Should We Use Probiotics for Intestinal Disease?

Introduction
The body harbours a vast microbial population consisting of an array of commensal bacteria, viruses, fungi and parasites. This microbial population (the microbiota) outnumbers the host’s own cells by a factor of ~10 and the complex bacterial population is required for health. While the focus tends to be on acute diarrhoea, alterations in the microbiota presumably play important roles in various allergic and metabolic diseases, neoplasia and obesity, and likely a wider range of conditions. There has only been recent investigation into the equine intestinal microbiota, but remarkable complexity and diversity have been identified in healthy horses, with significant alteration in disease states (Costaet al. 2012; Steelman et al. 2012).

Use of probiotics in horses
While a plethora of probiotics is available commercially and they are used on countless horses, there is essentially no objective evidence of efficacy, or even safety, with companies focusing their efforts on marketing rather than research and quality control. [...]