It’s not the sexiest of topics, but the examination of manure and gut contents are providing fascinating upcoming studies for two Canadian researchers.
Dr Scott Weese and his team are looking to find out how much the ‘normal’ horses microbiota changes, over the course of a year, with a study that will collect and examine fecal samples from 15 to 20 horses.
Dr Luis Arroyo, also from Ontario Veterinary College, is setting up a simulated gut to help understand what a healthy horse microbiome looks like. Just as scientists now believe that many cases of colitis in humans are due to imbalances in the microbiome, and not pathogens as was previously thought; these findings are guiding the research into the microbiome and colitis in horses.
Both studies have received funding from Ontario Equestrian.
“The microbial communities of the gut play a crucial role in the health of the horse, and we now know there are major differences between the gut microbiota of healthy horses and those with colitis,” says Arroyo.
Both Arroyo and Weese understand the importance of researching what is ‘normal’ when it comes to the horse’s microbiota before links can be made between microbiota changes and disease. In the most recent publication of the Equine Acute Abdomen, Weese writes: “The gut microbiota plays critical roles in nutrition, metabolism, and a wide range of other functions and is absolutely required for health; however, it can also be involved with, or a direct cause of, a myriad of diseases.”
The microbial communities of the gut play a crucial role in the health of the horse, and we know now that there are major differences between the gut microbiota of healthy horses and those with colitis. In more recent years, mimicking the growth environment and nutritional conditions of the natural habitat of bacteria has revolutionized traditional bacterial culture. The bacteria populations (particularly the anaerobes) within the large colon can now be better characterized in health and disease by combining culture enriched-based methods and molecular profiling of intestinal contents of horses with or without colitis.
By analyzing samples from healthy horses over the course of a year, Weese and his team will learn if the microbiota are impacted by seasonal changes, gain insight on different diets and how they affect the microbial population and study composition versus function of microbiota. Weese proposes from horse to horse, it may be possible to have completely different bugs performing the same functions.
“When it comes to diagnosing disease, at the moment there is not enough knowledge of the equine intestinal microbiota to determine the difference between incidental or cause and effect links,” he says.
In humans there are links between endocrine disease, obesity and gut function. There is also great interest in establishing links between the gut microbiota and metabolic diseases in horses, with findings just starting to emerge. We typically think of the gut in terms of colic, laminitis and colitis but there is likely many more things equine gut microbiota can influence or be impacted by such as insulin resistance or gastrointestinal disease following antibiotic administration. The future is exciting with the possibilities of restoration of normal microbiota as a reasonable clinical goal for prevention or treatment.
But first things first for Weese means getting the scoop on poop for the baselines of ‘normal’ microbiota.