The present invention relates to a polypeptide based toxin that originates from Clostridium perfringens. The invention further relates to immunogenic compositions comprising the toxin and methods to vaccinate animals, for example chickens, such that they are less susceptible to clostridial diseases. Methods to determine whether an animal has been exposed to the toxin, polynucleotides encoding the toxin and attenuated bacteria that express a reduced or less active form of the toxin are also disclosed