How to manage heat stress in cattle

With rising global temperatures due to climate change, heat stress in livestock is a growing concern. Ranier van Heerden, Evonik’s business manager for ruminant solutions in sub-Saharan Africa, shared insights with Octavia Avesca Spandiel on early signs of heat stress in cattle, its physiological effects, and practical management strategies, offering valuable advice to help farmers mitigate this issue.

- Octavia Avesca Spandiel

Heat stress in livestock poses a significant challenge for farmers, especially in regions with persistently high temperatures. As climate change exacerbates these conditions, it is becoming increasingly critical for farmers to recognise, manage and mitigate the impacts of heat stress to protect their livestock and maintain productivity.

EARLY SIGNS OF HEAT STRESS

Ranier van Heerden, business manager for ruminant solutions in sub-Saharan Africa at global chemicals company Evonik, says the early detection of heat stress in livestock is pivotal in mitigating its negative effects. Changes in behaviour are often the first indicators of heat stress.

"Animals will actively seek shade, pant excessively, and salivate more than usual.

In dairy cows, a drop in DMI [dry matter intake] and [subsequently] milk production could be a clear sign," he explains.

However, some of the subtler signs of heat stress can be difficult to detect. "Conditions like subacute ruminal acidosis in dairy cows, inflammation, insulin sensitivity and/or other metabolic disturbances often go unnoticed but can severely affect performance and reproduction. In addition, low conception rates and an increase in incidences of abortions are often observed," he adds.

Environmental factors also play a key role in how heat stress manifests in different regions.

Van Heerden says coastal areas with higher humidity levels pose different challenges when compared with inland areas.

"Humidity levels significantly impact how animals cope with heat stress, as high humidity reduces the body's ability to efficiently dissipate heat through evaporation," he explains.

IMPACT ON PRODUCTIVITY AND REPRODUCTION

The physiological effects of heat stress are far-reaching and directly influence productivity and reproduction.