The Importance of Water to Cattle

Water is the most important nutrient. An adequate supply of clean, fresh water is a critical component of maintaining healthy, productive cattle. At this time of year, managing your cattle’s water supply is more important than ever. Water accounts for at least 50 percent of your cattle’s live weight. Water is required to transport nutrients through the blood, maintain cellular structure, regulate temperature, and much more. In order for livestock to maximize feed intake and production, they need daily access to palatable water of acceptable quality and quantity. Water is also critical for cattle dealing with stress. Insufficient water intake lowers cattle performance more dangerously than any other nutrient deficiency. Dehydration in cattle severely weakens the ability of the respiratory organs to resist and expel disease-causing organisms. In addition, hearing and sight of cattle can be adversely affected by dehydration.

Water requirements can be met, to some extent, by the moisture content of feeds consumed. For example, cattle grazing young vegetative forage at 20 – 35% dry matter will have a higher proportion of water needs than cattle grazing seeded or mature forage which is 75 – 90% dry matter. Water intake is highly related to rumen volume and feed dry matter intake. Higher daily feed consumption is associated with greater rumen volume. Accordingly, greater mature weight is associated with higher rumen volume and dry

matter feed intake. Therefore, for the purpose of the following water requirement estimates, the influence of cow size and rumen volume on water intake is addressed through the influence of feed dry matter intake. The estimates below assume that dry cows consume 2.2% of their body weight and lactating cows consume 2.7% of their body weight in dry matter when consuming an average to moderate quality forage.

At 90 degrees Fahrenheit, a 1100# dry cow will require 13.4 gallons of water per day and an 1100# mother cow will require 17.9 gallons of water per day.

At 90 degrees Fahrenheit, a 1300# dry cow will require 14.3 gallons of water per day and a 1300# mother cow will require 17.4 gallons of water per day. In addition, higher milk producers (30 pounds of milk produced per day) will require 19.7 gallons of water per day.

These estimates are intended to represent total daily water consumption. Free water intake could be lower when cows are consuming feeds of high moisture content.

In conclusion, for each 10 degree increase in temperature above 40 degrees, cattle need about one gallon more water per day. Secondly, for each additional gallon of milk produced, cows will need an additional gallon of water per day. Lastly, The dryer the feed consumed, the more drinking water required.

Information for this article was compiled by Mark Z. Johnson, Oklahoma State University Extension Beef Cattle Breeding Specialist. The referenced fact sheet is located online at OSU Cooperative Extension Fact Sheet ANSI-3299. Estimating Water Requirements for Mature Beef Cows.

Montana State University, U.S. Department of Agriculture and Montana Counties Cooperating. MSU Extension is an equal opportunity/affirmative action provider of educational outreach.