Oral vaccination of broiler chickens against necrotic enteritis using a non-virulent NetB positive strain of Clostridium perfringens type A

All vaccination regimes elicited serum and mucosal antibody responses to alpha toxin and to secreted proteins of both nvNetB+ and a very virulent NetB positive (vvNetB+) strain (p < 0.0001 to p < 0.05). In some vaccinated groups, there was milder intestinal pathology upon disease challenge. 55% of birds vaccinated orally at days 2, 12 with nvNetB+ adjuvanted with CT did not develop any lesions of NE by 6 days post challenge, compared to a 100% incidence of NE lesions in the unvaccinated disease challenged group.