(Table of Contents)

Why is water important?

Water is so common we seldom think of it as a nutrient, but it is probably the most essential and the cheapest of all nutrients. Depriving hogs os water reduces feed consumption, limits growth and feed efficiency, and causes lactating sows to produce less milk. Water affects many physiological functions necessary for maximum animal performance. Among these are temperature regulation, transport of nutrients and wastes, metabolic processes, lubrication, and milk production.

How much water do pigs need?

The water requirements of swine are variable and governed by many factors. Water accounts for as much as 80 percent of body weight at birth and declines to approximately 50 percent in a finished market animal. The need for water is increased when a pig has diarrhea. High salt intake, high ambient temperature, fever, and lactation also markedly increase water requirement.

Water requirement has a relationship to feed intake and to body weight. Under normal conditions, swine will consume 2 to 5 quarts of water per pound of dry feed or 7 to 20 quarts of water per 100 pounds of body weight daily. A rule of thumb is that self-fed hogs will consume 1.5 to 2 times as much water as feed.

Temperature will affect water intake. Additional energy is required to warm liquids consumed at temperatures below that of the body. Lactating sows must have unlimited access to water ( about 5 gallons a day) if they are to milk adequately, and suckling pigs past 3 weeks of age need water in addition to that in sows' milk for optimum performance. Free access to water located near feeders is desirable.

Will water flow rate affect performance?

Recent research shows that water flow rate has little effect on growing-finishing pig performance. However, pigs will take longer to drink when water flow rate is reduced. Suggested water flow rates based on phases of production are listed:

Required Water Flows

Nursing pigs and hot nursery pigs:
1 cup (250 cc) of water per minute

Pigs from 25 to 50 lb (nursery):
2 cups (500 cc) of water per minute (1 pint)

Pigs from 50 125 lb (grower):
3 cups (750 cc) of water per minute

Finishing hogs, 125 lb to market:
4 cups (1000 cc) of water per minute (1 quart)

Sows and boars:
2 quarts (2,000 cc) of water per minute.

Is wet feeding beneficial to pig performance?

There has been renewed interest in wet feeding, and several "wet" feeders are available. Research with starter pigs indicates that wet feeding results in poorer feed efficiency. However, research with finishing pigs has shown a slight improvement in feed conversion. Probably the biggest concern with wet feeding is the increase potential for spoilage and mold problems from wastage. Therefore, if using wet feeders, feeder management and cleaning will be increased.

Will high levels of minerals in the water source affect performance?

Saline waters are found occasionally throughout the United States and cause concern about their use as drinking water for humans and livestock. Minerals most commonly found in ground and surface waters are sulfates, chlorides, bicarbonates, and nitrates, which form salts with calcium, magnesium, or sodium. The combined concentrations of these minerals are called total dissolved solids. Heavy applications of fertilizers to fields, contamination of runoff water by animal wastes, and severe drought can increase the potential for water quality problems.

Sulfates. Sulfate salts are of special concern because of their laxative effects. Some effects of high levels of sulfates in drinking water for swine are: (1) diarrhea, (2) poor gains and feed efficiency, (3) nervousness, (4) stiffness of joints, (5) increased water consumption, and (6) decreased food intake. Researchers have reported an increase in scouring of growing pigs consuming water containing 3,000 parts per million sulfates, but gain and feed efficiency were not affected. This level of sulfates did not adversely affect reproductive performance of sows.

Nitrates/Nitrites. Nitrites impair the oxygen carrying capacity of the blood by reducing hemoglobin to methemoglobin. The conversion of nitrate to nitrite in water is necessary for toxicity to occur. Research indicates that approximately 100 ppm nitrate nitrogen is generally safe. However, 300 ppm nitrate nitrogen can result in toxicity.

Total Dissolved Solids. It appears that for swine, moderate contamination of water supplies by sulfates or nitrates may be intensified by concentrations of other dissolved minerals. Total dissolved solids (TDS) measures minerals that contribute to the salinity of the water, such as sodium chloride, and calcium and magnesium salts. High TDS may lower the toxicity levels for sulfates and nitrates. Approximately 5,000 parts per million appears to be the maximum safe level of total dissolved solids in drinking water for swine without adverse affect on performance.

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