The effect of supplementing pony diets with yeast on 2. The faecal microbiome.

The study explores the impact of adding a yeast product (VistaEQ) to the diets of ponies to affect the populations of microbes in their digestive systems, focused on the health and welfare of high-performance horses fed energy-dense diets. The findings indicate that this yeast supplementation positively alters the digestive bacteria in horses and could be used to prevent acidosis and increase fibre digestibility.

Study Background and Objective

• The study is primarily concerned with finding effective feeding strategies for high-performance horses that consume energy-dense diets. There’s a need to find solutions to counter the harmful side effects of concentrate feeding in such horses.
• The study’s objective was to examine the influence of adding a product called VistaEQ to horse diets. This product contains 4% live yeast Saccharomyces cerevisiae and was given at a rate of 2 grams per pony per day. The researchers aimed to observe how this feeding change affects the horses’ faecal microbial populations.

Methodology and Analysis

• The study involved eight Welsh section A pony geldings in a 4-period × 8 animal crossover design. Over four separate treatments, the horses underwent a 19-day experimental period, which included 18 days for adaption and a single day for data collection. Each experimental period was then followed by a seven-day “wash-out” period.
• The scientists extracted DNA from the pony’s faeces for analysis. To assess the microbial diversity, the genetic material underwent Illumina’s next-generation sequencing, specifically focusing on the V3-V4 regions of the 16S ribosomal RNA gene.
• The microbiome α-diversity was evaluated using the 16S metagenomics pipeline in Quantitative Insights Into Microbial Ecology (QIIME™) and Galaxy/Hutlab. Significant differences between the experimental groups were identified when the linear discriminant analysis score was greater than 2, corresponding to a statistical significance of P < 0.05.

Results and Conclusions

• The study found that supplementation with S. cerevisiae yeast led to positive changes in the horse’s microbiota when added to a high-fiber diet. Both the relative abundance (RA) of the Lachnospiraceae and Dehalobacteriaceae family members associated with a healthy core microbiome increased.
• Yeast supplementation also resulted in an increased RA of fibrolytic bacteria (Ruminococcus) when a high-fiber diet was given and a reduced RA of lactate-producing bacteria (Streptococcus) when a high-starch diet was provided.
• Furthermore, yeast raised the RA of acetic, succinic acid producing bacterial family (Succinivibrionaceae) and butyrate producing bacterial genus (Roseburia) when fed with high-starch and high-fibre diets, respectively.
• These changes suggest that adding VistaEQ to the diets of horses could prevent acidosis and increase the digestibility of fiber. This could help meet the energy requirements of high-performance horses while also maintaining gut health.