Cool Cows, Thriving Herds: Support your herd this summer

Matt Dodd, DVM, Ruminant Field Technical Specialist, Diamond V 

When it’s hot outside and you’re sweating profusely, it takes more than water to replenish all the fluids—and what’s contained in the fluids—that you’ve lost. It’s the same for cows in your herd. 

While humans are impacted by heat and humidity, cows have it worse than we do. Humans generally start to feel heat stress when the temperature reaches around 80 degrees Fahrenheit. Cows are impacted much earlier, usually in the upper 60’s. Keep in mind that cows have a big heat generating furnace inside them, the rumen, that impacts their ability to stay comfortable when it’s warm outside.

Impact on reproduction

It doesn’t take much heat and humidity to impact cow performance. Research out of Germany shows that even one hour experiencing a heat index higher than 73 degrees can drop conception rates. Now multiply that potential impact if cows are under stress for eight hours or more at a time during peak heat season.

Additionally, a cow’s body temperature lags behind environmental temperature. While the environmental temperature may peak in late afternoon, a cow’s body temperature continues to rise for several more hours, peaking closer to 9 pm. It’s imperative to keep cooling mechanisms in place even after the sun goes down.

With summer approaching it’s never too early to get prepared to reduce the impact of heat stress on your milking herd. A significant part of that preparation includes providing nutrition tools and resources to help keep your cows hydrated.

Proper hydration is key

Let’s look at hydration at the cellular level. When a cell is hydrated, it can better withstand heat and maintain its structure. When a cell gets dehydrated it loses its ability to maintain temperature control and regular cell function including the breakdown of proteins. To stay hydrated, cows need to drink ample amounts of water.

At some point as the marathon of heat stress continues, water alone isn’t enough. When heat and humidity rise, and cows get hotter and more stressed, drinking water may not provide the relief from heat stress that they need. Even though cows don’t sweat much, they do lose nutrients—especially potassium—through increased respiration. Those lost elements need to be replaced to keep cows performing during hot weather. 

Ice the heat

There are opportunities through nutrition support to help cows navigate heat stress more efficiently and recover quicker once heat stress hits. Diamond V™ Ice Plus offers a synergistic, proprietary blend of ingredients that helps cows better regulate body temperatures during heat stress to help lessen the impact of heat stress on milk production and reproductive health.

While it’s difficult to completely protect cows from the stress of heat and humidity, we continue to learn more about ways to prevent the severity of heat stress. There are basic management factors around feeding management, evaporative cooling and other elements that can mitigate heat on the outside of the cow. Innovative nutrition tools can also affect how cows handle heat stress from the inside, including ingredients that help them stay hydrated and functioning at the cellular level.

Talk with your nutritionist or your Diamond V representative about including Diamond V™ Ice Plus in your ration this summer.