One of the most important issues directly associated with the health of calves is proper ventilation. Ensuring that calf barns and hutches are not completely closed and that calves are housed in a draft-free environment are two key elements to proper ventilation.
As temperatures fall below 50°F, calves deplete their own energy making daily adjustments to calf conditions important.
Source: The Cattle Site, November 21, 2022. Link.