Heat Stress in Ruminants

The problem with heat stress

As temperatures climb, heat stress poses a serious challenge to ruminant health and performance. Rising temperatures, coupled with high humidity and inadequate ventilation, create an environment where animals struggle to regulate their body temperature. In response, cattle naturally alter their behavior—reducing feed intake, seeking shade, and increasing respiration. However, these coping mechanisms often come at a cost, leading to digestive disturbances, heightened inflammation, and compromised immune function. The result? Lower weight gains, reduced milk production, and overall decreased profitability.

While shade, proper ventilation, and access to clean water play a crucial role in managing heat stress, nutrition can play a key factor in supporting cattle through extreme conditions. Specific microbial solutions can help combat the negative effects of heat stress by supporting digestion, reducing inflammation, and reducing oxidative stress. By proactively addressing these challenges, you can ensure your herd remains healthy, productive, and resilient—even in the toughest climates.

How to detect heat stress in ruminants?

Our solutions

Lallemand Animal Nutrition has developed a proven, nutrition-based approach to support ruminants during challenging periods of heat stress. Since the rumen plays a central role in digestion and overall performance, any disruption caused by heat stress can have cascading effects on cattle health. High temperatures upset the balance of rumen microbiota, impairing digestion and increasing the risk of acidosis, while heating of silage further reduces feed intake. At the same time, oxidative stress rises, adding to the physiological burden on the animal. Our targeted microbial solutions are designed to support rumen function, mitigate oxidative stress, and encourage resilience, helping cattle maintain performance even in extreme conditions. Because when heat stress challenges your herd, the right solutions make all the difference.

Why choose Lallemand?

As a global leader in yeast and bacteria production, Lallemand Animal Nutrition has developed a comprehensive nutritional approach to address heat stress challenges in dairy cows, beef cattle and small ruminants. Our scientifically-backed microbial solutions enhance rumen function, boost immunity and improve overall animal performance. Supported by our expert team, we provide on-farm evaluations to identify challenges and offer tailored recommendations. With our proven results and dedicated support, Lallemand ensures your cattle stay healthy and productive, even in the most challenging conditions.

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¹³ Based on the example of 14h/day under THI >68, average THI 69, max THI 81, August in Vietnam.
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