Good rumen development can occur as early as three weeks of age. Although weaning at that age is not usually recommended — four or five weeks is a more reasonable goal — it can be done given good management.

“Age at weaning is dictated by management,” says Jud Heinrichs, professor of dairy science at PennStateUniversity. Your management needs to be up-to-speed in three key areas before you can begin an early-weaning program.

Judge how you’re doing in each of these three key areas to find out if your management is up to the challenge of weaning at four or five weeks of age.

Be a rumen manager
“When I look at a baby calf, I’m thinking about growing a rumen,” Heinrichs says.

Does your pre-weaning management program mirror that mind-set?

The nutritional tools are available to help calves prepare for early weaning. The quality of calf starter grain and milk replacer is better than ever, and improvements continue. These factors have “changed the ballgame for us,” making it possible to wean calves before eight weeks of age, Heinrichs says.

Combine these tools with rumen-minded management, and you lay the foundation for a successful early-weaning program.


No calf -is ready for weaning unless she meets the golden rule of weaning. That is, she should be eating 1.5 to 2 pounds of starter per day for two to three consecutive days before you wean her and move her into a group pen.

Analyze calf growth and health goals
Early weaning requires intense management of calf development and health.

“It’s like a pressure cooker in a way,” says Jeanne Wormuth of CY Heifer Farm in Elba, N.Y. “You have to be on top of your game.”

You are more likely to succeed with early weaning if you set — and consistently accomplish — your existing goals. Ask yourself how well you are doing at meeting your goals in these three areas:

  • Calf growth rates. What is your current average daily gain? Or, do calves double their birth weight by weaning?
  • Number of sick calves. What is your calf morbidity level?
  • Death loss. What is your calf death loss?

  If you’re not happy with where you’re at, then correct those areas that need improvement before you whittle down your age at weaning. However, if your management is chugging along — calf growth rates are good, you have few sick calves and death losses are low — then early weaning may be right for you.

Assess transition-heifer management
If you wean calves early, yet fail to help them make a smooth transition to the next phase of their development, all of your hard work goes down the drain. Analyze how you currently manage heifers as they transition into a group environment. Try to spot bottlenecks that might set calves back once they leave individual pens.

In an early-weaning program, it’s inevitable that some calves will have to be held back at weaning time. How will you manage those calves, and if you’re cramped on space in the pre-weaned calf area, where will you house them until they are ready to move into group housing?

Some producers maintain a “special-needs” area to accommodate holdovers. Others, like CY Heifer Farm, have added hutches to accommodate holdover calves.

Also consider your transition-heifer housing conditions. Are calves headed to sub-par housing? Do calves repeatedly get sick when you move them into that environment?

Once you’ve identified potential bottlenecks, think about ways to fix them. If that’s not possible, then you might want to reconsider weaning early.

One strategy that may help you offset problems is to keep calves in individual pens for an additional week after weaning. Connie Evers, of Neighborhood Dairy in Freedom, Wis., weans calves at five weeks of age. Calves stay in individual pens for an additional week before moving into small groups of eight calves per group.

Early weaning certainly isn’t for everyone. However, if your management is up to the challenge in these three areas, then you might want to cautiously trim a few weeks off of your calves’ age at weaning.

The rumen is ready
Here’s proof that weaning can begin as early as four weeks of age. The rumen at lower right was taken from a four-week-old calf that was fed milk replacer and starter. Notice the rumen papillae development.

It is nearly identical in development to that of an eight-week-old calf fed milk replacer and starter (at upper left.) Both calves were raised on an accelerated or intensified calf-feeding program.