Submitted to: Agronomy Journal
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/5/2005
Publication Date: 2/7/2006
Citation: Labreveux, M., Sanderson, M.A., Hall, M.H. 2006. Nutritive value of herbage at variable grazing frequencies and intensities. Agronomy Journal. 98:231-237. Interpretive Summary: Maintaining acceptable forage productivity and quality during the grazing season can sometimes be difficult, particularly in areas where cool-season pasture species are predominantly grown. A solution may be in the use of alternative forage species and varieties to increase forage production during the summer. Crops such as chicory and English plantain are being considered for this purpose. We assessed how grazing strategies influenced the nutritive value of chicory and plantain in a three-year grazing study. Chicory and plantain varieties had acceptable nutritive value similar to that of Pennlate orchardgrass. We also found that our recommendations to use a plant-based grazing strategy to maximize yield and persistence of Puna chicory and Lancelot plantain, do not compromise their nutritive value. The reproductive development of chicory and plantain did not limit the nutritive value of the forage produced when the pastures are grazed aggressively during the spring.
Technical Abstract: The use of forage chicory (Cichorium intybus L.) and English plantain (Plantago lanceolata L.) in the NE USA may help forage productivity during summer grazing. However, their reproductive habit may negatively affect the nutritive value of pure stand pastures. We evaluated several cultivars of chicory and plantain, compared them with 'Pennlate' orchardgrass (Dactylis glomerata L.), and determined how different grazing strategies influenced their nutritive value in two grazing experiments during 3 years. Green leaves and reproductive stems from pre-grazing herbage samples were dried and analyzed for crude protein (CP), neutral detergent fiber (NDF) content, and in vitro true digestibility of dry matter (IVTDMD). In Exp.1 and 2, average CP content of all entries was 180 to 200 g kg-1, but generally not significantly higher than orchardgrass; whereas their NDF content was 300 to 400 g kg-1, and always lower than orchardgrass. The IVTDMD of chicory cultivars in both experiments was between 850 - 950 g kg-1; Forage Feast and Puna chicory had higher IVTDMD than Pennlate orchardgrass (on average 866 g kg-1). Low IVTDMD was observed for Lancelot plantain compared to orchardgrass. Nutritive value was affected by the frequency of grazing. In Exp. 2, herbage composition differed significantly among seasons and cultivars; however, the reproductive development of chicory did not limit the nutritive value of the forage produced.