of 27 rabbits with spontaneous diarrhea, at a mean concentration of 10(6.0) spores per g of material. All of these rabbits also had a toxin present in their cecal contents that was neutralized by anti-Clostridium perfringens type E iota toxin, but not by other clostridial antitoxins. In addition, four rabbits with clindamycin-associated colitis were positive for C. spiroforme at a mean concentration of 10(4.5). All of these animals also had iota-like toxin present. Iota-like toxin was not detected in the cecal contents of 72 healthy animals, although C. spiroforme was found in two of these animals at a mean concentration of 10(6.0). C. spiroforme was shown to produce a toxin in vitro that was lethal to mice and caused dermonecrosis in guinea pigs. In all cases, this toxin was neutralized by anti-C. perfringens type E iota toxin.

[Studies of necrotizing enteritis of suckling piglets (Clostridium perfringens type C enterotoxemia) in industrialized sow breeding units. 4. Epizootiology]. / Untersuchungen zur nekrotisierenden Enteritis der Saugferkel (Clostridium-perfringens-Typ-C-Enterotoxämie) in industriemssig produzierenden Sauenzuchtanlagen.

Necrotising enteritis had been the cause of death of 4.9 per cent in 5,177 nursed piglets, which was established by pathological examination. The number of piglets, in that context, which had come from industrialised sow breeding units was equivalent to 92 per cent. The nursed piglet held the third position, next to smaller ruminants (19.4 per cent) and fowl (6.0 per cent), with regard to the occurrence of Clostridium perfringens enterotoxemia or necrotising enteritis in 112,218 animals which were pathologically examined after death. Necrotising enteritis so far has been rare in the GDR. No regional accumulation has been observed. Several outbreaks on industrialised sow breeding units actually remained stationary. The occurrence of the disease may be favoured by a number of factors which are conducive to accumulation of Clostridium perfringens Type C in a given stock. Group keeping of pregnant sows, simultaneous farrowing of larger groups of sows, group treatment of nursed piglets, using neomycin, chloramphenicol, oxytetracycline, and other antibiotics to which Clostridium perfringens is primarily resistant or has acquired resistance in the course of time are some of those contributive factors. Transmission of Clostridium perfringens Type C through feedstuff is possible, though it would lead to a real outbreak only by high intensity of the contamination, and it played a minor role in proliferation of the disease. 3479 Clostridium perfringens strains were isolated from 9,481 animals, both clinically intact and after death, with 30 species being included. Type classification revealed 2454 strains of Type A (70 per cent), 204 of Type D (5.88 per cent), 164 of Type C (four per cent), and 48 of Type B (1.34 per cent). There were 688 atoxic strains (17 per cent). Swine is the major carrier of Clostridium perfringens Type C, with 87 per cent of all Clostridium perfringens Type C strains having been isolated from swine. Swine was followed by fowl (four per cent), sheep (four per cent), cattle, rabbit, and dog (1.27 per cent each). Clostridium perfringens Type C was obtained from the faeces of clinically intact sows in seven instances, including two cases with sows (0.46 per cent) from farms with no previous record of necrotising enteritis.

[Studies of necrotizing enteritis of suckling piglets (Clostridium perfringens type C enterotoxemia) in industrialized sow breeding units. 5. Control of the disease]. / Untersuchungen zur nekrotisierenden Enteritis der Saugferkel (Clostridium-perfringens-Typ-C-Enterotoxämie) in industriemässig produzierenden Sauenzuchtanlagen. 5. Mitteilung: Bekämpfung der Krankheit.

Recent methods used and experience obtained in the control of necrotising enteritis are reported in this paper, with reference being made to both the pathogenesis and epizootiology of the disease. Two inoculations of the sows, using "Enterotoxämievakzine Dessau bivalent" five and three weeks before parturition, have worked well for prophylaxis. Oral treatment was applied to nursed piglets, using 40,000 I.U. of "Aviapen" and "V-Tablopen" penicillin per animal and day over periods between two and four days, helped to minimise piglet loss, particularly in the period between a fresh outbreak and full effectiveness of immunoprophylactic action. Such treatment was conducted metaphylactically and therapeutically. The first metaphylactic treatment was given within 24 hours from parturition. Combination of mother animal vaccination with the above therapeutic use of those two penicillin preparations worked extremely well in enzootically contaminated stocks and proved to be the most effective approach, for the time being, to controlling necrotising enteritis of nursed piglets. Yet, all those control measures failed to bring about full stock sanitation on industrialised units. Sow trading was not permitted until at least four weeks had elapsed from full effectiveness of mother animal vaccination, with the view to reducing the proliferation of Clostridium perfringens Type C via sales of breeding animals. All sows were given two "Enterotoxämievakzine Dessau bivalent" vaccinations, prior to sale. The animals were sold only to smaller farms (less than 500 sows for breeding) with concentional keeping patterns which were kept under constant diagnostic supervision. Neomycin, oxytetracycline, chloramphenicol, and other antibiotics against which Clostridium perfringens was resistant or in a position to assume resistance were used on endangered stocks only in conjunction with penicillin or not at all. This programme of control has proved to be efficient through a period of more than three years.

[Coagulation analytical studies in coli enterotoxemia in swine]. / Gerinnungsanalytische Untersuchungen bei Kolienterotoxämie der Schweine

Store pigs with spontaneous outbreaks and experimental endotoxin shock were kept under observation in the context of coagulation analysis. Heparin was applied to some of the animals to disrupt the plasmatic coagulation system. The thrombocyte count in animals with endotoxin infusion declined by some 50 to 65 percent of the original level. No statistically secured difference was found to exist between heparinised animals, on the one hand, and non-heparinised, on the other. The aggregation and adhesion of thrombocytes in all shock animals was more pronounced than that in the controls. The fibrinogen levels were lowered in both the animals with spontaneous outbreaks and the experimental animals. Thrombocyte alteration was not found to have been dependent on activation of the plasmatic coagulation system. In endotoxin shock cases activation of plasmatic coagulation proteins was found to be preceded by rise in thrombocyte aggregation.

[Experimental studies on the pathogenesis of coli enterotoxemia in swine. 3. Effect of coli enterotoxin in weaned piglets following intragastric administration]. / Experimentelle Untersuchungen zur Pathogenese der Kolienterotoxämie der Schweine. 3. Die wirkung von Kolientorotoxin bei Absatzferkeln nach intragastraler Applikation

The following results were obtained from experiments with 23 clinically intact weaned piglets, aged between five and six weeks (18 animals) or eight weeks (five animals), which had received three intragastric applications of crude enterotoxin (culture filtrate supernatant of Escherichia coli O149:K91(B)K88(L):. 1. Twelve animals (52 per cent) responded to enterotoxin application by temporary outbreaks of diarrhoea (1-8.5 hours) following differentiated latencies (2.5-10 hours). No diarrhoea was recorded from eleven piglets (48%) which had received the same doses of enterotoxin. 2. No signs of a systemic disease were clinically recordable after enterotoxin administration from 22 (96%) animals, no matter whether diarrhoea had developed or not. Respiration, temperature, heart rate, and haematological values were unchanged. Feed and water intake were normal. No exsicosis was observed. All animals exhibited lively behaviours and activity. The conclusion drawn regarding the pathogenesis of the gastrointestinal form of coli-enterotoxaemia, with reference to the authors' own earlier findings, is that in this disease parenteral endotoxin effects (following endotoxin resorption) seem to coincide with enteral enterotoxin effects.