The heat and humidity of summer are arriving in many parts of Nebraska, as well as the rest of the country. Today I will share with you some of things beef farmers and ranchers do to help make their cattle as comfortable as possible during these weather events.
Heat stress is hard on cattle and other livestock (and people!), especially when combined with high humidity and low wind speeds. Heat stress can reduce an animal’s feed intake, weight gain, reproductive efficiency, and milk production, while increasing their susceptibility to diseases (due to increased stress on their overall body system).
Signs of heat stress can include animals bunching, seeking shade, panting, slobbering or excessive salivation, foaming around the mouth, open mouth breathing, and/or lack of coordination and trembling.
If beef farmers and ranchers see such symptoms they will assume the animal is suffering from too much heat and immediately try to minimize the stress to the animal, especially by reducing handling or movement of the animal. Additionally, the previous health of individual animals is an important risk factor, as animals with past health problems will be more affected by heat stress than animals with no prior health problems. These animals will generally be the first to exhibit signs of heat stress and be the most severely affected.
The heat index commonly reported by media outlets is a good place to start in understanding animal heat stress.
If the heat index is above 100 degrees, animals can tolerate it if shade is available and/or wind speed is at least 10 miles per hour. Shade can be provided by trees, buildings or other sunshades. If providing shade is not an option, you may see beef farmers or ranchers move cattle to outside or parameter pens where the airflow is the greatest or to a higher spot where there may be more airflow. If animals are inside a building that is not climate controlled, it is important that airflow through the building is created (opening windows, having fans, open sides,etc). In addition, the temperature can be lowered by spraying cool water on the roof and walls of buildings where the animals are being housed.
If the index gets above 110 degrees, animals will be stressed regardless of wind speed. If possible, market ready animals should have access to shade and airflow. ALL animals should have plenty of access to cool, clean water. Sometimes you may see beef animals standing in water in an attempt to cool down. This can help them stay comfortable, but it can also be risky if they get down in the water and cannot get up. If a heat index above 110 is predicted, livestock that need to be moved or transported should be out of the facilities by early morning but certainly by noon, if possible.
If the heat index is above 115 degrees, market ready animals should not be moved or handled at all!
If the heat index is above 120 degrees, no activity should occur for animals or humans!
During the heat of summer, beef farmers and ranchers may provide: shade (not always an option), ventilation and air flow, plenty of clean and cool water, skin wetting (if possible) with sprinklers and hoses, and cool water drench (if the animal becomes very distressed – a veterinarian may have to assist with this procedure). If used, sunshades would be high enough off the ground (10 feet or more) to allow for adequate air movement.
If animals are wetted down, the droplet size needs to be large enough to wet their skin, not just the hair. A small droplet size will usually just wet the hair creating more humidity for the animal, thus not helping at all.
During these high heat, high humidity events the best time of day to work beef animals is in the very early morning hours when it is still relatively cool. Beef animals will be hot during the day, and will need several hours in the cooler evening temperatures to get their body temperature to a level that is not distressful.
Beef farmers and ranchers do their best to make sure their animals are as comfortable as possible during these high heat, high humidity weather conditions. The best scenario is a nice breeze and cool evenings!
For more information on heat stress check out Feedlot Heat Stress Information and Management Guide, Heat Stress – What You Should Know to Make Livestock Shows a Success, or How to Reduce Heat Stress in Dairy Cattle.
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Agricultural with Dr. Lindsay 
Reblogged this on Agricultural with Dr Lindsay and commented:
In Eastern Nebraska, our temperatures have jumped the last few days, the nights aren’t cooling down, there is high humidity, and no wind. Unfortunately, this combination can be dangerous for livestock. At UNL, our beef team has been trying to push out resources and information to beef farmers and ranchers to help them prepare for these high heat events.
Last year I did a blog post on heat stress. At the bottom of the post are more resources on how to help dairy animals, feedlot animals, and youth exhibiting at livestock shows. These high heat events are dangerous for both humans and animals.