Effect of continuous grazing on forage quality, quantity and animal performance

The effects of different grazing intensities of heifers on sward parameters such as sward structure, plant species diversity, herbage growth and forage quality as well as individual live-weight gains and live-weight gains per pasture area were studied in an upland area in the northern part of the Czech Republic over 4 years (1998–2001). The sward was maintained at a target height of 5 and 10 cm under intensive (IG) and extensive (EG) grazing, respectively. The total biomass production was higher under the IG than the EG treatment. In the Czech upland conditions, double peak curves of biomass growth during the grazing season were more typical than curves with one high spring peak. Species that responded positively to both treatments were the predominately short growing Trifolium repens, Taraxacum spp., Veronica arvensis and Agrostis capillaris. Tall species like Senecio ovatus, Alopecurus pratensis, Elytrigia repens and Aegopodium podagraria were associated with unmanaged plots. Total crude protein contents and forage digestibility were higher under IG. The content of crude fibre showed a reverse effect. Seasonal live-weight output per hectare under IG was approximately 1.5 times higher than EG treatment. However, if state subsidies are included, EG can be more profitable under the current Czech conditions than IG and satisfies both farmers and nature conservation objectives.