Through this and other research, however, scientists know that calves can be weaned as early as 90 days, Jaeger said, but added that an optimum age for a beef production system has not been established.

“The optimum age in response to drought conditions is usually dictated by the severity of the drought and forage availability,” he said. “I usually advise producers interested in early weaning to wean when calves average 120 days of age. Most progressive producers have a 60-day breeding season, so calves weaned at an average of 120 days of age will range from 90 to 150 days of age.”

The studies indicated that the younger calves need feed that is highly palatable, meaning that it tastes good to them, and relatively high in nutrient density to offset the fact that they don’t eat as much as older calves do. They also found that feed moisture content of 20 to 30 percent is optimum.

“Familiar feeds may not have the nutrient density that you’ll need if you wean calves early,” Olson said. Just like humans sorting their most and least favorite foods on a plate, calves will sort their diet ingredients, so the size of the particles matters.