Don’t let the unseasonably nice weather permit you to ease up on calf care. It is still winter, and newborn calves need more than 4 quarts of milk during winter months.

Calves are very susceptible to cold stress. This is especially true for calves during the first three to four weeks of age before they consume measurable quantities of calf starter grain.

The environment has a significant impact on maintenance requirements. During the winter, calves require deep, dry bedding to help them maintain their hair coat’s insulating capabilities. A wet environment with limited bedding greatly enhances heat loss.

Calves are born with relatively low reserves of body fat that they mobilize during periods of low energy intake or environmental stress. Cold weather has a big impact on nutrient requirements for a 100-pound calf. For example:

  • At 68 F, feeding 1 gallon of a milk replacer with 20 percent fat provides enough energy for about 0.5 pound of daily gain.
  • When the temperature drops to 41 F, 4 quarts of milk replacer is just enough to meet their maintenance requirements with nothing left for growth.
  • If the milk replacer has only 15 percent fat, 4 quarts of milk replacer is only sufficient for maintenance at 50 F.

Dairy animals are small, with thin skin and a light hair coat, so they lose body heat more quickly than larger animals. The smaller the calf, the more important this relationship becomes. Virginia Tech research revealed that small calves, such as Jerseys, have a maintenance requirement that is at least 15 percent higher than large-breed calves such as Holsteins.

The length of time between feedings can be another stressor because most calves are fed equal amounts in the morning and again later in the afternoon. As a result, calves face nutritional stress during the long evening interval between feedings when the temperature drops at night. Calf feeding rates need to be increased during the winter. A 20 percent fat milk replacer is highly recommended versus those with lower fat content.