Calf rearing is a cornerstone of dairy farming, and early life management significantly impacts long-term health and productivity. The primary goals in a calf’s early weeks are developing a robust immune system and promoting rumen development. Achieving these objectives allows for stress-free weaning by six weeks of age or earlier—a practice that brings both economic and animal health benefits.
According to a USDA survey, over 58% of producers wean calves between six to eight weeks, while 15% delay weaning until 12 weeks or later. Early weaning reduces feed and labor costs, minimizes digestive issues, and improves the calf’s ability to digest cost-effective concentrates and forages. When managed properly, calves can be safely weaned at four weeks of age.
Rumen Development and Feeding Practices
At birth, a calf’s rumen is underdeveloped. Dry feed intake, particularly grains, promotes rumen growth by producing volatile fatty acids essential for development. In contrast, feeding hay too early can slow rumen development and calf growth due to its bulkier nature and lower energy density.
To optimize early weaning, producers should:
- Offer high-quality calf starter from three days of age, ensuring it is fresh to encourage intake.
- Provide fresh, clean water starting at one week of age, which is crucial for improving starter intake.
- Wean calves when they consistently consume 0.7 kg of starter daily for two consecutive days, typically around four to six weeks of age.
- Introduce forages only after six weeks of age when the calf consumes over 0.9 kg of grain daily, avoiding silages and pastures due to high moisture content.
The University of Manitoba dairy calf program, for instance, weans calves at five weeks and incorporates limited forage—0.25 kg of chopped hay daily—starting at four weeks. Forages are gradually increased post-weaning.
Balancing Forage in Preweaning Diets
Feeding hay before weaning is a debated topic. While some programs include limited hay to aid transition, others avoid it entirely to focus on rumen-stimulating concentrates. The key is aligning feeding practices with the goal of early weaning while maintaining calf health and growth.
By adopting these practices, dairy producers can streamline calf-rearing programs, optimize growth, and achieve sustainable early weaning.
