Researchers examine the feed efficiency of pregnant Angus heifers

While cattle production has historically focused on increasing the feed efficiency of steers to produce a marketable beef product, researchers at the University of Tennessee Department of Agriculture are studying the feed efficiency of heifers, whose health and gestation prepare production for success.

The research is led by Phillip Myer, an associate professor in the Department of Animal Science who specializes in the microbiology of the four-chambered stomach of grazing animals. Gabbi Martin, a graduate student in the Department of Animal Sciences, works with Myer. The team is studying the nutritional changes that occur during pregnancy, the impact of these changes on the rumen (stomach) environment and the resulting feed efficiency in Angus heifers. The information will enable beef producers to change strategies to improve the overall sustainability of heifers and their calves.

“Ideally, the cow is a long-term part of a herd and it’s important to study the rumen environment to improve cow-calf company,” says Myer. “This work is important to determine the microbial changes in the rumen that occur in heifers during gestation and their impact on nutrition and feed efficiency.”

It is optimal for producers to have cows that produce efficient calves while maintaining a stable, efficient rumen at all stages of production, including gestation. To achieve this, Myer and his team study the changes that occur in the rumen environment and determine the effects these changes have on the host. This information will improve the sustainability of the cow and calf business.

“I am excited about the current and future impact of this work related to the production and promotion of quality beef for Tennessee producers,” said Martin, a fifth-generation farmer.

Research for the project, titled “Pregnancy Influences on Feed Efficiency and Rumen Environment in Angus Heifers in the Production of a Quality Beef Product,” began in October 2021 and is being conducted at the East Tennessee AgResearch and Education Center near Knoxville and the Plateau AgResearch and Education Center performed in Kreuzville.

Since the beginning of the project, the team has produced a publication in ruminant listing several potential biomarkers of feed efficiency in both low and high feed efficiency heifers. In addition, the research team found correlations between rumen bacteria and metabolites found in rumen fluid. Further publications are to follow.

Provided by the University of Tennessee Department of Agriculture