1a.Objectives (from AD-416)
The objectives of this cooperative research project are: . 1)Evaluate the relative livestock performance when grazing mixtures of pasture grasses and legumes; and. 2)Evaluate the productivity of grass and legume mixtures; and. 3)Breed pasture grasses and legumes with enhanced compatibility for use in grazing.
1b.Approach (from AD-416)
This research is an expansion and continuation of the research goals and objectives originally started under SCA #58-5428-4-373 entitled "Develop and evaluate plants for improved livestock performance." The new research will determine livestock performance and pasture productivity of grass-legume mixtures in comparison to commercially fertilized grass monocultures. Standard check cultivars and germplasm from ongoing ARS breeding programs will be established in large and small scale research plots. Large scale plots will be used to compare/determine animal performance, carrying capacity, and nutritional content of grass monocultures versus grass and legume mixtures. Results will be based upon livestock weight gain, forage dry matter production, and in-vitro forage quality analyses. Small plots, using multiple species of grasses and legumes in varying composition ratios, will be established to determine optimum grass-legume mixtures and plant densities that maximize pasture productivity in comparison to commercial fertilizer. Livestock grazing on these plots will ensure realistic pressures common to pastures. The role that endophyte infection of grasses has on grass-legume mixture compatibility may be evaluated. Livestock and plant data will be utilized in plant improvement programs to breed for improved compatibility among pasture grasses and legumes.
During FY-10, an experiment to evaluate grass-legume mixtures was initiated. Large paddocks containing tall fescue with or without fertilizer, tall fescue mixed with birdsfoot trefoil, and tall fescue mixed with alfalfa were established. Steers began grazing these paddocks in the spring and preliminary data showed that they gained approximately 3 lbs per day. At this point no differences among legumes have been observed. This research will continue next year. ADODR monitoring activities to evaluate research progress included conference calls, meetings with the cooperator's personnel, and site visits to field plot locations.