Cytotoxin CctA, a major virulence factor of Clostridium chauvoei conferring protective immunity against myonecrosis

► CctA is a new toxin of Clostridium chauvoei belonging to the β-barrel pore forming toxins. ► Antibodies against rCctA fully neutralize cytotoxic and haemolytic activity of C. chauvoei ► Vaccination of guinea pigs with recombinant CctA induces protection against myonecrosis. ► Data show that CctA is the major toxin and main virulence factor of C. chauvoei.