Detection of enterotoxin A and cytotoxin B, and isolation of Clostridium difficile in piglets in Minas Gerais, Brazil

Clostridium difficile has emerged as a major cause of neonatal colitis in piglets, displacing classic bacterial pathogens. However, there is no information regarding the distribution of this microorganism in pig farms in Brazil. In the present study, the presence of toxins A/B and of C. difficile strains in stool samples from 60 diarrheic or non-diarrheic newborn piglets (one to seven days old), from 15 different farms, was studied. The presence of toxins A/B was detected by ELISA and PCR was used to identify toxin A, toxin B and binary toxin gene in each isolated strain. C. difficile A/B toxins were detected in ten samples (16.7%). Of these, seven were from diarrheic and three were from non-diarrheic piglets. C. difficile was recovered from 12 out of 60 (20%) fecal samples. Of those, three strains were non-toxigenic (A(-)B(-)) and nine were toxigenic. Of the nine toxigenic strains, four were A(+)B(+) strains and five were A(-)B(+) strains. The presence of binary toxin observed in the present study was much higher (50%) than in previously reported studies. All three non-toxigenic strains were isolated from otherwise healthy piglets. The results suggest the occurrence of neonatal diarrhea by C. difficile in farms in Brazil.