Q. How do cattle nutrition requirements change during extended periods of cold weather? What things can be done to help reduce stress to cattle when conditions are bitter cold or stormy?
A. Cattle typically have a lower temperature comfort level at around 20° to 30° Fahrenheit under dry, still conditions. When air temperature or wind chill drops below this threshold then cattle begin to need more energy from feed or use their own fat reserves in order to maintain body temperature. Beef cattle in a Body Condition Score of 5 or higher will be able to handle cold stress better than thin cows as they have fat reserves to help insulate them from the cold and can also use that fat as an energy source.
A rule of thumb is that for every 1° Fahrenheit the average daily temperature is below 30° a cow with a dry hair coat in a moderate body condition will have their average energy requirements go up 1%. Wind chill and wet conditions can drastically increase these requirements. Cattle with wet hair coats under windy conditions may not be able to produce enough body heat to stay warm.
Windbreaks can significantly help to reduce weather stress. Also, having a dry place for cattle to lie down can help ease cold stress. For cattle in a dry lot or feedlot environment under extreme cold conditions for an extended time, bedding such as cornstalks or wheat straw can aid to reduce the stress of having cattle lay on frozen ground.
If additional supplemental feeds are needed to help meet nutrient requirements for beef cows on roughage diets in cold weather, consider using feedstuffs which are high in digestible fiber and energy dense. Distillers grains and soy hulls would be two examples of such feeds.
Dr. Rick Rasby recorded a webinar Caring for Cattle in Cold Weather that provides additional information on management practices to consider when cattle are under cold stress.
Aaron Berger, Extension Educator
Panhandle Research & Extension Center
University of Nebraska