Cold Stress in Livestock: Effects on Animal Performance
As temperatures drop, livestock require more energy to maintain their body temperature, potentially affecting their health, growth and productivity. But cold weather is not the only risk factor: wind, humidity and housing conditions also influence how well animals adapt. How does cold stress affect livestock performance, and which management practices can help farmers protect their herds during winter?
How Do Livestock Respond to Cold Stress?
Understanding thermoregulation mechanisms
Livestock rely on several physiological mechanisms to maintain a relatively stable body temperature despite changes in their environment:
- Vasoconstriction: Blood vessels near the skin constrict to reduce heat loss.
- Muscle shivering: Involuntary muscle contractions generate heat.
- Increased metabolic heat production: The body uses additional energy resources to maintain its internal temperature.
In ruminants, feed fermentation in the rumen also contributes to heat production.
These mechanisms help animals adapt to low temperatures, but they come at an energy cost. When exposure to cold conditions continues, an increasing proportion of available energy is directed towards thermoregulation, potentially at the expense of growth, production or body condition.
This adaptation largely depends on the lower critical temperature, the threshold below which an animal must generate additional heat to maintain its body temperature. This threshold varies according to species, age, body condition, acclimatisation and housing conditions. For example, an adult cow accustomed to cold weather will generally cope better than a newborn calf or piglet.
Cold stress risk cannot therefore be assessed based on outdoor temperature alone. The animals’ individual sensitivity and environmental conditions must also be considered.
Why Do Wind and Moisture Make Cold Stress Worse?
A temperature of 5°C will not have the same impact on an animal kept in a dry, sheltered environment as on one exposed to rain and wind.
An animal’s coat provides natural insulation. When dry, it traps a layer of air that helps reduce heat loss. Moisture, however, reduces these insulating properties, while wind increases heat exchange with the surrounding environment.
How Does Cold Stress Affect Livestock Performance?
Increased energy requirements at the expense of production
When temperatures fall below their thermal comfort threshold, animals use more energy to maintain their body temperature. If their diet does not meet these additional requirements, they begin drawing on body reserves, potentially compromising animal performance.
In beef cattle and growing animals, a prolonged energy deficit can reduce average daily gain and impair feed efficiency.
In dairy cows, these additional energy demands may also reduce the energy available for milk production, particularly when their energy balance is already compromised. The extent of this impact depends on production levels, ration quality and housing conditions.
Greater vulnerability in young animals
Newborn animals are particularly vulnerable to low temperatures. Their high body surface area-to-weight ratio increases heat loss, while their energy reserves remain limited.
In calves, prolonged exposure to cold, especially in wet conditions, increases the risk of hypothermia. Prompt drying after birth, adequate colostrum intake and a clean, dry, sheltered environment are therefore essential to maintaining their vitality.
Potential consequences for body condition and reproduction
The effects of an energy deficit during winter may extend beyond the cold period itself.
When animals continuously draw on their body reserves, their body condition score may decline. Poor body condition can negatively affect reproductive performance, particularly in beef cows.
During late gestation, inadequate nutritional intake may compromise preparation for calving and delay the resumption of ovarian activity after giving birth.
The key is therefore to anticipate cold periods and prevent nutritional imbalances before they have a lasting impact on herd performance.
How Can Livestock Nutrition Be Adapted During Winter?
Adjusting energy intake to actual requirements
Nutrition is one of the main factors helping animals cope with cold weather. The objective is not necessarily to increase feed quantities, but rather to adapt the ration to actual nutritional requirements, while considering feed intake capacity and digestive balance.
For ruminants, several factors should guide these adjustments:
- The energy value and digestibility of available forage.
- Actual dry matter intake.
- Physiological stage and production level.
- Body condition and degree of exposure to cold.
Forage analysis helps assess nutritional quality and identify potential supplementation needs. It provides a valuable basis for adjusting energy intake without disrupting ration balance.
Maintaining digestive efficiency to improve nutrient utilisation
In ruminants, feed efficiency largely depends on proper rumen function. Rumen microorganisms break down plant fibres and ferment carbohydrates to produce volatile fatty acids, including acetate, propionate and butyrate, which are major energy sources for the animal.
During winter, when maintenance energy requirements increase, preserving digestive efficiency becomes particularly important.
Sudden dietary changes or excessive concentrate intake relative to physically effective fibre can disrupt rumen fermentation, lower ruminal pH and reduce nutrient utilisation.
Any changes to the ration should therefore be introduced gradually, allowing the rumen microbiota to adapt while maintaining consistent feed intake.
Ensuring adequate water intake and mineral balance
Nutritional efficiency also depends on sufficient water intake. During winter, frozen drinking systems or restricted access to water points can reduce water consumption and, indirectly, feed intake.
Animals must therefore have continuous access to clean drinking water, even when temperatures fall below freezing.
At the same time, a balanced supply of minerals and vitamins remains essential for normal physiological function. Calcium, magnesium, phosphorus and trace elements are involved in numerous processes, including energy metabolism, muscle function and immune defence mechanisms.
Although cold weather primarily increases maintenance energy requirements, it does not systematically increase mineral and vitamin requirements. The priority is to maintain a balanced nutritional supply suited to the animals’ physiological stage and production level.
Which Livestock Management Practices Help Reduce the Effects of Cold Weather?
Providing a dry and sheltered environment
Appropriate nutrition alone is not enough if animals remain exposed to unfavourable environmental conditions. Housing quality and protection from adverse weather are equally important in limiting heat loss.
Indoors, dry resting areas, well-maintained bedding and appropriate stocking density contribute to thermal comfort. Ventilation should also remove excess moisture and gases while preventing direct draughts on the animals.
Outdoors, hedges, windbreaks and natural or purpose-built shelters can reduce exposure to wind and precipitation.
In all situations, keeping animals dry remains a priority, as moisture significantly increases heat loss.
Monitoring the most vulnerable animals
Not all animals respond to cold weather in the same way. Newborns, older animals, those in poor body condition and animals going through demanding physiological stages require particular attention.
Farmers should watch for warning signs such as reduced feed intake, loss of body condition, persistent shivering, behavioural changes or an unusual decline in performance.
Regular monitoring helps identify these situations early and adjust management practices before their consequences become more severe.
Preparation also plays a key role. Checking drinking water systems, securing feed supplies and preparing shelters ahead of a cold spell can help farmers manage their herds more effectively.
Nutrition and Livestock Management: A Combined Approach to Maintaining Performance
Managing the challenges of winter requires a comprehensive approach combining suitable housing conditions, balanced nutrition and regular herd monitoring.
Feed efficiency is a key factor, helping animals make better use of the nutrients provided by their diet.
This approach is closely aligned with the expertise of TIMAC AGRO, which develops animal nutrition solutions designed to optimise digestive function in ruminants.
For example, the SPADEA RUMEN range helps support rumen balance by promoting microbial activity and pH stability, contributing to more efficient feed utilisation.
Combined with technical support tailored to each farm’s specific needs, these solutions help maintain animal performance throughout winter and all year round.
