Calving season has either started or is just around the corner. First-calf females represent your future brood cows and they require more labor and higher quality feeds. They will reward us by being productive cows for a long time.
One of the challenges is providing a high-quality diet to these females after calving. In many situations, the energy needs are not met and the first-calf female loses weight and body condition from the time of calving to the start of the breeding season. This puts your best herd genetics and future herd member at risk of being culled.
The pounds of protein or energy needed by the first-calf female compared to a mature cow at the same stage of gestation or lactation are not all that different. However, the percent of the diet that needs to be protein or energy between these two groups of females is different. The difference is because of the amount of feed/forage that they can eat. The mature cow can eat more feed compared to the younger female.
For this reason, beginning at least three weeks before calving, heifers need to be managed and fed separate from the mature cows.
Research conducted at the University of Nebraska indicates that a first-calf heifer within three weeks of calving experiences a 17 percent decrease in daily feed intake. These data further illustrate the need to separate first-calf heifers from mature cows beginning at least three weeks before the start of the calving season and illustrate that nutrient density of the diet has to be high because intake is restricted.
Intake is reestablished to more normal levels by about one week post-calving.
The first-calf females post-calving need to consume a diet that is at least 62 percent TDN and 10-11 percent crude protein, depending on level of milk production. Feeding prairie hay that tests 54 percent TDN and 6.5 percent crude protein, bromegrass hay that is 58 percent TDN and 11 percent crude protein, or early-bloom alfalfa that is 60 percent TDN and 20 percent crude will not meet the first-calf female's energy (TDN) needs, whether feeding individually or in a combination of feeds.
Some of these forages will not meet their protein needs. A high energy feed needs to be supplemented. Corn, distiller’s grains, gluten feed, 20 percent cube, or silage may be good choices. Make sure the protein requirement is met, especially when corn or silage is fed.
In pasture situations, the supplement may be fed on the ground instead of in bunks. Depending on the quality of the hay and the energy content of the supplement, it may take 2-3 pounds per head per day to meet requirements. Likely there is minimal waste when feeding an energy cube/cake or whole shell corn.
When supplementing wet distiller’s grains on the ground, it is hard to visually find any left on the ground. A research experiment was conducted, and reported in the 2010 Nebraska Beef Report, to determine difference in performance when cattle were supplemented distillers grains in a bunk or on the ground.