Clostridium perfringens

foal in field

What is Clostridum perfringens?

Clostridium perfringens is a bacteria that causes inflammation of the small and large intestine (enterocolitis), resulting in severe abdominal pain, colic, diarrhea, and failure to nurse within the first week of life. The disease progresses rapidly and has a high mortality rate. Intensive medical care is required, but many affected foals do not survive.

The bacteria is normally found (commensal) in the equine gut and has been identified in both healthy and sick foals. Some strains of C. perfringens produce toxins, whereas others do not. The bacteria is classified into five different types (A, B, C, D, E) based on the toxins produced (alpha, beta, epsilon, iota, Beta 2-toxin). Some isolates also have the enterotoxin gene. Types A and C are the strains most often associated with disease in foals. Type A, which produces alpha toxin, is commonly found on horse farms. Type C, which produces alpha toxin and beta toxin, is less common, but is associated with higher mortality.

Foals are often exposed to the bacteria in contaminated feces, sometimes from the mare. Foals infected with C. perfringens are not contagious to other foals.

What are the clinical signs of Clostridum perfringens?

Clinical signs of C. perfringens infection include diarrhea, severe abdominal pain, colic, dehydration, lethargy, anorexia, abdominal distention, and sudden death.

How is Clostridum perfringens diagnosed?

Clostridium perfringens is diagnosed by culture of the bacteria from fecal samples. The identification of toxins, or specific genetic variants associated with toxin production, is necessary to categorize toxin-producing strains from those that do not produce toxins and may be part of the normal gut bacteria population. Tests that can identify these toxins include enzyme linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR).

How is Clostridum perfringens treated?

Foals diagnosed with C. perfringens usually require intensive medical treatment including intravenous (IV) fluids, supplemental electrolytes, antibiotics, anti-inflammatories, antitoxins, hyperimmune plasma, and other medications.

What is the prognosis for Clostridum perfringens?

The disease has a high mortality rate. Early detection and treatment is important for a positive outcome.

How can Clostridum perfringens be prevented?

Mares may be vaccinated prior to foaling to provide foals with antibodies through passive transfer. Good biosecurity and hygiene procedures are the best way to protect against C. perfringens infections. The bacterial spores are resistant to many disinfectants and can survive in the environment for extended periods. Stalls should be thoroughly cleaned and disinfected between foalings.

For more information:

UC Davis School of Veterinary Medicine PCR Laboratory

Diseases with horse to human transmission, UC Davis Center for Equine Health

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