Avoid Heat Stress in Calves

Compared to Southern dairy producers, North Dakota dairy producers do not have to deal with long periods of heat, according to J.W. Schroeder, North Dakota State University Extension Service dairy specialist.

“Nonetheless, this is the time of the year when soaring summer temperatures, hot sun and high humidity can cause heat stress,” he says. “While the milking herd usually gets all the attention when it comes to managing heat stress, younger animals are affected, too. Reduced feed intake and lowered immunity, coupled with increased maintenance energy needs, can lead to poor growth and higher susceptibility to disease.”

Here are some practices to help alleviate heat stress in replacement animals:

• Protect calves from direct sunlight by placing shade cloth over hutches or moving the calves to a shaded location. If calves are housed indoors, fans may be advised.
• Space hutches to allow good air circulation between them.
• Open all vents on hutches and consider placing a block under the back wall to encourage ventilation.
• Consider using sand bedding, which will absorb body heat while calves are lying down. Since sand bedding is a poor insulator, it won’t retain the heat and calves will be cooler. As an added benefit, clean, dry sand helps control fly populations, compared with straw or sawdust.
• Allow calves to choose between being inside or outside the hutch by providing a tether or outside pen.
• Keep plenty of fresh water in front of animals 24 hours a day. Calves and heifers pant and sweat to get rid of extra body heat. If that water is not replaced, dehydration will occur and can be deadly.
• Provide shade for older heifers, too. Movable shades can work well in pasture situations.

NDSU Agriculture Communication