Managing Heat Stress this Summer

With the summer months fast approaching, hot and humid weather will soon be upon us. Is your barn or facilities ready for the heat? One of the biggest problems faced by dairy farmers during the summer is heat stress in the herd. In climates where humidity can rise just as fast as the thermometer, heat stress is even more prevalent.

When cows get hot, they sweat to cool off; if its humid, the sweat will not evaporate fast enough and the cows will not cool. they will also pant to cool themselves, but it is fairly ineffective. Once a cow is experiencing heat stress, she will decrease her feed intake, which results in a drop in production. Other drawbacks include reduced reproductive efficiency and decreased feed efficiency.

Here are four easy tips to help combat heat stress in any size herd:

1.Increase Water Access: During periods of heat stress, cows will drink more water of it is available. It is important that the water stays cool and does not become stagnant. If the cows have access to automatic waterers, they should be kept clean to keep water flowing. If cows are pastured during the day, be sure their water source, if it is not a creek or pond, is staying full at all times. A float system on a water tank is a good way to keep the tank full and from getting stagnant.

2.Provide Shade/ Cooling Systems: If cows spend a majority of their time outside, either on pasture or in a dry lot, providing shade will give them a break from the sun and allow them to stay cooler. Trees are a great natural shade source, but if that is not available, structures without walls will provide shade without stopping airflow. These shades should be built near or over where cows will be fed, as it will encourage them to eat.

If cows spend their time inside, cooling systems can be used to increase air movement and allow cows to cool themselves. Stall barns with large tunnel fans can increase air flow by increasing air inlet. Opening extra windows, doors, or opening mow space for air to come in can be beneficial. Free stall set-ups can utilize fans over the stalls to allow cows to be comfortable laying down. Sprinklers can be put over feed bunks and in holding pens to offer additional cooling.

3Reduce Rumen Heat: One of the main reasons cows reduce feed intake is to reduce rumen heating. The fermentation process gives off a lot of heat and can be very uncomfortable for the cow during heat stress. By feeding high quality forages that take less time to ferment and digest, you can keep cows eating more in the heat. Another good way to keep cows eating is to feed energy sources that bypass the rumen, such as molasses or inert fats. These types of feed do not need to be fermented and are absorbed by the small intestine. They are quick sources of energy that are considered “cool” energy sources. When feeding inert fats or molasses, be sure to clean mangers daily and feed small amounts, as they are quick to spoil in hot weather.

There is some additional research into feeding yeast cultures to help reduce rumen heating, however, it is fairly new research. There are scholarly articles available on this topic if you are interested in the research.

4. Work in the Cool of the Day: This is a great tip for both the cows and the employees. Though milking times cannot be changed, feeding cows most of their feed during the morning hours or later at night can increase feed intake and reduce spoilage of the feed. Cows will be more willing to eat when the day is at it’s coolest. Pen moves, reproductive services and other tasks should also be done at the coolest point of the day to reduce stress on the cows and allow for optimum outcomes. 

These four tips can be easily implemented in any facility and there are many low-cost options for cooling systems to fit a budget. there are other ways to reduce heat stress, but these four key points are a great starting point.


Submit A Comment

Leave a Reply