Since it’s time to cool cows again, it’s time to tune up your cow cooling systems. The first thing is to clean your fans; dirty fans reduce air speed by 50 percent. With the price of energy these days, it is important to keep the fans clean. It is not against the law to clean fans twice a year, especially if you have dusty roads near the barns. The faster the air movement around the cow, the faster the sprinkler water will evaporate from the cow’s skin and the cooler they will be. The cooler the cow is, the more food she will eat and the more milk she will produce. Fans will use the same amount of electricity if they are dirty or clean, so keep fans clean. The second part of the cow cooling process is the use of water to be evaporated off the cow body to take the heat with it and cool the cow. This means that you only need enough water to get the cow wet to the skin, then turn the water off and the fans will evaporate the water from the cow. Adding too much water reduces the efficiency of this process. The excess water runs off the cow, to the floor and then to the lagoon. To conserve water, you should adjust your sprinklers to just add enough water to soak the cow’s skin and start to run off the cow. The length of the off cycle should be long enough to let the fans evaporate the water off the cow and then start again. There are some very good sprinkling controls on the market that are easy to adjust and will add more cycles as heat increases. One of the [2006] Dairy Check-Off Projects was to determine the results of turning sprinklers off on one side of a barn at the Dairy Research Unit at midnight and turn them on again (by timer) for one hour after the cows came back from the milking parlor. Our nighttime cycle for this particular barn is one minute of water every ten minutes. This is a very short cycle compared to most dairies. The water savings was 600 gallons of water per cow from the end of May to the first week in October. On a 1000-cow dairy this will be 600,000 gallons of water saved, 1.2 million gallons on a 2,000-cow dairy. Remember that the less water you use, the drier the floors and the lower the humidity in the barn. Sprinklers are stationary, cows are mobile. All it takes is a timer in front of the sprinkler controller to shut off the water when cows are in the parlor, laying down, etc. If you don’t have timers on the sprinklers, you are wasting water, have soggy cows and are filling your lagoon. Less is more. PD —Excerpts from University of Florida Dairy Update, Vol. 7, No. 2 David R. Bray, Dairy Extension, University of Florida