Research Note

Calf to Heifer ASAP:

What an Automated Feeding System Reveals

With the U.S. heifer-to-milk cow ratio at the lowest point in more than 25 years, dairy producers want to speed calf growth without reducing replacement heifer quality. How to make it happen?

Research shows that high early age growth rate generally correlates with:

• Younger age at first calving
• Increased lifetime milk production
• Reduction in overall raising costs

Although numerous health, environment, and other factors influence calf growth rate, nutrition is key, so accelerated feeding programs (AFP) usually target increasing body weight (BW) through greater intake of higher protein diets.

While a conventional feeding program provides a calf milk or milk replacer at around 10% of BW, AFP allow the calf to consume greater amounts in the preweaning phase with more protein in the milk replacer (up to 30% CP). Commercial scale AFP depend on automated feeding systems that identify each calf and provide data on her feeding behavior.

Boerman pointed to a recent study that used data covering several years on a single northern Indiana farm with eight calf autofeeders in order to generate predictive equations for future BW of heifers. The researchers reported a 263-kg difference in predicted BW at 400 days from the lightest to the heaviest heifer present in the data set. Disease incidence and other variables collected during the first 60 days of life accounted for over 30% of the difference in BW up to 400 days of age.

Using data from the same farm, another study reported that increased treatment for respiratory disease from 61 to 120 days significantly reduced heifer survivability to first lactation as well as chance of pregnancy. Calf and heifer growth data also helped predict first lactation performance.