June 21 2021 08:00 AM

Sponsored content created and provided by Mark Corrigan, Ph.D., MS Biotec Director of Technical Service

There are more microbes in the rumen of a single dairy cow than humans on earth. If you think it’s challenging for all those people to work together, imagine what’s going on in the rumen.

Bacteria make up most of the vast rumen microbial population. Microbes digest feedstuffs through fermentation to create energy and protein the animal needs for maintenance and production. That’s a tall order and it hinges on pH balance in the rumen. An upset in rumen pH can send the entire digestive system off the rails, taking animal health and performance with it.

The rumen evolution

Cattle cannot survive without a fully functioning rumen; it is critical for nutrient digestion and absorption. Carbohydrates in feedstuffs are the primary energy source for ruminants and include fiber, which is digested slowly in the rumen, and starch and sugars, which are broken down rapidly.

As ruminal microbes digest carbohydrates, they produce volatile fatty acids (VFAs) — mainly propionate, acetate, and butyrate. VFAs are mostly beneficial and provide 60%–80% of an animal’s energy needs. In addition to being an energy source for production, butyrate is metabolized extensively by the epithelial cells that line the rumen, contributing to the growth of the finger-like rumen papillae that absorb nutrients.

However, there is one rumen acid that causes problems — lactate or lactic acid — and is the primary influencer of rumen pH. Under normal conditions, lactate does not accumulate in the rumen, but feeding high-grain diets to cattle that are not adapted to them can cause lactic acid build up. As an acid, lactate is ten times stronger than VFAs and significantly influences rumen pH and the health of the rumen microbial population.

If grain is rapidly introduced as a feedstuff, fast-growing bacteria may produce more lactic acid than can be utilized, reducing rumen pH. Normal fiber digestion occurs when rumen pH is between 6.8 and 6.2. As rumen pH falls below 6.2, fiber digestibility is negatively affected. As rumen pH falls below 5.5, acidosis or sub-acute acidosis (SARA) can cause animals to go “off-feed” and can lead to significant problems.

A rumen microbial boost

Cattle producers use a variety of microbial products to improve rumen health and performance, but one stands out from the crowd. Megasphaera elsdenii (or Mega e®) has a well-documented and understood mode of action. Mega e® prefers lactic acid and seeks out that energy source above all others in the rumen.

As the primary and most prolific lactic-acid utilizer in the rumen, Mega e® enables rumen pH regulation, contributes to the growth of rumen papillae, and supports the development and maintenance of a healthy rumen.

A healthy rumen microbial population is critical to health and performance. Mega e® helps bridge feeding transitions and keeps the rumen microbial team working together in the right direction.