Submitted to: Grassland Science in Europe
Publication Type: Proceedings
Publication Acceptance Date: 6/19/2004
Publication Date: 6/24/2004
Citation: Taube, F., Brzezinski, N., Muller, L.D., Sanderson, M.A., Soder, K.J., Wachendorf, M. 2004. The influence of the vertical structure of grazed mixed swards on diet selection of dairy cows. Grassland Science in Europe. 9:635-637. Interpretive Summary:
Technical Abstract: Diet selection of grazing animals is influenced by the sward composition and the vertical sward structure. A grazing study was established to determine if selective grazing behaviour affects the sward structure among different sward layers. Replicated pastures (1 ha each) were planted including mixtures of two (grass, white clover), and nine temperate forage species (included forage chicory). The vertical structure was measured with special clipboards and divided into six layers and the different plant groups. Forage samples of the different layers were analysed for nutritive value via calibrated near infrared reflectance spectroscopy. Calibration samples were analysed for neutral detergent fiber (NDF), in-vitro true digestibility (IVTD) and crude protein (CP). The measurements were conducted in 4 grazing periods during the grazing season. The nine-species mixture out yielded the two-species mixture. The deep rooting chicory was particularly productive due to the very hot dry weather conditions in the experiment. Cows tended to graze layer by layer. The results of the stratified samples showed more selection behaviour among the top layers than the bottom layers. Cows prefer legume to grass and young chicory leafs to bolted chicory stems. The management of pastures including forage chicory is very demanding, especially during periods when the phenological development of chicory becomes reproductive.