We are learning more about the feeding behavior of dairy animals housed indoors. Among the obvious conclusions:

  • Cows are motivated to eat when fresh feed is delivered to the feed bunk.
  • Cows will often sort through a TMR for the grain component.

But what if there is an unexpected variation in energy density in the TMR delivered to the bunk? What effect will that have on the feeding behavior of heifers?

In a recent experiment, researchers at the University of British Columbia put 32 heifers into four groups of eight. The groups were exposed to three different TMRs — low-energy, moderate-energy or high-energy — in different feeding stations at different points in time. When heifers were exposed to a higher-energy, higher-quality ration than the one they had previously experienced, they spent more time at feeding station and were less likely to change to another feeding station. This provides insight into the strategies cattle use to learn about their environment, the researchers say in the January 2013 edition of the Journal of Dairy Science.

“A key finding of this study was that competitive interactions increase when TMR quality is non-uniform across the feed bunk, reflecting the motivation of individual heifers for obtaining access to the higher-quality feed,” they said.

Consistency in feed bunk management will help reduce competitive interactions and ultimately help ensure that the animals in a group have similar opportunities to obtain access to the intended diet, they add. Read the abstract.