Effect of transportation on fecal bacterial communities and fermentative activities in horses: impact of Saccharomyces cerevisiae CNCM I-1077 supplementation.

This study explores the impact of travel on horses’ gut bacteria and how supplementing their diet with a specific yeast strain – Saccharomyces cerevisiae CNCM I-1077 – may help mitigate any negative effects. Changes in blood stress markers were also tracked alongside shifts in the fecal bacterial communities.

Research Methodology

• The researchers used a controlled experiment involving four mature horses subjected to identical diet and transportation conditions. Their meal plans consisted of 60% forage and 40% concentrate, at 1.45% of their body weight based on dry matter basis. Some of the horses were complemented with the live yeast, Saccharomyces cerevisiae CNCM I-1077.
• Post a 14-day adaptation period, a 5-day experiment began a day prior to the transportation event (assigned as day -1). On day 0, all horses were transported simultaneously in a truck for two hours.
• The team gathered feces samples 4 hours after the morning meal on days -1, 0 (immediately post-transportation), and 3. These samples were analyzed to identify the primary functional bacterial groups and to measure fermentative variables.
• Using the method of temporal temperature gradient electrophoresis (TTGE), they analyzed the DNA from these samples to further understand the bacterial communities.
• At the same time frames, the researchers collected blood samples to determine white blood cell counts and concentrations of glucose and total protein. All these factors indicated the stress levels in horses.

Findings

• Regardless of their diet, all horses showed an increase in the ratio of neutrophils to lymphocytes during transportation. This is indicative of stress.
• The TTGE profiles of fecal bacteria varied before and after transportation. Horses who were fed the yeast supplement showed greater similarity in their bacterial makeup before and three days after transport compared to non-supplemented horses.
• From day 0 to 3, there was a rise in the molar percentage of propionate, along with a decrease in the total concentration of volatile fatty acids (VFA) and the ratio of acetate + butyrate to propionate, irrespective of the dietary regimen. The pH levels decreased in the control horses only.
• Fecal samples from horses fed the yeast supplement had higher concentrations of lactate-utilizing and cellulolytic bacteria on all sampling days compared to those from control horses.
• This research implies that even a two-hour transportation can disrupt the gut bacteria ecosystem in horses, potentially leading to long-term imbalance or dysbiosis in the large intestine. However, supplementing their diet with Saccharomyces cerevisiae CNCM I-1077 could help minimize the negative effects of such stressors on the gut bacteria ecosystem.