Cattle quench thirst with snow
By HEATHER SMITH THOMAS
Ranchers using fall and winter pastures that are short on stock water, or where water sources freeze in winter can let cows eat snow in regions that get adequate snowfall.
Horses, sheep and wildlife can get by on snow as their only water source, and a few ranchers learned that cattle could manage on snow, but no studies were done on cattle use of snow until the late 1970s. Research studies in Alberta in the 1970s and 1980s, and a study in the late 1980s at the USDA Agricultural Research Service’s Fort Keogh Livestock and Range Research Laboratory at Miles City, Mont., by Don Adams confirmed and documented the feasibility of this use. Adams is now a professor of Animal Science with University of Nebraska-Lincoln. His extensive winter water consumption study fitted each cow with an electronic identification tag.
Key Points
• Cattle don’t need to drink water if they can lick snow.
• Snow consumption is a learned behavior; cattle quickly learn it by watching others.
• Eating snow instead of drinking water has no adverse affect on daily gain of calves.
Measuring water intake
“Cows could access water only in a stall [one at a time] with a small water bowl fitted with an electronic water meter. When a cow entered the stall, her identification, date, time of day and amount of water consumed was recorded,” says Adams.
He found the average water intake per 1,000-pound cow was 4.3 gallons per day and that 2% of the cows drank no water at all during the entire study period (November through February). He concluded they were eating snow and preferred the snow, noting that snow was readily available and did not crust over during the study.
“Only 65% of the cows drank water every day. The others drank every second or third day, eating snow the rest of the time, and some never drank water at all,” says Adams. “Drinking patterns and water consumption did not affect weight and body condition. It was impossible to tell, by looking at the cows, which ones were eating snow.”
A Canadian study, reported in 1990, looked at average daily gain in calves that had snow as their only water source for 112 days. There was no significant difference between groups that had water and those that ate snow, except the “snow” calves ate more slowly, alternating their eating with bouts of snow licking. Total amount of feed intake was the same.
Smith Thomas writes from Salmon, Idaho.
Myths dispelled
Concerns about snow as the only moisture were dispelled by studies in Canada and Miles City, Mont. People thought eating snow during cold weather would require too much energy. “If the animal must produce extra heat to melt and warm snow to body temperature, this would theoretically take 15% to 20% more total energy, and hence more feed.
The cows in the studies, however, had similar intake and weight gains whether using water or snow,” says Don Adams, professor of Animal Science, University of Nebraska-Lincoln.
They did change their eating behavior, eating for a while, licking snow, eating some more, licking snow, etc. Cattle consume small amounts of snow throughout the day, whereas animals using water drink only once or twice a day. Intermittent feed and snow consumption seems to minimize thermal stress, and heat created by digestion of forage is enough to warm the snow to body temperature.
It was also thought that cattle deprived of water would suffer impaction, but impaction is only a problem when cows eat forage with low digestibility and inadequate protein to service rumen microbes. “The deciding factor on whether animals can winter on some ranges is not the water source, but the nutritional content of the feed. Cattle may need a protein supplement to utilize it best,” says Adams.
This article published in the January, 2010 edition of WESTERN FARMER-STOCKMAN.
All rights reserved. Copyright Farm Progress Cos. 2010.