For eons, wild animals in Canada, especially the large herbivores, have relied on snow as their primary water source through the winter. It has been shown that some wild species like reindeer actually prefer snow if given a choice. Can ruminants – especially pregnant beef and bison cows and heifers, do well eating snow?
I have many clients who go to elaborate lengths to make sure their cattle have access to water through the winter. Others use snow and the cattle or bison do very well. Is one as good as the other?
In several studies in Alberta and Montana where cold weather and adequate snowfall were present, all outcomes were very consistent. There was no change in either body fat of the cows and birth weights of the resulting calves. Some studies even followed it further to the subsequent weaning weights of the calves and found them unaffected as well. Fertility and days till rebreeding were also unaffected.
Unless there is inadequate snow or it is extremely crusted from rain, it can be totally acceptable for mature large ruminants (cattle bison and elk). In late pregnancy where fetal fluids increase, and into calving, more water is necessary to produce good quality colostrum and milk. Cattle are generally brought in closer to the yard for calving and access to water is readily available then. For the rest of the time, snow consumption will not have any detrimental effect on your mature cattle.
Fresh snow is very clean and has no fecal contamination, which could promote transmission of internal parasites. You must monitor body condition since lack of water will reduce feed consumption and animals will drop condition rapidly if water or snow is deficient. Gauntness in the flanks is the first telltale sign. Weight loss over the ribs and spine is visible next. Watch the consistency of the manure, as less water causes a dryness and stiffness to the cow patties.
Eating snow is a learned behaviour, so if it’s new to them livestock, may take up to three days to adjust. Keep in mind the requirements for water will drop in the winter as the temperature declines. I use an average rule of 10 per cent body weight or about one gallon per 100 lbs. in summer. It drops to two-thirds or less in the cold winter. Silage feeding also decreases water requirements because of its moisture.
There are many management and cost benefits to eating snow. Stockpiled pastures or remote and protected wintering areas can be utilized. You save electricity costs from heating watering bowls to running pumping systems, not to mention the high initial costs of trenching in lines or purchasing all-weather watering systems. By moving the feeding area the manure is spread out considerably eliminating the need for manure removal. The calving yards can also be kept totally clean until needed.
Safety and environmental benefits
In our area we experienced a drought for a few years so this practice of eating snow took some of the pressure off of farm dugouts or wells which become taxed supplying water year-round. Every year there are one or two wrecks in our area of a producer losing several cattle from falling through the dugout. This almost invariably occurs when producers cut holes in the ice for the cattle to water. Not only do they risk drowning there gets to be a large concentration of manure on the ice, which in spring contaminates the water. I still remember several years ago seeing an aerial photograph of cattle being watered through a hole in the ice on the Red Deer River. With all the manure on the ice and the thought of communities downstream getting their drinking water from this same source, environmental groups could have a heyday. Eating snow on vast expanses of land gets away from these types of environmental concerns.
It was once thought the energy to melt the snow could decrease feed efficiency by taking too much energy to melt. This has since been disproven especially if the livestock must walk a long way to the thawed water source. That takes energy as well. The heat created in the rumen during the digestion process easily melts the snow.
Overall there are no detrimental health aspects to withholding liquid water from cattle or bison for long periods during the winter. You only must make sure there is adequate fresh snow. Close to calving fresh water should be given as the demands on colostrum and milking necessitate water being readily available. This may prove to be convenient and a cost-effective method for your operation.