Clostridium difficile in horses in Australia--a preliminary study

Area of Science:

• Veterinary Microbiology
• Equine Health
• Infectious Diseases

Background:

• Clostridium difficile is an opportunistic pathogen causing gastrointestinal disease in various animal species.
• Understanding C. difficile epidemiology in horses is crucial for disease prevention and control.
• Previous studies have identified specific toxin profiles and ribotypes associated with C. difficile in horses globally.

Purpose of the Study:

• To investigate the prevalence and characteristics of Clostridium difficile in Australian horses.
• To determine the toxin profiles and ribotypes of C. difficile isolates from horses.
• To compare Australian C. difficile equine strains with those found internationally.

Main Methods:

• Faecal specimens were collected from 174 horses in Australia between 2007 and 2009.
• Samples were tested for the presence of C. difficile using culture methods.
• Isolates were characterized by PCR for toxin A, toxin B, and binary toxin, and by ribotyping.

Main Results:

• C. difficile was isolated from 14 (23%) of 62 diarrheic horses, including 10 foals; none were found in healthy horses.
• The most common toxin profile was A(+)B(+)CDT(-).
• Six different ribotypes were detected, with ribotype 012 being the most frequent. Notably, ribotype 078 was absent.

Conclusions:

• The epidemiology of C. difficile in Australian horses appears similar to international patterns, with a notable absence of the globally significant ribotype 078.
• Further surveillance is recommended to monitor potential changes in C. difficile strains and their epidemiology in Australian equine populations.
• All identified equine C. difficile isolates were susceptible to metronidazole and vancomycin, suggesting these treatments may be effective.