Up until now we have had some fairly temperate weather this winter.
Cows lose their acclimation to cold when we have a periods of nice weather, increasing the impact of cold temperatures. The cow’s fleshiness and hair coat have a big impact on their tolerance to colder conditions.
Cows in good body condition, having body condition scores of 5 to 6, with good thick winter hair coats have a “lower critical temperature” of around 32 F. Thin cows with sparse hair coat are at more risk with lower critical temperatures of around 40 F, while cows with wet haircoat have lower critical temperature of 59 F.
For each degree below the lower critical temperature energy requirements increase by 1%. When we have wind chills that get to 0 F, maintenance energy requirements will increase by up to 30 to 40%.
Here are some things to consider for winter weather:
• Make sure cattle have access to as much hay as they want to eat.
• Ruminal fermentation helps keep the animals warm.
• If increasing supplementation rates to help offset energy deficiencies it is best to feed supplements every day.
• Feed cattle beside or in a grove of trees or some other windbreak that is large enough for all the animals to gather. The better the windbreak, the lower the animal’s cold stress.
• If there is no natural or constructed windbreak available near a water source, a quick and simple one can be made by placing a line of round bales of straw or low-quality hay where cattle can bed down.
• Ensure cattle have unrestricted access to unfrozen water. If water intake is limited, hay intake is reduced and ruminal fermentation is affected.
• Feed cattle relatively close to their water source. The farther away the water source, the longer they will wait to get a drink.
• Unrolling low-quality hay as bedding will help provide relief from the extreme temperatures. — Paul Beck, Oklahoma State University Extension beef cattle nutrition specialist
