Effect of a montmorillonite-bentonite-based product on faecal parameters of horses.

Free faecal water (fluid excreted separate from normal faeces) is a common problem of unknown origin in horses. Multifactorial causes are assumed. This study assessed the effect of a commercial product (EMP) sold to help support intestinal health of horses, particularly regarding the occurrence of free faecal water. The hypothesis was that water-binding capacity and microbial activity are improved in the large intestine of horses fed EMP. EMP contained montmorillonite-bentonite, whey and extracts from hop and absinthium. Eight adult and healthy horses kept on the same diet and bedding were additionally fed EMP. In a complete crossover study design, all horses participated as control (C) and as test animal receiving EMP (E). Faecal score was assessed. Faecal samples were analysed for pH, ammonia, dry matter content (DM), crude fibre (CF), soxhlet fat (SF), crude protein (CP), crude ash (CA), neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL) and volatile fatty acids (VFAs). None of the assessed parameters measured in the faeces showed a significant treatment effect. This study was conducted in healthy horses without any gastrointestinal disorders. VFA analysis did not show treatment effects. However, apparent higher variability in CP in the faeces of E might be a hint for changes in the intestinal microbiota. Further studies and analysis of additional parameters for example the differentiation of the faecal microbial profile in horses susceptible to free faecal water are necessary to evaluate the effect of EMP.