By Blake Jackson
Maintenance energy needs for beef cows increase as temperatures drop. For every 1°F below 32°F, energy requirements rise by about 1%. In the last third of pregnancy, a beef cow typically requires around 11 megacalories per day for maintenance.
On a dry, calm day at 22°F, this increases by roughly 10%, which equals an extra 1.1 megacalories about one pound of corn or two pounds of orchard grass hay.
Wind chill further affects energy needs. The standard method is to adjust feed energy based on the wind chill temperature using 32°F as the reference. For instance, if the wind chill is 0°F, a cow would need 32% more energy to maintain body temperature, equivalent to roughly three pounds of corn or five to six pounds of orchard grass hay.
Wet conditions are the most critical, as moisture reduces the insulating properties of hair and hide. When cattle are wet, 59°F is used as the baseline, with energy needs increasing by 2% for every degree below this point.
For example, if wet cows experience a wind chill of 9°F, their energy requirement doubles, requiring an additional 20 pounds of corn or 40 pounds of orchard grass hay per day. Most cows cannot eat enough under these conditions, leading to body condition loss.
Providing shelter or windbreaks is both economically and practically beneficial. Protecting cows from wind and moisture helps maintain body condition, reduces feed costs, and represents sound animal husbandry practices.
Photo Credit: gettyimages-erdinhasdemir
Categories: Pennsylvania, Livestock, Beef Cattle