Evaluation the efficacy of oral immunization of broiler chickens with a recombinant Lactobacillus casei vaccine vector expressing the Carboxy-terminal fragment of α-toxin from Clostridium perfringens

Abstract

Abstract Background Clostridium perfringens (C. perfringens) is a serious anaerobic enteric pathogen causing necrotic enteritis (NE) in broiler chickens. Following the ban on antibiotics as growth promoters in animal feedstuffs, there has been a remarkable rise in occurrence of NE which resulted in considering alternative approaches, particularly vaccination. The objective of this work was to evaluate the recombinant Lactobacillus casei (L. casei) expressing the C-terminal domain of α-toxin from C. perfringens as a potential probiotic-based vaccine candidate to immunize the broiler chickens against NE. Results The broiler chickens immunized orally with recombinant vaccine strain were significantly protected against experimental NE challenge, and developed specific serum anti-α antibodies. Additionally, the immunized birds showed higher body weight gains compared with control groups during the challenge experiment. Conclusions The current study showed that oral immunization of broiler chickens with a safe probiotic-based vector vaccine expressing α-toxin from C. perfringens could provide protective immunity against NE in birds.

Keywords

• α-Toxin
• Clostridium perfringens
• Lactobacillus casei
• Necrotic enteritis
• Probiotic
• Vector vaccine