Heat Stress—How Natural Dietary Supplements Can Help

07/07/2026

Home » Heat Stress—How Natural Dietary Supplements Can Help

Summer temperatures pose a particular challenge for animals. Heat stress can set in as early as 27 °C. And even at just 25 °C, if the humidity is high, animals can quickly reach a critical condition.

The result: changes in behavior, declining performance, and in the worst case, animal deaths.

For farmers and livestock owners, it is crucial to identify risks early and take effective measures. In addition to optimized barn technology and good water management, natural feed supplements can be a valuable aid in keeping animals stable during heat stress.

In our article on heat stress, we explain the topic.

What exactly happens during heat stress?

Heat stress occurs when the body’s heat dissipation is no longer sufficient to maintain a stable body temperature.

For poultry, the risk depends not only on temperature but also on
humidity. A key parameter is the enthalpy value.
The enthalpy value is a measure of heat stress in poultry that takes into account both
temperature and humidity. It indicates the total heat content of the air
and is measured in kilojoules per kilogram (kJ/kg). This makes it a more precise
indicator than temperature alone, since poultry suffers from heat stress at
lower temperatures when humidity is high.

Protective measures are necessary when the outdoor air temperature reaches 67 kJ/kg or higher — temperatures of 72 kJ/kg can be reached inside the barn, which are life-threatening for the animals.

This value can be measured using psychrometers, hygrometers, or through automated barn climate monitoring.

Physiological Effects of Heat Stress

🌿 Reduced food intake

🌿 Lower egg production

🌿 Increased water uptake, but at the same time a loss of important minerals

🌿 Oxidative stress, which weakens the immune system

Behavioral Changes Caused by Heat Stress

🌿 Panting and breathing through the beak

🌿 Lower activity

🌿 Move to shaded or well-ventilated areas

Economic Consequences of Heat Stress

🌿 Declining production output

🌿 Quality Issues with Meat and Eggs

🌿 Increased risk of livestock losses

Feeding Strategies for Heat Stress –
Why Feed Supplements Can Help

Heat stress throws poultry metabolism out of balance: feed intake
decreases, digestion becomes less efficient, and the energy required for thermoregulation
increases.

During this phase, the animals not only need energy- and nutrient-rich rations, but also
targeted support to stabilize their vitality and performance.

Phytogenic Additives – DOSTOFARM® by Your Side

Natural feed supplements from DOSTOFARM® offer significant added value.
Our products are based on high-quality, all-natural DOSTO® oregano oil, which is monitored throughout a closed production cycle – from seed to final product. The combination of oregano and other selected essential oils promotes feed intake, supports the gastrointestinal tract, and contributes to stable digestion — all important factors for optimally utilizing nutrients from the feed.

Respiratory health is a critical concern, especially during heat waves. That’s where PHYTOsolvan® comes in: With essential oils from thyme, anise, and blue chamomile, as well as selected herbal extracts, it can help keep the respiratory tract clear and support the animals’ overall vitality.

By using DOSTOFARM® feed supplements, farmers lay the groundwork for their animals to remain more resilient even in high temperatures—all based on purely natural, EU-approved active ingredients.

Overview of Mechanisms of Action:

Oregano oil from the DOSTO® line is an effective natural supplement for heat stress:

Promotes feed intake and, consequently, nutrient intake.
Supports gut health—which is especially important because heat can weaken the gut barrier.
Antioxidant and antimicrobial properties contribute to the body’s stability.

PHYTOsolvan® products combine essential oils from thyme, anise, and blue chamomile with selected herbal extracts:

Help keep the airways clear, which improves oxygen supply.
Can have a positive impact on the animals’ well-being.

DOSTO® Liquid: Measurable Improvements in Poultry

Studies show that oregano oil, with its well-known immunostimulatory and antioxidant properties, has a positive effect on heat stress in broiler chickens.

A 2020 study by the Faculty of Veterinary Medicine at Mahanakorn University (Thailand) conducted in 2020 found that, under tropical conditions, the administration of oregano essential oil (DOSTO® Liquid) leads to positive changes in the performance, immune response, gut health, and meat quality of broiler chickens.

Greater weight gain (+62.68 g compared to the control group at 300 ppm)
Improved feed conversion (FCR 1.57 at 300 ppm)
Improved intestinal structure (higher villus-crypt ratio)
Optimized meat quality through reduced drip loss and lower TBARS values

Prevention or emergency response? It's best to start early

Natural dietary supplements should be administered before the peak of a heat cycle. Start two to three days before the expected onset of estrus.
A continuous supply of fresh, clean water.
Oregano oil to boost appetite and vitality.

Why DOSTOFARM® Products Are the Ideal Solution

With over 25 years of experience in the development and production of dietary supplements based on
essential oils, DOSTOFARM® stands for the highest quality standards thanks to controlled production chains—from seed to final product.

An exclusive contract-grown supply of oregano from the Black Sea region ensures a consistent composition. In addition, we rely on scientifically tested formulations developed in collaboration with universities and research institutions.

Our solutions, such as DOSTO® Oregano Oil and PHYTOsolvan® offer farmers practical, natural support to help them prepare as best as possible for heat waves and stabilize their herds even during acute phases.

Practical Tips for the Summer

Ensuring water quality — cool, clean, and available at all times.
Start using supplemental feed early on — not only after the animals are already suffering from the heat.
A combination of several nutrient groups — vitamins, electrolytes, phytochemicals, and probiotics.
Administer products via drinking water — ensuring rapid and reliable absorption even when feed intake is reduced.
Plan long-term feeding strategies — to strengthen the immune system before the heat sets in.

Conclusion

Heat stress is not only a matter of animal welfare, but also an economic factor. The combination of barn management, optimal water management, and natural feed supplements from DOSTOFARM® offers farmers a safe and proven way to keep their animals healthy and productive throughout the summer.