Water Requirements for Livestock PDF

 Water Important for Livestock Water is important for all organisms. Water makes up one-half to two-thirds of the body mass of adult animals and more than 90% of the body mass of newborn animals. Water is an essential constituent of almost all secretions of the body. Within the body,...

 Water Important for Livestock Water is important for all organisms. Water makes up one-half to two-thirds of the body mass of adult animals and more than 90% of the body mass of newborn animals. Water is an essential constituent of almost all secretions of the body. Within the body, water is a universal solvent that facilitates cellular biochemical reactions involving digestion, absorption, and transportation of nutrients. The aqueous medium of water helps different digestives juices and food components interact, enhancing digestion, and helps in the excretion of waste products in the form of urine,  Because of the high specific heat of water, it helps in regulating body temperature, by absorbing the heat generated through different metabolic reactions. Water also regulates body temperature through evaporation as sweat or transports heat away from organs through blood. Water provides shape to body cells. Water helps in maintaining the acid-base balance of the body. Water acts as a cushion for tissue cells and the nervous system and protects the various vital organs against shocks and  Sources of water: Most of the water which is utilized by the animal body is ingested, either as such (drinking water) or as a component of the food. There is a further available source which is provided by metabolic process and which is thus called metabolic or oxidative water. When the carbohydrate glucose is oxidized to furnish energy for body processes, carbon dioxide and water result: C H O + 6O ‑‑‑‑‑ 6CO + 6H O 6 12 6 2 2 2  By calculations from this equation, it can be shown that the metabolism of glucose yields 60 percent of its weight as water and protein produces approximately 40 percent of its weight as water, while in the case of fat the figure is over 100 percent. For example, cellular oxidation of 100 g of protein, carbohydrate or fat yield 40 g, 60 g or 109 g of metabolic water, respectively.  Water-holding capacity:
The ability to absorb and maintain free water. The water- holding capacity of a feedstuff is primarily governed by the types of non-starch carbohydrate (fibre) in the feedstuff. Feedstuffs with high water-holding capacities are sugarbeet pulp, linseed meal, lupin seeds and a certain varieties of barley, wheat and other cereals. Increased intake of non-starch polysaccharides (with a consequent increase in water-holding capacity) often decrease the transit time of feed in the gastrointestinal tract.  In poultry, feed stuffs with high water-holding capacity tend to increase endogenous losses of nutrients from the gut. Nutrient availability in poultry is negatively correlated with the water-holding capacity of the feed. Increased water intake and digesta viscosity lead to wet and sticky faeces, increasing the risk of health problems and encouraging the colonization of the gastrointestinal tract by pathogens. Finally, the gastrointestinal tract of animals is larger (and proportionately heavier) when they are fed diets with a high water-holding capacity. Water excretion: Water losses from the body are through urine, feces, sweat, lungs and production of milk and eggs. Animals have a limited capacity to reduce the amount of water excreted through the urine when suffering from water deprivation. Loss of water through the feces varies with species, with cattle feces having higher moisture content than sheep feces. Urinary water loss depends on weather and on the type of food consumed. Animals that consume high-fibrous diets excrete more water in their feces , Fecal water excretion is higher in cows (30%–32%) compared to sheep (13%–24%) that void pellet-type dry feces to minimize water loss.  Water deprivation: Water deprivation When the intake of water, either as liquid or as part of the food before or after metabolism, is insufficient to maintain the insensible losses of water through the skin, lungs and obligatory urine production by the kidneys there is a decrease in circulatory volume which in turn leads to a fall in blood pressure, a rise in heart rate, circulatory collapse, renal failure and death.  Animals tend to become highly irritable and bad tempered. and death will flow if severe water deprivation continues long enough. Some desert animals such as the camels can tolerate more severe water dehydration than man or the dog without suffering an explosive heat rise. Animals deprived of water refuse to conserve food in early stages of dehydration and will not eat dry feed until after they have had a drink of water.  Water requirements: 1. Environment: Increased environmental temperature and humidity enhanced the water requirement in comparison to cold environment because of increased evaporative losses in hot and humid environment. Young animals have higher water needs per unit of body size as compare to large animals. 2. Dietary factor: High fibrous diet like dry roughages increases water requirement than less fibrous diet. Salt and uric acid excretion requires more water. So intake of salt and protein whose end product is uric acid increases the water requirement. If succulent feed is given to animals than dietary water requirement is reduced. Water consumption, when expressed by unit of body weight for non-heat-stressed, nonlactating cattle, is around 5% to 6% of the body weight per day (or 2–5 kg of water for every kg of dry feed consumed) and can go up to 12% or more under heat stress.  3. Animal factor: Age, stage of growth, level of production, activity, health condition and pregnancy has a direct effect on water requirement. Other factors are salinity and sulfate content of water, temperature of water, frequency and periodicity of watering, social or behavioral interactions of animals with environment, and other quality factors such as pH and toxic substances affect water requirement and intake. Birds require l ess water as co mpar ed to mammal s because uric acid is the end product of protein metabolism in birds as urea in mammals. 1- Animals that are gaining weight require more water than those that are losing weight. 2- Animals with diarrhea or fever will have a higher water intake as will those with a high salt or protein intake. 3- Pregnant and lactating animals require more water than those not pregnant or milking 4- Increased activity increases the water intake of animals. 5- Animals consuming high levels of dry matter will drink more water than those consuming feeds high in water intake. Average water requirement of farm animals. Animal L/day Beef cattle 25-65 Dairy cattle 40-120 Horses 30-45 Sheep and goats 3-15