Variable protection after vaccination of broiler chickens against necrotic enteritis using supernatants of different Clostridium perfringens strains.

Necrotic enteritis is an economically important disease of chickens caused by Clostridium perfringens. Immunity to necrotic enteritis is not fully characterized yet, but previous reports indicate that immunoprotective potential is present in the secreted component of C. perfringens. This study aimed to compare the vaccine potential of the supernatants of eight chicken strains of C. perfringens differing in origin, level of alpha toxin production and presence of netB gene. The supernatant of only one strain provided full protection, while one other strain provided partial protection against a severe infection challenge. Our results indicate that the protective characteristics of the supernatants are not solely based on the presence of NetB or alpha toxin.