Heat stress is coming, and it’s going to cost you

The USDA reported heat stress alone cost the beef industry over 75 million dollars in the last decade. This amount is probably short if you start thinking of all the things heat stress affects.

Heidi Doering-Resch

Director of Beef Technical Services / Form-A-Feed

Email Heidi Doering-Resch

Not only do we know feedlot performance is reduced, but we have sick cattle, deads, lost intake, spoiled feeds and recuperation time to pencil in. Add to this the safety of your feedlot staff, and you have money being invested in every avenue of the yard during this time.

If you are prepared for the heat ahead of time, you will be set up to better deal with cattle under stress as well as having safety precautions in place for your staff.

Below are a few ways you can be proactive this year:

First and foremost, be prepared. Sign up for heat stress apps, alerts and notifications to help set your operation up to deal with a heat event. I encourage you to post a temperature-humidity index chart in your feedlot office and use it to help prep your feedlot crew for dealing with the varying degrees of heat events (Figure 1).
Provide more water space per head. A minimum of 2-plus linear inches per head space is recommended during summer months, and make sure water is clean and accessible.
Utilize feed-grade products proven to help mitigate heat stress. Many products fail to provide research proving they reduce internal temperatures or help mitigate energy loss due to reduced dry matter intake. Find the products that prove this and utilize them.
Provide shade or shelter. This helps drop the “feels like” temperature anywhere from 25 to 50ºF. Shade also helps animals reduce their internal temperature by 1 to 3ºF, depending on external and ground temperature.
Provide mound sprinklers. Do not mist cattle; the hide on the animal must get wet to cool the animal, assuming there is a 5-mph wind. In most cases, wetting the surface of the pen will do a better job at reducing pen surface temperature and work co-efficiently with a sprinkler to cool cattle.
Increase pen space per head. Social dynamics are important to understanding how animals will react during heat stress. Remember, sick cattle will be the ones pushed out from shade, so pay close attention to those animals prior to and during heat stress.
Provide adequate fans in barns to help move air off the backs of animals and facilitate cooling. Pack and slat barns help alleviate high ground surface temperatures, but you must still have air movement to cool livestock. Setting up fans will help improve body cooling as well as air quality in the pen.
Keep packs clean and air fresh by cleaning perimeters. When bedding, do so early in the day so cattle are not moved during peak heat.
Keep feed in bunks fresh. Feed should be cool to the touch even during hot days. Feed refusals and moldy feed in the bunk will not entice cattle to consume feed once they have decided to come back to the bunk. Understanding your bunk calls and keeping fresh feed in front of them will help digestion during a time when the rumen is functioning at less-than-ideal efficiency. Remember, moldy feeds reduce fiber digestion and increase instances of having a more acidotic rumen environment.
Do not knock down more fermented feed than what will be used that day. Keep molds and yeast levels to a minimum, which will also help mitigate feeding hot feeds. Molds and yeast wreak havoc on the rumen when things are already operating less efficiently. Allowing feed to heat prior to feeding will only add to this challenged rumen as well as lead to an increase in feed refusals.
Remove feed refusals from the bunk and deliver fresh feed. If cattle reduce dry matter intake further than you anticipated, be sure to remove the refusals so palatability and intakes are not compromised.
Feed early in the morning, with the majority of feed being delivered once ambient temperatures are starting to come down (i.e., 30 to 70). Ideally, 30 percent in the morning and 70 percent at night.
Control weed growth around bunks and parameters. By doing so you’ll reduce flies, rodents and other pests that make animals move, thus producing extra heat from movement during stress.
Do not process cattle during hot days. Research has indicated vaccinations are less effective if animals’ internal temperatures are elevated. Additionally, new implant technologies are available to reduce the amount of times through the chute. Consider use of these technologies if you know your cattle will be going through the chute for re-implant during periods of high heat and humidity.

Being aware of these key management tips will help better prepare your cattle, your staff and your pocketbook during the summer heat stretch ahead. Be proactive and have your emergency plans in place. Heat stress is nothing to be taken lightly and can take a negative toll on both livestock and humans alike.