Rev up your cow’s rumen to prevent SARA during heat stress


Optimize rumen function for increased cow performance and feed efficienc.

Have you ever felt like it’s too hot to eat? During periods of heat stress, cows can feel the same way. Just like humans, cows often change their feeding behavior as temperatures and humidity rise. But, while most people can skip a lunch or two without serious consequences, high-producing dairy cows shouldn’t miss a meal if you want to keep peak performance.

“When the temperature-humidity index rises, dairy cow meal frequency generally goes down, and meal size often increases,” explains veterinarian Andy Skidmore, Lallemand Animal Nutrition Technical Services – Ruminant.

“These behavioral changes can affect rumen pH and function, leaving cows vulnerable to sub acute ruminal acidosis (SARA), which cuts into ration and milk component performance,” he adds.

Adding a live yeast probiotic like S. cerevisiae CNCM I-1077 to dairy rations can help slash SARA’s influence on your herd. Here’s what you need to know:

Decrease the effects of SARA

SARA is a common condition occurring when rumen pH stays lower than 5.8[1] for a prolonged period. It’s tricky to diagnose because cows move in and out of SARA and usually do not show clinical signs of illness. But you can see the impact as depressed fiber digestion associated with SARA translates into lowered milk component production.[2]

The decreased milk components from SARA carry a noteworthy financial drain. Conservatively, it’s estimated that SARA can cost dairy farmers $1.12/day/cow.[3] That’s $1,120 every day for a 1,000-cow herd.

“SARA can occur even in well-managed herds, but it’s especially problematic in early lactation and high-producing cows,” says Skidmore. “It’s characterized by daily episodes of low ruminal pH that last several hours. The remedy to overcoming SARA is to reduce the time cows spend in these low rumen pH conditions.”

Data-driven results

More than 20 years of research shows adding the live yeast probiotic S. cerevisiae CNCM I-1077 to rations helps improve cow performance reducing SARA incidence, even during heat stress.[4] For instance, animals fed rations without the live yeast probiotic S. cerevisiae CNCM I-1077 spent more than double the time under SARA conditions (240 minutes versus 78 minutes per day) than those receiving rations including S. cerevisiae CNCM I-1077.[5]

That’s because this feed additive helps increase fiber digestibility and improve rumen function, which enhances rumen pH and microbial activity.

In turn, these improvements increase diet utilization to boost milk component production and cow productivity. In fact, S. cerevisiae CNCM I-1077 has been shown to improve milk components by 0.36 pounds and feed efficiency by 7.6%, even during severe heat stress.[4]

“Rumen-specific probiotics like S. cerevisiae CNCM I-1077 help stabilize rumen pH and fermentation, influencing meal patterns as a secondary effect,” says Skidmore. “Cows feel more apt to eat and production benefits are seen from the more consistent fermentation pattern, improved fiber digestibility and a quicker return to the feed bunk.”

Additionally, cows supplemented with S. cerevisiae CNCM I-1077 modified their feeding behavior to more favorable patterns.[6] Instead of fewer, larger meals which are common during heat stress, the pattern for supplemented cows included more frequent meals that tended to be smaller and occur more closely together, making for more consistent total dry matter intake levels.

Cows supplemented with S. cerevisiae CNCM I-1077 also tended to ruminate longer and have fewer periods of elevated rumen temperature.[4]

Optimize herd productivity

Along with the adoption of heat abatement strategies, adding S. cerevisiae CNCM I-1077 to rations, frequently pushing up feed and delivering feed during cooler times of the day work together to maintain feed intake and mitigate the effects of SARA in your herd.

“All of this means dairies can protect their herd against summer production losses, and the time and effort spent to carefully formulate and deliver rations pay off,” Skidmore concludes.

Rev up your cow’s rumen with rations formulated with a live yeast probiotic to help protect against SARA during heat stress. To learn more visit

Lallemand Animal Nutrition is committed to optimizing animal performance and well-being with specific natural microbial product and service solutions. Using sound science, proven results and knowledge, Lallemand Animal Nutrition develops, produces and markets high-value yeast and bacteria products ─ including probiotics, silage inoculants and yeast derivatives. Lallemand offers a higher level of expertise, leadership and industry commitment with long-term and profitable solutions to move our partners Forward. Lallemand Animal Nutrition is Specific for your success.

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