Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Animal Science

First Advisor

Benoit St-Pierre


Ruminants and the microorganisms within their rumen have an intricate symbiotic relationship. Ruminants are able to convert plant materials that are indigestible to humans into meat, milk, and fiber for human consumption and use. Supplementing lipids in diets fed to beef cattle could be beneficial for the host animal as lipids are a higher density energy source. However, they can be detrimental to rumen microorganisms. While much research has been involved in elucidating the composition of the ruminal microbiome, knowledge of the effects of lipids on the ruminal microbiome has been quite limited. In this context, we took advantage of an animal study performed by a collaborator to investigate the effects of lipids on the rumen microbiome. In the original study, a Latin Square design was used to test five experimental diets with five steers. The five experimental diets consisted of a control diet with no extra added lipids, and four diets with either tallow or linseed oil added at either 4% inclusion or 8% inclusion. Representative rumen samples were collected from each steer after each diet to perform bacterial composition analysis. A total of 28 predominant OTUs were identified. In an effort to further investigate the effects of lipids on the rumen microbiome, a metagenomics approach was used to create contigs corresponding to the bacterial chromosome of OTU CH5-00046, which was one of the most abundant OTUs identified in this study. Gene annotation revealed the presence of enzymes involved in lipid metabolism as well as a pathway responsible for the production of butyrate.

Library of Congress Subject Headings

Beef cattle -- Feeding and feeds.
Rumen -- Microbiology.
Lipids -- Metabolism.

Number of Pages



South Dakota State University

Included in

Beef Science Commons