Clostridium difficile from healthy food animals: optimized isolation and prevalence

Area of Science:

• Veterinary Microbiology
• Food Safety
• Bacterial Pathogenesis

Background:

• Clostridium difficile is an opportunistic pathogen.
• Food animals are potential reservoirs for C. difficile.
• Effective isolation methods are crucial for surveillance.

Purpose of the Study:

• To compare the efficacy of two C. difficile isolation methods.
• To evaluate method performance across different food animal species.
• To inform optimal diagnostic strategies for C. difficile in livestock.

Main Methods:

• Single alcohol shock (SS) and double alcohol shock (DS) isolation methods were employed.
• Selective enrichment used cycloserine-cefoxitin fructose broth with sodium taurocholate.
• Isolation was performed on tryptic soy agar with sheep blood and cycloserine-cefoxitin fructose agar.

Main Results:

• C. difficile was detected in swine (15.9%), dairy cattle (2.4%), and beef cattle (6.3%) fecal samples.
• DS method showed significantly higher recovery from swine feces compared to SS.
• SS method demonstrated significantly better recovery from beef cattle feces compared to DS.

Conclusions:

• Food animals can harbor Clostridium difficile.
• The choice of isolation method impacts C. difficile recovery rates.
• Isolation protocols require optimization based on the target animal species.