The invention belongs to the field of
biology, and discloses swine A type
clostridium perfringens SP20 capable of secreting and expressing high-level
alpha toxin, which is preserved in the China Center for Type Culture Collection (CCTCC) with the preservation number of CCTCC NO: M 2025386. The strain has strong
pathogenicity to medium and large pigs, and can be used for establishment of a pig challenge model and
efficacy evaluation of a pig A-type
clostridium perfringens vaccine. The invention further discloses a vaccine for preventing intestinal
flatulence and
sudden death of medium and large pigs caused by the A-type
clostridium perfringens. The vaccine comprises the
alpha toxin generated by the SP20 strain. The invention fills the blank of the
disease model of intestinal
flatulence and
sudden death of middle and large pigs, and is beneficial to control of
disease infection and reduction of economic loss of breeding industry.