With warm weather approaching, the risk of heat stress in calves increases. Everyone is well aware that heat stress in adult cattle reduces performance, increases stress and results in increased incidence of disease, and calves are no different. Calves have an upper critical limit of 25°C, however they will start to feel the effects of heat stress at 21°C.
Signs of heat stress include panting more than 80 breaths per minute, reduced laying times and activity, with cows seeking shade. Dry Matter Intake (DMI) decreases, 68-78 DMI will drop 9.6% (Bouraoui et al) and decline in milk production.