Taking care of young calves in cold weather
This winter has brought very cold temperatures to Michigan. Calves need extra care in these conditions to stay healthy.
Calves expend energy to keep warm. The thermoneutral zone is defined as the temperature at which the animal’s heat loss equals the heat production. The animal does not have to expend extra energy to control its temperature when in the thermoneutral zone. The thermal neutral zone for a new born calf is 50-78 degrees F. This is affected by many variables including wind, moisture, hair coat and bedding. By one month of age, the calf is able to tolerate more cold and the thermoneutral zone expands to 32-78 F.
Normal milk replacer or milk feeding will not be sufficient to meet the extra energy requirements of young calves to keep warm in extreme temperatures. Researchers at Cornell University have shown that the pounds of milk replacer needed to meet maintenance requirements of a 100 pound calf increases 44 percent when temperatures are 15 F, compared to 50 F. If the temperature drops to 5 F, then the requirement for maintenance increases 55 percent. Ensure that milk is delivered to calves at 105 F degrees. When preparing milk replacer, follow tag instructions to properly mix the milk replacer at the correct temperature. Too hot of water destroys nutrients within the powder, making it indigestible for the calf. Energy intake can be increased by adding an additional feeding of milk or milk replacer. If an additional feeding cannot be done, then increasing the milk feeding size, increasing fat content of the milk or the amount of powder mixed in the same amount of water can help the calf fight the cold. Older calves are able to consume more starter to battle the cold. In addition to providing increased calories via milk, supplying calves with warm water will aid to maintain body temperature and improved hydration for physical development and immune system readiness.
Dry newborn calf coats as soon as possible to prevent drastic heat loss from the calf. This can be done in a calf-dryer box or with towels. Extra bedding will help the calf keep warm and dry. When laying down, the calf’s legs should be buried in the straw. Deep bedding will trap warm air in addition to keeping the calf dry. A quick and easy way to test that your straw pack is dry is to kneel for 20 seconds on the pack. If your knees are wet, it is time to change the bedding or add more. A calf blanket can also be used with deep bedding to give the newborn calf extra protection. Be sure that the calves are not sweating underneath the coat resulting in wet hair and being chilled as temperatures drop.
Don't forget to provide fresh air while minimizing drafts for young calves. If a young animal is sick, do not withhold milk or milk replacer. The energy from the milk is essential for the calf to fight illness. Electrolytes that provide minerals, energy and protein to the calf should be fed in addition to normal milk feeding for scouring calves. When using electrolytes, do so at least two hours after the calf was given milk. If electrolytes are fed too soon after milk feeding, then the ingredients in the electrolytes can interfere with the clot formation in the abomasum, possibly making the scours worse.