Ruminal Acidosis in Dairy Cows: Balancing Physically Effective Fiber with Starch Availability

The high energy diets that are typically fed to dairy cows can put the cow at risk of experiencing ruminal acidosis. High energy diets are low in neutral detergent fiber (NDF) and high in starch. The starch sources are often processed in a manner to optimize starch availability in the rumen and the fiber sources are often highly digestible and short in particle length. As a result, these types of diets are highly fermentable in the rumen and often lack the structural characteristics needed to maximize rumination time and the flow of salivary buffers into the rumen. The result is reduced pH in the rumen and increased risk of acidosis. While it is critical to meet the energy requirements of high producing cows, acidosis must be avoided to ensure high milk production and efficient use of feed.