Heat stress not only affects the productive ability of your cattle but also their ability to conceive and sustain a pregnancy. It is important to understand the effect heat stress can have on reproduction and how you can help minimize the effect.

When cows are heat stressed, they eat less, produce less milk, have reduced immune function and higher SCC, and show reduced fertility. A spike in lameness often follows the hot season.

To minimize heat stress, there are three key things farmers can do to help cows on pasture stay healthy, productive, and comfortable during hot spells.

Effective ventilation management reduces the impacts of heat stress on milk production.

Combating heat stress in the herd requires an action plan to prevent heat stress and address heat stress-related issues.

Farmers enrolled in DHI receive several reports regarding herd performance. The Herd Summary Report (HSR) encompasses three main sections: Milk Production, Reproduction & Genetics, and Inventory. The milk production section has eight blocks—the focus related to heat stress will be on Blocks D, F, and G. The Reproduction & Genetics section has five blocks—the focus for heat stress will be on Block L.

Diving into a dairy’s herd management software can help a producer quantify where the losses are occurring and, with some easy calculations, determine the profitability of investing in cow cooling measures.

Below is a visual representation of what to enter in the report screen to generate charts similar to what is shown in the companion factsheet: “Using Bovisync Reports to Assess Potential Impact of Heat Stress on a Dairy”. Milk Production Butterfat Percent Reproduction Milk Quality Clinical Mastitis and Transition Cow Health

In this fact sheet you will see examples of the resulting data you can use to unlock the power of your herd’s Bovisync records.

Working on dairy farms during hot weather presents unique challenges. Heat exposure kills more people annually than floods, tornadoes, lightning, and hurricanes combined.