Diagnosing Clostridium perfringens infections in horses has taken a step forward, thanks to recent study results identifying two methods that extend the life of the bacteria contained in fecal samples from days to weeks.

Clostridium perfringens (type C) is a bacterium that causes severe diarrhea in horses and is one of the most common causes of neonatal diarrhea. A veterinarian makes a final diagnosis only if he or she can detect the toxin C. perfringens produces, called CPB, in diarrheic horses’ intestinal contents or feces.

"The problem is that the toxin is very sensitive to the action of trypsin and other enzymes in the intestinal contents, and CPB only persists for a limited time in the intestinal contents, like fecal matter, collected from horses," explains Francisco Uzal, DVM, PhD, a professor of clinical diagnostic pathology at the University of California, Davis, California Animal Health and Food Safety Laboratory System, in San Bernardino. This means that by the time the sample arrives at the lab, the CPB could have already degraded to the point of being undetectable, thus eliminating the chance of a positive diagnosis.

Because a firm diagnosis in diarrheic horses is important to instituting proper treatment and infection control/prevention techniques, Uzal and colleagues studied equine fecal samples "spiked" with CPB to determine how temperature and trypsin inhibitors impacted CPB detection