Water is an essential fluid for all animals. It is a key component in cells, and comprises between 40 to 80 percent of the body weight of livestock, depending on species and age of the animal. It is the main way nutrients move through and are excreted by the animal. Water helps control temperature, cushion joints, support fetuses and has many other crucial functions. An animal can live without food much longer than it can live without water. When water is lacking, productivity becomes greatly diminished. Weight gain slows, animals become sluggish and seek shade, blood thickens, toxins accumulate and, ultimately, if deprived of water long enough, animals will die. Sources of Water Animals get most of their fluids from drinking water. Many factors influence how much they need, including species, size, age, body weight, weather, and water quality. Table 1 shows the maximum amounts of water needed by different animals.