Calf-feeding programs need to work in concert with the physical environment. Young calves have a thermoneutral zone between 68 F and 82 F, and become cold-stressed at just 50 F. Keeping a calf healthy and growing at temperatures outside of its thermoneutral zone requires feeding adjustments, says Mike Van Amburgh, dairy nutritionist at Cornell University.

For example, a 100-pound calf fed a traditional amount of milk replacer will be close to a negative energy balance at 50 F, and it will be mobilizing adipose (fat) tissue at 32 F.  The chart below shows how much milk and/or milk replacer dry matter would need to be fed in order to meet a 110-pound calf’s energy requirements at varying temperatures. This is assuming dry conditions -— and at this weight, no reliance on starter feed for the energetic difference.

59 F

32 F

5 F

Milk replacer

1.0 lb.

1.35 lbs.

1.77 lbs.

Whole milk

.91 lb.

1.20 lbs.

1.51 lbs.