It may not matter, but you would need to do some training and management before weaning. First, work with your veterinarian on a health program. Second, before weaning, expose calves to feed. We know that the sooner calves consume feed after weaning, the lower the morbidity and mortality. This may mean that two to three weeks before weaning, you start calves on a creep feed or offer cows a couple of pounds of cubes three to four times a week. Calves will learn to eat alongside their mothers. Then when they are weaned, consider starting them on a pelleted ration for the first 14 to 21 days. Instead of weaning the calves to a dusty lot, maybe fenceline-wean the calves in a pasture. Train the cows and calves to an electric fence, and have the fence separating two adjacent pastures. Have enough straight fenceline that, when separated, calves can stand across the electric fence from their dams. The first day, calves and cows will stay at the fence; after four days, they both will be content in their pastures. Continue to feed the calves or have the creep feeders available for them. You might want a "baby-sitter" cow to remain with the calves for two to three weeks.
Research has demonstrated that fenceline weaning reduces sickness and death loss in calves weaned at more conventional ages (about seven months of age). Although no data are available on fenceline weaning in early-weaned calves, the principle is the same, and likely the stress on the calves will be less.
