According to data from the National Animal Health Monitoring System’s Dairy 2007 study, the most popular age for weaning a calf in the US is 8 weeks. The next highly preferred age for weaning are 6, 7, 12 and 10 weeks, respectively.
Without significant analysis, these preferred weaning ages are all even week points with the exception of 7 weeks. Al Kertz, a private dairy nutritionist based in St. Louis, says this is a management decision rather than one tied to the best situation for the calf.
Kertz suggests that the timing of weaning calves should not solely revolve around when your schedule permits it. Weaning is conditional on rumen development. If the rumen is not ready, chances are you are not doing what is best for the calf.
You can assist in the rumen development by introducing small amounts of grain to calves. According to Jud Heinrichs and Coleen Jones of Penn State University, the sooner starch is digested by the calf, the sooner rumen development occurs. Getting them to eat those first few bites of grain can have significant and positive effects.
According to Heinrichs and Jones, “It takes about 21 days to develop the rumen papillae from the initial time that grain is fed. This development time is from when grain is first fed, be it 2 days of age or 20 days of age. This is where management plays a big role in determining rumen development and weaning age.”
DCHA Gold Standards III recommends making a palatable, high-quality calf starter ration available at all times for calves by 1 week of age. It is important that feed is kept fresh and make sure it does not become contaminated.