After last year’s drought conditions across several regions in the U.S. many producers may want to check their water quality before turning out their livestock.
“Runoff from snowmelt and spring rains may not be enough to replenish depleted ponds and dugouts, and water quality in ponds and dugouts still may be compromised by concentrated levels of salts, minerals, and bacteria,” warns Miranda Meehan, North Dakota State University Extension livestock environmental stewardship specialist.
Michelle Mostrom, a toxicologist in NDSU’s Veterinary Diagnostic Laboratory, recommends producers test their livestock’s water sources for total dissolved solids (TDS), sulfates, and nitrates. TDS measure salts. These levels should be less than 5,000 parts per million (ppm) for most classes of grazing livestock. Elevated levels of TDS may be harmful to livestock health.
Sulfate levels should be less than 500 ppm for calves and less than 1,000 ppm for adult cattle. High levels of sulfate can reduce copper availability in the diet. Elevated levels of sulfates may cause loose stool, whereas very high levels of sulfate can induce central nervous system problems and polioencephelomalacia, a brain disorder in cattle.
Nitrate in itself is not toxic to animals, but at elevated levels, it causes nitrate poisoning. Water sources that receive runoff from fields and confined feeding locations that contain elevated levels of nitrogen are at risk of contamination.
During the 2017 drought, NDSU Extension helped producers collect 94 water samples for laboratory testing; 82 of these samples contained potentially toxic levels of TDS.
“We recommend that livestock producers test water quality prior to livestock turnout, especially if their water sources had elevated TDS last year,” says Janna Kincheloe, Extension livestock systems specialist at NDSU’s Hettinger Research Extension Center.
“Monitoring water quality throughout the grazing season is important because the quality changes in response to climate and environmental conditions,” Kincheloe adds. “The importance will be magnified if the drought continues into the growing season, especially when using a shallow water source and sources with a history of water quality issues.”