As global temperatures rise and heatwaves become more frequent, fattening livestock are increasingly exposed to heat stress. This condition can lead to reduced feed intake, poor weight gain, suppressed immune function, and even mortality. In such conditions, targeted nutritional strategies can play a key role in minimizing the harmful effects of heat and maintaining animal health and productivity (Collier et al., 2019).
One of the simplest interventions is to provide high-quality, digestible feed. Low-quality forages like straw increase rumen fermentation, which in turn generates heat (West, 2003). Adding rumen-protected fats (e.g., calcium soaps of fatty acids) at 2–5% of the diet provides extra energy with minimal heat production (Drackley et al., 2003).
Heat stress increases oxidative stress in the animal's body. Supplements like vitamin E and selenium help protect cells from damage. In one study, sheep supplemented with vitamin E and selenium showed lower body temperatures, reduced respiration rate, and improved antioxidant status (Chauhan et al., 2014).
Animals lose large amounts of sodium, potassium, and chloride through sweat and urine under heat stress. Adding electrolytes (NaCl, KCl, sodium bicarbonate) to feed or water helps maintain hydration and acid-base balance (Lara & Rostagno, 2013). These are available as powders or oral solutions.
Niacin (vitamin B3) helps expand blood vessels, increasing skin blood flow and improving heat dissipation. Research shows that adding ~800 mg/kg niacin to feed reduced body temperature and respiratory rate in beef cattle under heat stress (Zimbelman et al., 2010).
Betaine helps cells retain water and improves energy metabolism. Supplementing 15–30 g/day in dairy cows improved feed intake, rumen function, and antioxidant capacity (Sahin et al., 2011). In sheep, as little as 2 g/day of betaine reduced body temperature and improved performance.
Live yeast (e.g., Saccharomyces cerevisiae) and probiotics improve rumen function and nutrient absorption. Studies show that yeast-supplemented cattle under heat stress had 0.3°C lower rectal temperature and better productivity (Dehghan-Banadaky et al., 2013).
Several combined supplements are designed to support livestock during heat stress. Examples include:
Prody Live Cell" live yeast"
Bioactive buffer (BioActive)
Feed animals during cooler parts of the day (early morning or late evening).
Provide unlimited access to clean, cool water.
Use shade structures and fans or sprinklers to reduce heat load.
Heat stress is a major challenge in livestock production, especially in warm regions. Combining nutritional interventions with good management practices can significantly reduce its harmful effects. Farmers are encouraged to consult with animal nutritionists to select the most effective strategy based on their location, livestock species, and production goals.
References
Collier, R. J., et al. (2019). “Feed and nutritional management to reduce the impact of heat stress.” J. Dairy Sci.
West, J. W. (2003). “Effects of heat-stress on production in dairy cattle.” J. Dairy Sci.
Drackley, J. K., et al. (2003). “Feeding rumen-protected fats to dairy cattle.” Vet. Clin. North Am.
Chauhan, S. S., et al. (2014). “Antioxidants in sheep under heat stress.” Small Ruminant Res.
Lara, L. J., & Rostagno, M. H. (2013). “Impact of heat stress on livestock.” J. Anim. Sci.
Zimbelman, R. B., et al. (2010). “Niacin and heat stress in dairy cows.” J. Dairy Sci.
Sahin, K., et al. (2011). “Betaine and heat stress in ruminants.” Livestock Science
Dehghan-Banadaky, M., et al. (2013). “Live yeast and performance under heat stress.” Iranian J. Anim. Sci.
Bagath, M., et al. (2019). “Role of seaweed extracts in ruminant heat tolerance.” Animals (MDPI)