C difficile is an important emerging pathogen that causes
diarrhea primarily in neonatal swine. The agent was first
recognized as a cause of antibiotic-associated diarrhea in
humans. It most commonly causes disease in piglets 1–7 days old
and in other domestic and laboratory animals. Etiology and
Pathogenesis C difficile is an anaerobic, gram-positive,
sporeforming rod that is more oxygen-sensitive than C
perfringens. The organism can be demonstrated in the intestine
by direct Gram's stain of smears. Survival of C difficile in the
environment and shedding by carrier sows is believed to be
important in transmission. C difficile produces “large
clostridial toxins” A and B, which are thought to be involved in
lesion production. Toxin A is an enterotoxin that causes fluid
secretion into the gut lumen, and toxin B is a cytotoxin.
Affected piglets may have dyspnea, abdominal distention, and
scrotal edema. Diarrhea may not be present in all pigs affected.
Ascites, hydrothorax, and edema of the ascending colon have b