Winters with above normal snowfall are beneficial to improve water quality in pasture dugouts. With a large spring runoff, dugouts can over fill, allowing for some of the water from last year to be “flushed” out. If the water from last summer had high amounts of total dissolved solids or mineral content; the flush will reduce the concentrations.
In 2017, a grazing reserve in north-west Saskatchewan experienced cattle losses which was directly traced back to water quality. There was very little runoff that spring and the summer was very hot. This increased the amount of water the cows consumed daily. Evaporative losses were high which resulted in the minerals in the dugout water to become more concentrated. Water test results indicated high levels of minerals, including sulfur. It was determined that the cows died from polio, which is caused by high levels of sulfur in the diet (including water). Approximately 200 head died within 7 days of being turned out into this paddock.
Low quality water can reduce animal performance. High levels of total dissolved solids reduce the amount of water animals consume. If they do not drink adequate amounts of water, forage consumption decreases. This reduces milk production and growth rates of calves or backgrounding animals.
Dugouts that are fenced off and the cattle drink from a tank, or nose pump results in higher animal performance. Work done in Lethbridge by Dr. Walter Wilms (1990) reported an improved weight gain of 15.8 lb. (7.2 kg) for lactating cows and an additional 22 lb. (10 kg) for calves at side over a 30 day trial. Steers on pasture had an additional 44 lb. weight gain in 71 days. The differences in weight gains would not be noticeable to the eye and usually are considered to be “just the year” and accepted.
In some areas of Alberta, well water and dugouts can have high levels of sodium present. Sodium makes up 39% the weight of salt. If sodium levels are above 300 ppm or mg/l, the amount of free choice salt or mineral containing salt consumed will be reduced. This negatively impacts growth and health of the animals.
For more information about water testing and water quality on pasture, Barry can be reached at 403-741-6032.