Fatty acid profiles of orchardgrass, tall fescue, perennial ryegrass, and alfalfa
Recent research shows that the meat from beef animals finished on pasture has greater concentrations of omega-3 fatty acid (FA) and conjugated linoleic acids (CLA) compared with animals finished on high-concentrate diets. However, little is known about the FA concentrations in forage that might alter these FA in the meat of pasture-finished beef. The objective was to determine the FA variation between and within forage species commonly grown in pastures in the Midwest. A secondary objective was to identify phenotypic characteristics that may be associated with individual FA. The forages analyzed included multiple cultivars of orchardgrass (Dactylis glomerata L.), tall fescue [Lolium arundinaceum (Schreb.) S.J. Darbyshire = Schedonorus phoenix (Scop.) Holub], perennial ryegrass (Lolium perenne L.), and alfalfa [Medicago sativa L. ssp. sativa and falcata (L.) Arcang.]. Grasses had higher amounts of -linolenic (C18:3) acid compared with alfalfa. Conversely, alfalfa had larger amounts of linoleic acid (C18:2) than did the grasses. Correlations between phenotypic traits and specific FA were found; plant total chlorophyll had the greatest correlation to total FA concentration. Overall, there is not a large amount of within-species variation that breeders could use to make large changes in FA concentrations.