There is an endless amount of variation in the cattle business. Currently, in the United States and Canada, some regions are experiencing severe drought, while other areas are abnormally wet. On top of these environmental variances, there are also vast differences in genetics, the available forage species, management practices and marketing strategies, just to name a few. There are no two operations that run their cattle the same way — but when July rolls around, I think there is one thing that we can all agree on: It’s HOT!

Being able to combat the summer heat with air conditioning has become an amenity that we humans often take for granted. According to the Energy Information Administration, 48% of all energy consumption in American homes is a result of cooling and heating. This is a staggering figure — especially considering that modern air conditioning wasn’t made available to homeowners until 1929. Unfortunately, our cattle don’t have the same luxury of escaping the blistering heat (minus show cattle in coolers, of course). With this in mind, it is important to understand how extreme summer temperatures can negatively impact the performance of our cattle in the form of heat stress and how crucial it is to have a gameplan in place to minimize those negative consequences.

What is heat stress?

The main concern for cattle when dealing with high temperatures — especially when paired with high humidity — is heat stress. Cattle naturally produce energy in the form of heat through a number of different bodily functions. During the winter, the heat cattle produce is used to raise their core body temperature, whereas in the summer, cattle dissipate their produced heat to lower their body temperature. This process is known as thermoregulation. Nutritionist Jill Peine, M.S., authored a great article a few years ago, titled “The dog days of summer: Regulating cattle body temperature during heat (or cold) stress,” that explains the process in detail.

When cattle are not able to dissipate enough heat to regulate their body temperature to around 101 degrees Fahrenheit, they experience heat stress. The Livestock Weather Hazard Guide from the Noble Foundation, included below, illustrates the ambient temperature and relative humidity combinations that produce the greatest likelihood for heat stress in cattle.

How does heat stress impact the performance of cattle?

As we know well by now, the number-one driver of profitability in the cattle business is getting a live calf on the ground. Heat stress can have a number of consequences, but a reduction in reproductive performance is where heat stress has the greatest impact on a producer’s bottom line. For many operations, the summer breeding season plays a major role in determining their financial success for the upcoming year. However, it has been well-documented in a number of both beef and dairy studies that heat stress in the summer months can reduce reproductive performance due to an increased likelihood of early embryonic death as a result of altered hormone production and impaired follicle development, a reduced intensity of estrus, and decreased libido and semen quality in bulls.

Additionally, summer grazing is the most cost-effective way to put pounds on your cattle, whether in the form of body condition or the weaning weights of calves that will be shipped in the fall. Unfortunately, this is another area where performance is left on the table because of heat stress. When cows are spending less time grazing because of the additional heat load, that means there will be less energy available to produce milk for their calf and less available excess energy to put on condition to prepare for the upcoming winter and calving season.

What can be done to mitigate the effects of heat stress?

The most important and practical way to reduce the negative effects of heat stress is to ensure access to cool, clean water and adequate shade cover. Mature cows that are nursing calves can consume upwards of 30 gallons of water per day during the summer — and this doesn’t include the 10 or so gallons per day consumed by the calves themselves. It is also very common to see cattle wading in ponds, streams and other sources of water during the dog days of summer. While doing so will help lower their body temperature, it also lowers the quality and sanitation of the water. If ponds are the only source of drinkable water, producers may be advised to fence off their ponds in such a way that cattle cannot wade into them, thereby ensuring that the water is suitable for drinking. Another cheap form of insurance is to send off pond water samples to test their pH levels and bacterial loads.

Shade is another crucial component of reducing the severity of heat stress. According to the Noble Foundation, shade can reduce radiant heat by up to 40%. Trees provide the most convenient source of shade and also allow for airflow, but if trees aren’t available, portable loafing sheds make for a nice alternative.

After the basics of water and shade are met, there are a few other management practices that can be implemented to help with heat stress:

• Plan all major workings — like pregnancy checks and pasture rotations — to take place as early as possible in the mornings, when temperatures are the coolest.
• Keep a close eye on cattle with a known history of respiratory illnesses. Cattle don’t sweat nearly as much as other species, so most of their heat is dissipated through respiration.
• Provide proper mineral supplementation to assist cattle with shedding their winter hair coat in the spring so they will be “slicked off” come summer.
• Manage the fly population. Cattle with an intense load of flies are regularly seen gathered together, which reduces the air flow per animal unit.
• For producers in fescue country, the severity of the toxicity from endophyte-infected tall fescue increases as the forage matures during the summer, which exaggerates the severity of heat stress. For more information on this topic, nutritionist Sam Strahan, M.S., recently wrote an in-depth article titled, “How can I get my cows out of the shade and grazing fescue pasture?”

How can CRYSTALYX^® Brand Supplements help?

Being proactive is the key to minimizing the severity of heat stress, and CRYSTALYX can be utilized in a number of ways to help animals beat the summer heat. From a nutritional standpoint, products like Blueprint^® 6% Phos with ClariFly^®, IGR Max™ and Mineral-lyx^® with ClariFly^® provide a robust mineral and vitamin program suited to the goals and the budget of your specific operation while also delivering fly control additives. As mentioned above, on top of their known benefits of improving the performance of cattle reproduction, growth and overall herd health, both providing mineral supplementation and controlling the fly population can lower the severity of heat stress.

CRYSTALYX also provides a comprehensive portfolio of low-moisture block supplements that contain the Alltech product FEB-200™, which can drastically reduce the severity of toxicosis from endophyte-infected fescue. Along with the nutritional benefits and feed additives delivered via CRYSTALYX Brand Supplements, they can also be strategically placed in pastures to maximize grazing distribution, along with water consumption.

For more information on how CRYSTALYX can become part of your management strategy for combating heat stress, visit your local CRYSTALYX dealer.