For heat stress

Ruminants cannot handle high temperatures because they have few sweat glands, making sweating an inefficient cooling mechanism. To cope, they primarily rely on panting and initiating a cascade of metabolic and behavioral changes designed for survival.

First, an animal under heat stress will voluntarily reduce its dry matter intake. This is a strategic response, as the process of digestion and fermentation generates a significant amount of internal heat. However, this leads to a negative energy balance, forcing the body into a state of metabolic reprogramming. It actively redirects energy and resources away from “non-essential” productive functions (such as milk synthesis, growth, and reproduction) to prioritize core survival systems. This physiological shift is compounded at the cellular level by oxidative stress, a damaging imbalance where heat-induced metabolic strain leads to an overproduction of reactive oxygen species that overwhelm the animal’s natural antioxidant defenses. The combined result is compromised cellular health, a weakened immune system, and a direct, negative impact on animal welfare and farm productivity.

Enhancing ruminant performances

The strategic use of ruminants feed additives supports internal resilience. Antioxidants such as Vitamin E, Selenium, and Beta-carotene are essential to combat oxidative stress and bolster the immune response . Electrolytes (e.g., sodium, potassium, magnesium) are crucial to maintain fluid balance, compensating for losses through sweating and increased urination. Gut health modulators like yeast, probiotics, and prebiotics improve rumen fermentation and nutrient absorption, offsetting the negative impacts of reduced feed intake. Energy supplements, such as rumen-inert fats, increase the diet’s energy density with a lower heat increment. Adjusting feeding times to cooler parts of the day also minimizes peak metabolic heat production coinciding with peak ambient temperatures.

An integrated management system, combining effective environmental cooling, optimal hydration, and targeted nutritional support, is essential for safeguarding animal welfare, preserving health, and maintaining productivity in the face of increasingly challenging thermal conditions.