[Image: cattle]Safe supplies of water are absolutely essential for livestock. If livestock do not drink an adequate amount of safe water every day, intake of feed (roughages and concentrates) will be reduced, production will be lowered and the livestock producer will experience an economic loss.
Water constitutes 60 to 70 percent of the body of livestock. Consumption of water is more important than the consumption of food nutrients, the amount depending upon the weather and the character of food consumed. Animals should be given all the water they can drink. Stress may occur in an animal deprived of the chance to drink sufficient water, and actual dehydration may result.
For example, dry cows require about 8 to 10 gallons of water daily. With cows in their last 3 months of pregnancy, daily consumption may rise to 15 gallons. Those in milk need about five times as much water as the volume of milk produced, and calves require much more water after weaning than before. Ignoring this fact may result in a growth check in calves from which they may never fully recover.
Livestock may have health problems as a result of substandard quality water. Poor acceptance and lower intake, as well as drinking mineral or organic contaminants, may be the causes of poor performance and nonspecific disease conditions, although no major livestock health problems associated with water quality have been reported.
Decisions need to be made in evaluating the quality of water for livestock including: whether or not performance of livestock will be affected; if water could serve as a carrier to spread disease; or if the acceptability or safety of animal products for human consumption will be affected.
Several elements found in water seldom offer problems to livestock because they do not occur at high levels in soluble form or because they are toxic only in excessive concentrations. Examples of these are iron, copper, cobalt, zinc, iodide and manganese. These elements do not seem to accumulate in meat or milk to the extent that they would cause a problem.
The most common water-quality problems affecting livestock production are:
· High concentration of minerals (excess salinity)
· High nitrogen content (nitrates, nitrites)
· Bacterial contamination
· Heavy growths of blue-green algae
· Accidental spills of petroleum, pesticides and fertilizers
Livestock tolerance towards minerals in water depends on many things – kind of animal, diet, age, season, climate, kind of salts in the water, and physiological condition of the animal. Palatability (taste) may cause poor acceptance and lower intake if water is inferior. Livestock restricted to waters with high salt content may suffer physiological upset or death.