Wetting Pens to Control Heat Stress
The picture on the cover of Feed*Lot Magazine (March/April 2002) showed a feedlot that was spraying the pens with water to control dust. This technique will also help the heat load on a pen of cattle. This is very important during a time of heat stress.

Summer Competition for Water Space
Aggressive animals may keep some animals away from the water tanks or troughs during very hot weather. The ability of cattle to control heat stress will depend on the amount of water available. We have seen some feeders add supplemental tanks during very hot weather to give cattle extra space.

Feedlot water tanks come in all sizes and shapes. One of the needs is large valves that let adequate water enter the tank. This is very important for low pressure systems. Some tanks are designed for two water levels, one for summer and one for winter. This will help when using a constant flow system during the winter.

Water Temperature
Cool water is preferred, but the amount of water available is much more important. Water stored above ground will warm up to the temperature of the air around the tank. Water from wells or underground storage will be cooler than water stored above ground.

Watering Space and Location of the Water Trough
The critical issue for heat stressed animals is the amount of space available, and not usually the location of the water tanks. A 7 or 8 foot trough that will hold 40 to 50 gallons is often used for a 150 head pen. Longer tanks up to 10 to 12 feet in length that will hold up to 100 gallons are available for big pens. We suggest using longer troughs because many times the head per pen is increased to more head than originally planned. Skimping on water space is a dangerous tactic.

Practically all areas of cattle feeding have a time when there is hot weather with heat stress on the cattle.

For hot climate areas we suggest you place the tank in the middle of the pen. We have noted some feedlots have the water troughs in the feed bunk line, so the trough can be inspected and managed.

Controlling Feed Particles in the Water Trough
Cattle will eat and then head for a drink of water. To help control feed particle in the water tanks or troughs, we suggest placing the water tank or trough at least 30 feet from the feed bunk. If the trough or tank is close to the feedbunk more feed from the last meal is deposited in the water tank. Troughs are easier to clean than tanks.

Clean Water
Manure in a water tank is bad news. One of the daily jobs for feed lot employees is to inspect the water tanks. Regular cleaning of tanks is a must. Many feedlots have a loyal and dedicated person or persons that are assigned this important task. One feedyard comes to mind where all employees share this important task.

Water Storage Management
Water storage tanks may be needed if wells cannot keep up with the volume needed for the livestock. In addition, during a power outage a reserve of water in storage is ideal. Many feedlots have emergency generators, so additional storage is not needed if the wells can keep up.

Emergency Monitoring of Water Supply and Outages
Emergency monitoring of a limit of water supply or electrical outages should be considered. This can be as simple as a light on the wells if they are not working, or as sophisticated as remote communications to a twenty four hour managed location.

Tactics for New Cattle
We have seen some feedyards offer hay to the cattle before they are turned into pens where water is available. This is an interesting tactic. The idea is to get a few bites of feed in the animals before they drink and fill the rumen with fluid and limit the space for feed. Yet, for long hauled cattle in the heat of the summer, one may need to offer water promptly after unloading.

For new cattle extra water tanks in the pen are needed when the weather is hot and muggy.

Tactics for Cattle from Fescue Pastures
Cattle from endophyte infected pastures have constricted blood vessels. The cattle in hot weather will congregate around the water tanks. They will even put their feet in the tanks to try to get some cooling. Plenty of space for drinking is needed. In some cases a tactic is to let the tanks run over to provide a wet area for the cattle to cool their feet.

A better tactic is to create a shallow area of water in the pen as this would prevent the cattle from congregating around the water tank. Individual attention of critical stress animals is needed including wetting the cattle down.

Salt Content of Rations
Excessive salt will stimulate water intake. I have heard this argued both ways to help heat stress by insuring extra water intake. Caution: if feedyards force feed salt through the supplements, then it is critical to have plenty of water volume and watering space.

Comments or questions regarding this or any article by Dr. Sprague can be sent to 625 Grandview, Newton, KS, 67114. (c)