With summer in full swing, high temperatures are here to stay. Increasing temperatures can have a multitude of negative effects on dairy cows, including hoof problems that rear their heads later on.
Ingram brad
Brad Ingram
Midwest Regional Sales Manager / Bovine Hoof Care Expert / Vettec Inc.

It’s critical to avoid heat stress now to get ahead of lameness on the dairy.

Causes and symptoms of heat stress

Cows are at increased risk of heat stress when temperatures exceed 68ºF for extended periods. High humidity and little to no breeze can increase the risk even more. Because summer is also the peak season for flies and pests, cows tend to group together to combat stinging and biting insects. As they gather, heat transfers from one animal to another, and the added body heat of the herd contributes to heat stress as well.

Observe dairy cows frequently for signs of heat stress and take precautions when hot and humid weather is forecasted. Common signs and symptoms of heat stress include:

  • Excess standing: During the hot summer season, a cow’s natural response to heat is to stand. Because a cow generates heat when it lies down in a stall, excessive standing, grouping and huddling of a herd are visible signs of heat stress. As heat stress progresses, cows generally stand three to four hours more per day than usual and refuse to lie down.

  • Increased respiratory rate: Since cows are unable to sweat and alleviate their body heat, labored or open-mouth breathing and panting are the animal’s way of introducing cooler air into its body. If a cow maintains an increased respiratory rate with excessive saliva or drooling, heat stress is likely the cause.

  • Changes in behavior and activity: Similar to a human’s reaction to extreme heat, cows alter their behavior to reduce stress when exposed to extreme temperatures. Like a human, when a cow experiences heat stress, its activity and energy levels decrease. If a cow appears agitated, restless and, in extreme cases, lame, heat stress may be the cause. Other changes in behavior include reduced feed intake and increased water intake.

Heat stress and lameness issues

During extreme temperatures, cows stand to allow more of their surface area to disperse heat into the air. Although cows are tough, their heavy bodies cannot withstand long periods of standing.

Advertisement

The extra pressure from excess standing affects the integrity of the hoof, thus restricting blood flow and oxygen needed to maintain healthy hooves. As a result, cows are more prone to injuries and infectious claw lesions as they put extra pressure on their hooves.

Blocking can help, regardless of the injury or condition, to keep milk production moving. Hoof care professionals place a wood or rubber block on a healthy claw to elevate and restrict the affected claw. This treatment option will elevate the injured claw off the ground, and it will heal faster and alleviate pain.

Different adhesives can be used to adhere blocks on the claws to increase the cow’s comfort level. For best results, only apply the necessary amount of glue to hold the block firmly to the foot. Spreading the adhesive evenly across the block ensures the glue dries smoothly and reduces the chance of sharp edges forming that could perforate the cow’s heel. Blocking helps make the cow more comfortable and, therefore, allows farms to maintain optimal milk production.

Managing heat stress

There are different tips and techniques farmers and hoof care professionals can use to prevent heat stress and lameness. Some examples include:

  • Maintain regular cool-off periods and keep cows inactive until temperatures decline.

  • Alter milking and trimming routines to avoid additional headlock time. Mornings and nights are the best times for herd movements to minimize exposure to peak heat hours.

  • Install sprinklers, misters and barn fans for ventilation and cooling.

  • Create shade in outdoor environments to provide more comfort.

  • Provide readily available water sources within short walking distances.

  • Make sure the herd receives vital nutrients with continued feeding periods to maintain milk production. Discuss any adjustments to feed ratios with a nutritionist.

  • Pay extra attention to calves in the warmer months to keep them happy and healthy.

As summer temperatures increase, so does heat stress and standing time. The results of this are often seen a few months later, as dairy farmers tend to see an uptick of lameness in the fall. Talk to a hoof care professional about the importance of adopting a good hoof care protocol during summer months and the best options for your dairy environment.  end mark

PHOTO: A combination of water and fans helps to cool cows and reduce the negative impacts of heat stress, such as increased standing time. When cows spend more time on their feet, they are likely to display lameness problems a few months down the road. Photo courtesy of Vettec.

Brad Ingram oversees states ranging from Michigan to Montana as well as all Canadian provinces. He travels frequently educating dealers and trimmers at hands-on workshops and represents Vettec at trade show events. Brad began working with the company in 2018.

Brad Ingram

  • Brad Ingram

  • Midwest Regional Sales Manager
  • Bovine Hoof Care Expert
  • Vettec Inc.
  • Email Brad Ingram