CPA1 and infection: For Clostridium perfringens type A (CpA) increased growth and adhesion in the presence of C. suis could be demonstrated in experimental infections with C. suis, and anticoccidial treatment with toltrazuril also prevented CpA overgrowth and CpA-induced necrotic enteritis (Mengel et al., 2012), indicating a synergistic relationship between C. suis and CpA. On the other hand, probiotic bacteria had no appreciable influence on the course of C. suis infection despite a beneficial effect in healthy piglets (Unterweger et al., 2018).