Thee relation between stocking rate, supplementary feed and grazing hours on grass intake as assessed by model simulations

摘要

The number of grazing cows is decreasing in several countries in Europe. Farmers sometimes have problems finding the right grazing system suitable for their farm, especially in situations with restricted grazing, and therefore make the choice to keepthe herd inside. Guidelines will help farmers to choose the right grazing system and the right number of grazing hours adapted to the amount of supplementary feed and the stocking density. To optimise grassland management, farmers need predictions of grass intake under a range of supplementary silage feeding and stocking densities. Based on model calculations with the whole farm model DairyWisc, a table with an overview of grass intake was created for different stocking densities and different amounts of supplementary silage feeding in the Netherlands. The model used a mowing percentage of 200% (the total grazing area was mown twice a year for silage) to realise enough aftermath. The supplementary feeding was based on a TMR with 50% silage maize and 50% silage grass. The table is applicable for an average herd (including primiparous and multiparous dairy cows) with an average annual milk production of about 8,500 kg cow"1 and gives a quick overview of the grazing possibilities.