Cattle Health: Managing cold stress
At the time of this writing, this article may seem premature with open weather and mild temperatures in Iowa. However, at some point this winter, we will have to deal with cold stress and how to manage it.
If you don’t remember anything else, remember this: A clean and dry hair coat is essential for the animal to maintain body heat. With most winter hair coats, there are longer guard hairs. These keep snow from reaching the denser undercoat that insulates the skin and muscle.
If moisture reaches the skin in the winter, the animal will lose body heat. Likewise, if the hair becomes matted with mud or manure, body heat will be lost. This is why a clean, dry area is essential for the animal. Providing bedding is a good way to help keep the animal dry and warmer. Both oat straw and corn stover are common bedding materials that have good absorbency.
In a North Dakota trial, researchers looked at the effect of the amount of bedding (wheat straw) on the winter performance of open feedlot cattle. Bedding treatments were none, modest amount (385 pounds per animal) and generous amount (674 pounds per animal). Bedding increased average daily gain, dressing percent and percentage of carcasses grading Choice. All are good reasons to provide bedding.
Another way to increase warmth is to provide a windbreak. An 80% solid fence (or 20% open space) reduces wind speeds for a greater distance and spreads the snow out for faster melting. A minimum height of 10 feet for this fence is recommended for better wind control. Windbreaks can be constructed with wood, metal, or forage bales.
And don’t forget the importance of nutrition. Access to clean, fresh, unfrozen water is essential for dry matter intake. As a rough rule, plan on approximately one gallon of water for every 100 pounds body weight of the animal. Increased heat production by the animal during cold stress also requires increased energy in the diet. The energy needs of the beef animal increase 1% for every degree below 32° for a beef animal with a normal winter hair coat.
Think of what you prefer in winter weather. Good housing, a nice winter coat, and plenty of food and drink sound pretty good. Your cattle deserve the same!
Source: Beth Doran, ISU Extension beef program specialist