As the days grow shorter and winter sets in it is a good time to review some items for management of cold stress and general cattle comfort. Other than the bos indicus or Brahman breeds most cattle have a remarkable ability to tolerate the harsh winter climate of the upper Midwest and Northern Plains. Their winter hair coat provides a layer of insulation, as does the internal fat that comes with good body condition. There are some manageable conditions that can remove the effectiveness of this ability, rob performance and create stress in the animal, however. One of these factors is wind. Just as with humans, cattle are subject to the combination of temperature and wind speed. Wind chill can negate some of the insulation value of the heavy winter hair coat that helps protect cattle from cold weather. The use of windbreak fences or shelter allows cattle to find a microclimate within where wind speed, and therefore wind chill, is reduced.
Another environmental factor that can reduce the insulation value of a heavy winter hair coat is moisture. A wet or muddy hair coat can increase the cold stress by almost 40 degrees when compared to cattle with a heavy winter hair coat. In open feedlots, good mound construction, establishment of high and dry traffic patterns and timely snow removal can help keep cattle dry and comfortable. Many feeders have constructed deep-bedded confinement housing in recent years. These hoop or mono-slope structures provide wind protection in the form of shelter. The key to winter animal comfort in these facilities is bedding management. Proper bedding management is affected by temperature, humidity and pen density. Average bedding use in these systems is about 4-5 pounds per day.
Beef cows that are allowed access to natural windbreaks, such as a grove of trees, have an ability to seek out the most comfortable microclimate in harsh conditions. We encourage producers to use good judgment when establishing winter feeding areas if those locations tend to be near a creek or river. While winter feeding locations for beef cows that are vegetated may not be considered a “feedlot” by regulatory definitions, it is still good environmental practice to maintain feeding areas where manure cannot be washed into water sources.
Source: Dan Loy, Iowa Beef Center Director