With cooler weather setting in, remember that calves’ thermo-neutral zone is between 60° and 75°F. Below that, young calves start using their energy to maintain body temperature, limiting energy used for growth. A calf’s energy requirement for maintenance increases 1% for every degree the temperature drops below its thermo-neutral zone. So, for an average daily temperature of 35°F, calves need 25% more energy just for maintenance, let alone growth.

Tom Earleywine, PhD, Land O’Lakes Animal Milk Products, offers these tips for keeping calves healthy and growing during cold weather months:

  • Feed calves a full potential ration; calves fed a “maintenance” diet are more likely to become sick and fall behind on weight gain and growth.
  • Incorporate a third feeding of milk replacer, during the coldest part of the day (yes, that’s usually at night!) to provide extra energy and warm up the calves’ bodies. When calves are up for that extra feeding, they’re more likely to eat more starter, which also keeps them growing.
  • Continue to offer free choice water. Provide warm water with morning and afternoon feedings, and consider adding a noon watering. Keep water and grain buckets clean.
  • If scours hit, primary treatment should be geared toward restoring water balance by feeding electrolytes in a separate feeding at body temperature. Continue feeding calves normal milk replacer levels for energy for maintenance and growth.
  • Provide enough dry bedding for calves to nestle into and keep warm. Straw or chopped corn stalks offer optimal protection for the calf; sand and sawdust are ideal for summer but not winter. Proper bedding depth is if calves’ legs are completely hidden when they’re lying down.

Keeping calves warm, healthy and growing during the cold weather will help ensure they become healthy, well-grown heifers that eventually enter the milking herd as profitable, productive cows.