Take These Steps to Avoid Heat Stress in Calves

Posted on November 2, 2012 in Starting Strong - Calf Care
From Steve Hayes, DAY 1 Technology

We may enjoy the warm summer months, but we can’t necessarily say the same for our calves. As temperatures rise, heat stress becomes an increasing concern for these young animals.

Steve Hayes with DAY 1 Technology said heat stress can have several effects on calf health, including:

  • Rapid dehydration
  • Lowered feed intakes
  • Reduced growth rates
  • Reduced function of the immune system
  • Reduced circulating immunoglobulin concentrations
  • Increased stress hormone concentrations

Several signs may point to heat stress in your calves. Decreased appetite, higher respiratory rates, open-mouthed breathing and “sluggish” behavior may all be indications that your calves are suffering from heat stress.

According to Hayes, four factors can affect the heat load placed on a calf:  ambient temperature, relative humidity, air movement and solar radiation. Managing these factors through the following activities can help to limit heat stress while maintaining calf health and performance.

Limit sun exposure
It’s best to keep calves in the shade. If you use greenhouse barns or translucent hutches, make sure the animals have at least 80 percent shade. Remember that black calves will absorb more sunlight than white calves, making them more susceptible to sun exposure and heat stress.

Increase air flow
If your barn is naturally ventilated, make sure you have all vents completely open on hot days. Also be sure to pull up sidewall curtains. Don’t pack hutches too closely together; be sure to maintain adequate space between hutches to allow for good air flow. You may also consider raising hutches with blocks to increase air flow under the hutch.

Rethink bedding
Straw bedding is great for reducing respiratory problems and keeping calves warm in the winter time, but this insulator often isn’t the best choice for bedding in the summer months. Consider sand bedding to lower the temperature around the calf.

Provide plenty of water
According to Milk Products, LLC, “calves exposed to heat stress can consume 3 to 6 gallons of water per day.”  If you see your calves are running low on water, you may need to add a third feeding to prevent dehydration.

Manage stressful activities
The best time to perform stressful activities (moving, vaccinating, dehorning, etc.) is in the morning. Although evening temperatures are cooler, calves’ body temperatures are still elevated at this time. Wait until morning when calves have had time to cool off.

Category: Animal health
Heat stress
Starting Strong - Calf Care