Water intake and heat stress in dairy cattle

How heat stress can affect the cow’s water balance

Water is an important component of physiological processes in the body. In dairy cows, the water balance also directly influences milk production.

Under normal conditions, a dairy cow drinks an average of 130 liters of water per day. If the cow is in the first few months of lactation or produces large quantities of milk, the requirement can rise to over 150 liters per day.

In the case of heat stress, the need for water also increases, because at high ambient temperatures (temperatures as low as 16 degrees can be stressful for cows) the animal evaporates fluid through sweating and increased respiration.

If food and water intake is disrupted due to severe heat stress, this can promote dehydration. As a result, however, the rising body temperature further increases the heat stress and impairs well-being and performance. Excessive dehydration reduces blood volume and impairs oxygen distribution to the organs and the circulatory system.

In addition to a reduction in the amount of milk that the cow can produce, this often results in a reduction in milk constituents such as fat and protein content.

A negative influence of dehydration on the cycle and egg quality can also be observed. Overall, dehydration can have a negative impact on the entire immune and digestive system.

On the cow’s body, the disturbance in the water balance affects well-being, milk production, fertility and susceptibility to disease. The economic consequences are reduced milk supply and quality, rising veterinary costs and production delays.

In addition to ensuring free access to fresh water and adjusting feeding, hose ventilation can make a significant contribution to bringing the environment in the barn to an optimum level. The introduction of fresh air cools the animal efficiently and regulates the humidity.