Clostridia are Gram-positive anaerobic, spore-forming rods, found in soil, water as well as          gastro-intestinal tract of human and animals worldwide. Clostridial infections are among the most prevalent diseases in Iran. Clostridium causes botulism, tetanus, food poisoning, wound infections, enterotoxaemia, gas gangrene, necrotic enteritis, pseudomembranous colitis, blackleg and black disease. Clostridium also causes several diseases affecting the livestock and poultry industries throughout the world. Vaccination against clostridial infection is effective in immunization of domestic animals and birds. This review discusses clostridial infection and the development of vaccines against their infection in Iran. The last reported outbreaks of blackleg, black disease and enterotoxaemia occurred years ago, so these vaccines have been produced since the 1960s using traditional and conventional methods. In recent years, molecular biology methods have been developed and applied to the identification of clostridial diseases among animals. In this study, molecular cloning strategies for the major toxins of Clostridium species, for development of recombinant vaccines, were designed and evaluated. In vivo studies indicate that the recombinant vaccines will increase immunity against disease in laboratory animals. These experimental vaccines can thus be used in future pilot studies in Iran. This review article presents current knowledge regarding C. perfringens, C. novyi, C. septicum and C. chauvoei in the veterinary industry in Iran.

Background: Foot and mouth disease (FMD) and enterotoxaemia are serious livestock diseases. The livestock industry has suffered heavy economic losses, especially in developing countries. Objectives: These two diseases can be effectively controlled and prevented via vaccination. To prepare multivalent vaccines, Clostridium perfringens (B, C, and D) toxoids were mixed with foot and mouth disease virus (FMDV; type O) along with adjuvants aluminum hydroxide and Montanide ISA206. Methods: According to the guidelines of the World Organization for Animal Health (OIE) and pharmacopeia, sheep were the target animals. Following the injection of vaccines, ELISA and virus neutralization test (VNT) antibody titers determined the effectiveness of the test vaccines. Results: The combination vaccine with ISA206 adjuvant resulted in anti-enterotoxaemia and anti-FMD antibody titers higher than OIE values and pharmacopeia standards. A statistically significant difference was found between the combination vaccine groups with and without Montanide ISA206 adjuvant for anti-enterotoxaemia antibody titers after the second vaccination (P < 0.05). In contrast, the mean VNT antibody titer of the combined vaccine against serotype O with ISA206 adjuvant was significantly higher than that of other FMD vaccine groups (P < 0.05). Moreover, all vaccinated groups (A, B, C, D, E, Fand G) displayed significantly higher than the negative control group (P < 0.05). Conclusions: This study showed that enterotoxaemia-FMD combined vaccines could replace traditional livestock vaccines on an industrial scale.

Clostridium septicum is the causative agent of the acute fetal disease braxy and gas gangrene with major economic losses in the dairy industry. Accurate and rapid detection is great importance in this regard. Vaccination is an effective process for protection against C. septicum infection. It is necessary to identify and evaluate toxigenic Iranian isolates to produce a vaccine. This study aimed to detect Iranian isolates and evaluate toxigenic isolates as candidates for vaccine production. To this end, a total of 17 samples of animals, clinically suspected to braxy and malignant edema, were obtained. All samples were then cultured on media and microbiological and biochemical tests were performed on the colonies. The test results were confirmed by PCR amplification of the alpha-toxin gene. The toxigenic isolates were then evaluated using MLD. The experimental vaccine was produced and evaluated according to the British Pharmacopoeia Standard. According to the results, out of 17 samples, 15 samples were considered C. septicum. All samples were confirmed by PCR amplification. The most toxigenic isolate was used for experimental vaccine production. The result was successful. The Iranian isolate could be, therefore, used for vaccine production although further studies should be conducted in this regard.