Effects of water temperature on its intake.

Water is the most abundant nutrient in the body and a critical nutrient for all classes of beef cattle. Cattle need access to ­adequate supplies of clean water at all times and should not have to travel long distances for water. Water is required for a wide variety of body functions in cattle. It is needed for body temperature regulation, growth, reproduction, lactation, digestion, nutrient use, mineral balance maintenance, pH buffering of body fluids, waste removal, joint lubrication, nervous system cushioning, hearing, and eyesight.

Not all water must come from drinking. Feeds and forages contain water, and digestion of feeds can produce water in the body, particularly high-energy feedstuffs. Water intake usually refers to free-drinking water plus water from feedstuffs. Pasture forages, green chop, and silage generally contain large amounts of water, while hay and feed grains tend to contain lower amounts of water. Lush forage may be approximately 75 percent water, while forage in the form of hay may be closer to 10 percent water. Water is listed as moisture on a forage or feed analysis report. Subtracting the dry matter percent of a feedstuff from 100 percent yields the moisture percent. High-energy feedstuffs supply more body water during digestion than low-energy feedstuffs.

Water temperature has been identified as affecting animal preference to water. Warm water can reduce intake, and cool water can increase both water and feed intake. Cool water helps cattle maintain a proper body temperature. A recent study found that water intake by cattle increased when water temperatures were below 77°F. This increased water intake is often associated with improved feed intake and cattle weight gains. (There are also production benefits to maintaining cool drinking water supplies for cattle.)  Most groundwater supplies to cattle operations are naturally cool. Ponds generally maintain a constant temperature during the day, but the temperature rises with direct sunlight exposure throughout the day. Deep ponds do not usually warm up to the point they will affect intake. Small water troughs in the summer and shallow sloughs and ponds may be a concern. Trough water heats up by late afternoon but then cools down during the night. Cattle water intake typically peaks in mid-morning hours and also during the hottest period of the day. Cattle tend to graze during early morning hours, then seek water, and finally seek shade or graze less intensively during hot afternoon hours.