As an essential nutrient in pig production, fresh, high-quality drinking water tends to be taken for granted. Water is too often overlooked as a potential source of a problem, even if performance issues arise within a herd.

Yet, water quality relates to pig health, nutrition, animal management and profitability. However, chemical or microbiological issues can degrade water quality and end up hurting animal performance. Actually, sudden changes in animal performance can be a signal that you may want to consider water quality testing within your operation.

“If your operation is served by organized rural water systems, they are regulated like public water supplies, which would already be doing periodic testing,” says Allan Stokes, National Pork Board’s director of environmental programs. “However, if there were a leak in the feed line running to a specific building, there may be localized water contamination at the location that would not be reflected in the rural system’s tests.”

Of course, ideal water quality is not always possible to maintain. For example, water from ponds or other surface sources may have elevated bacterial levels. USDA provides a useful information center containing discussions on many water quality aspects.

If water ever appears cloudy, dirty or frothy, or has an objectionable smell or taste, there may be a quality problem and it should be tested for contaminants.

Bacteria may be one of those contaminants. When we look at bacterial contamination
of water, it should be viewed as a serious problem in pork production,” says Tom Guthrie, agricultural educator, Michigan State University. “The most common pathogenic bacterial contaminants of water are Salmonella, Leptospira and E. coli.”

As a guide, your water should have fewer than 100 total bacteria per milliliter (or cubic centimeter) and fewer than 50 coliforms per milliliter of water. “Chlorination can help destroy disease-causing organisms,” Guthrie says. “However, if organic matter is present in the water, the disinfection properties of chlorination can be substantially reduced.”

Nitrates in the water may be the source of another water quality problem. Runoff from
farmland which received nitrogen fertilizer or manure may increase nitrate concentrations in the water supply.

“Nitrates in the water often indicate bacterial contamination,” Guthrie says. “When nitrates are converted to nitrites they can interfere with the blood’s oxygen-carrying capability and cause bigger problems.”

The maximum tolerable amount of nitrates plus nitrites is 100 parts per million, with a maximum of 10 ppm for nitrites, according to Gary Cromwell, swine nutritionist at the University of Kentucky.

If high amounts of nitrates or minerals are present, you can use an ion-exchange device that replaces the calcium and/or magnesium with sodium. A reverse-osmosis device can be used that essentially moves water through a membrane which blocks the passage of contaminating compounds.

Excess minerals found in water can further reduce quality. The total inorganic matter dissolved in water is measured as Total Dissolved Solids. Water with a high TDS might contain excess levels of calcium, magnesium or sodium. Generally, water with less than 1,000 ppm TDS does not cause problems in pigs. With TDS levels over 1,000 ppm, diarrhea or reduced water consumption may result.

As for water alkalinity, a pH between 7 and 8 is considered mildly alkaline, and a pH of 10 is highly alkaline. Excessive alkalinity can cause digestive upsets in livestock. The acceptable range for pH is 6.5 to 8.5, Guthrie says.

Hard water is a fact of life in some rural areas and is usually caused by high levels of calcium and magnesium. Hard water does not usually cause swine performance issues, but it can lead to scale build-up in water pipes and other equipment and it reduces flow rate to waterers. Installing a water softener may be a wise investment if water hardness is a factor in your operation. It also will improve power-washing and overall cleaning effectiveness.

Any water issue that reduces your igs’ water intake will eventually impact eed intake and performance. Maintaining dequate water intake is critical in any roduction phase but especially for lactating ows and iglets from birth through the eaning nursery stage.

Water-use recording devices can alert ou to possible problems — whether that
is excessive or inadequate water use. For example, if water consumption declines for three days in a row, you need to evaluate pigs closely for illness and check the water supply for quality or flow rate changes that may have occurred.

Chloride at 250 to 500 ppm causes brackish taste which can cause hogs to back away from the waterer. Iron levels at 2 to 3 ppm can cause blockage to develop in nipple waterers.

Sulfates may cause a putrid odor in water and discourage water consumption, particularly in young pigs. “Sulfates also can act as a laxative and may lead to diarrhea,” Guthrie adds.

Water is an essential nutrient for pigs of all ages. It affects vital physiological functions required to maximize animal performance. Keeping a close eye on water quality can help prevent contaminants from tapping into your bottom line.

Douse Water Problems

The federal Safe Drinking Water Act requires periodic testing and laboratory analysis of public drinking water supplies by certified laboratories. However, if your operation draws water from a private source, consider annual water tests. That’s especially true for shallow wells and whenever you suspect a problem.

To find a certified laboratory, check with state authorities, as they maintain a listing. You also can find information at Other testing options would include your county health department, a commercial laboratory or your local Extension service. Look online or in your local yellow pages under “Laboratory-Testing.” Be sure to verify that the laboratory is certified by your state to conduct drinking water testing.

Several chemical tests are routinely done to determine water quality. “Of these, Total Dissolved Solids, pH, iron, hardness and nitrates/nitrites are a good initial screening,” says Eric van Heugten, Extension swine specialist, North Carolina State University.

If you suspect a problem, check first with the laboratory, as specially prepared containers may be required to collect and submit a sample. “The water outlet should be cleaned and sterilized prior to taking the water sample, especially if determining bacterial counts,” van Heugten says. To obtain a representative sample, he recommends letting the water run for a couple minutes prior to collecting the sample.

If tests show unsatisfactory results, additional analysis may be needed to determine the exact source and issue of contamination.