In the disease process, C. perfringens penetrates the upper jejunum between absorptive cells and releases beta toxin. Beta toxin causes necrosis of the villi and mucosa, often causing blood loss into the lumen and intestinal wall. Type C causes fatal hemorrhagic enteritis in neonatal calves in North America but has been particularly prevalent in swine worldwide. It is primarily fatal to animals 1–3 days old, whose digestive enzymes may not be sufficiently active to break down beta toxin. It has been experimentally shown that trypsin may normally break down beta toxin, and trypsin shortages in the digestive system of experimental animals have been used to induce type C disease. Vaccination of pregnant sows has proven effective at preventing the disease in piglets. Outbreaks in piglets from unvaccinated sows may be treated with oral antibiotics and antiserum. See also Clostridium perfringens alpha toxin References Bacterial toxins