Beans and rice. Macaroni and cheese. Some foods seem to go together. The same may be true for plants that contain secondary compounds (SC). SCs can limit forage intake and are often viewed as plant defenses. But positive roles of SCs in herbivory have also been recognized during the past 30 years. For example, forage intake may increase when herbivores eat plants that contain biochemically complementary SCs. Thus, it may be possible to design pasture mixes with diverse plant species to increase animal production.

Jake Owens, USU graduate student, is investigating the possibility that certain plant secondary compounds are complementary. Based on their chemistry, there might a complementary relationship between 1) the alkaloids in tall fescue (TF) and saponins in alfalfa (ALF), and 2) the alkaloids in reed canary grass (RC) and the tannins in birdsfoot trefoil (BFT). If so, sheep fed mixtures of the above forages may maintain higher nutrient intake and use nutrients more efficiently than sheep fed only alkaloid-containing forages.

Owens plans to run an intake study, a digestion balance trial and analyze rumen fluid from sheep fed fresh clipped TF alone, TF + ALF, RCG alone and RCG + ALF. A second trial will look at RCG alone, RCG + BFT, TF alone, and TF + ALF. Owen also plans to repeat the above studies using ground diets with added SCs similar to those in the forages mentioned above.

The research will be conducted at Utah State University. Fred Provenza, Professor, and Juan Villalba, Research Assistant Professor, both of the Department of Wildland Resources will oversee the project.