Now heifers must not only be fed to support normal body and calf growth during winter, but also to replace lost fat.
Lost fat concerns Sexten. That energy source affects vigor of the calf at birth. Also, adequate body fat adds quality and quantity to milk the heifer provides her newborn calf.
Nutrition in that first 24 hours determines if a calf thrives, Sexten says. Spring-born calves come into a cold world. They need the rich energy and antibodies provided by colostrum, the first milk, to survive.
Adding one point to body condition score requires adding 100 pounds of fat to the mother's body. That requires adding a pound of gain a day for the next 90 days for a March 1 calving.
If a herd is bred to calve Feb. 1, urgency increases.
In normal years, average hay maintains an average beef cow. The hay has protein and energy to maintain body condition and grow a calf.
A gestating cow needs hay with 10 percent protein. A lactating cow, nursing a calf, requires 12 percent protein.
"The only way to know hay's nutrient content is with a forage test," Sexten says. "Marginal hay requires supplementation."
For many, that supplement means almost 4 pounds of corn gluten feed on top of the hay. Often, that means buying a grain supplement. "You can pay now, or you pay later," Sexten says. The choice comes down to buying feed now or risk the cow not rebreeding.
Sexten urges herd owners to consider risks of not feeding. If a heifer loses her calf, a $2,000 replacement heifer becomes worth $900 in salvage value.
A heifer in poor body condition after calving likely will not rebreed to calve the second year. That happens often, causing huge losses for beef herd owners. A lost heifer must be replaced.
Loss of a calf or heifer puts hay and grain prices in new perspective.
Sexten points out that body condition scoring is explained on page 7 of the Redbook. That herd-owner pocket calendar from the National Cattlemen's Beef Association also provides space to record calves born, day by day.