Development and Evaluation of Clostridium perfringens Type D Toxoid Vaccines

The aim of this project was to prepare a toxoid vaccine from the prevailing pathogenic strains of Type D Clostridium perfringens strains and evaluate its immune responses in rabbits, goats and sheep. C. perfringens were isolated from enterotoxaemia suspected sheep and goats from the endemic areas of Khyber Pakhtunkhwa Province, Pakistan during 2016. The isolates were initially identified through colony characters, Gram staining and biochemical tests. The identified isolates were quantified on blood agar and confirmed through PCR. Toxins were extracted, quantified, formalized and adjuvanted with aluminium hydroxide gel. Safety, sterility and stability of the toxoid were ascertained. Bacterin toxoid of C. perfringens type D was procured from Veterinary Research Institute Peshawar. The immunogenicity of toxoid vaccines and bacterin toxoid vaccine were studied and compared initially in rabbits and then in goats and sheep. Experimental trials were conducted on 54 healthy animals of each species and were divided into three equal groups (n=18). The antibody titers were evaluated with indirect haemagglutination test. The results indicated significantly higher (P<0.05) immune titer in animal group vaccinated with toxoid vaccine prepared from pathogenic isolates and provide best protection against challenge infection.