Imagine miles and miles of beautiful, green, lush rolling pasture stretching to the horizon and surrounded by pristine white fences and glossy-coated horses grazing. It's hardly believable that the verdant grass these horses graze could lead to the debilitating disease called laminitis.
However, scientists have tied pasture-associated laminitis, or PAL, to horses' intake of nonstructural carbohydrates (sugars and starch), particularly fructans (long chains of fructose), in grasses. University of Kentucky (UK) researchers recently took some early steps toward finding a solution to this problem in a relatively common plant: hops (Humulus lupus).
When fructans reach the hindgut they cause certain strains of bacteria that produce lactic acid to proliferate, resulting in a drop in pH and a more acidic environment. Often referred to as hindgut acidosis, the pH decrease causes the intestinal cells to become more permeable, allowing bacterial metabolites to enter the bloodstream and ultimately leading to laminitis.
Similarities exist between equine hindgut acidosis and rumen acidosis in cattle. When a large amount of nonstructural carbohydrates reach the rumen, the main fermentation portion of the digestive tract, a bacterial strain known as Streptococcus bovis, produces lactic acid and decreases the rumen's pH. Researchers have also discovered that while the ionophore monensin is toxic to horses, it is highly effective in treating rumen acidosis in cattle. Ionophores draw cations, such as potassium, out of cells, ultimately preventing further bacterial growth. With this in mind, a team from UK and the USDA Agricultural Research Se