Disease associated with type A strains of Clostridium perfringens is a milder condition than disease associated with C perfringens type C Clostridium perfringens Type C Enteritis in Pigs Infection of the small intestine by type C strains of Clostridium perfringens causes a highly fatal, necrohemorrhagic enteritis. It most commonly affects piglets 1–5 days old; however... read more . Diagnosis is challenging, because C perfringens type A is part of the normal intestinal microbiota, there are no consistent microscopic lesions, and disease has not been consistently reproduced experimentally. However, many swine practitioners are confident about the role of C perfringens as a cause of diarrhea in suckling pigs. Affected piglets typically have a creamy to watery, yellowish diarrhea that is self-limiting within ~5 days. Piglets' growth rates are suppressed; however, there is little to no mortality. Lesions at postmortem examination are mild and generally nonspecific; they include flaccid, thin-walled intestines with variable gas distention. No specific criteria are available to confirm a diagnosis of C perfringens enteritis in swine, given the microorganism's ubiquity in the microbiota. Diagnosis is often by exclusion of other causes of neonatal diarrhea and by isolation and identification of large numbers of C perfringens from affected segments of jejunum or ileum.