Effect of different pasture management and fertilization on nutritive value of grassland

The effects of different levels of grazing utilization and mineral fertilization on the feed quality of permanent grasslands within the context of nutrition aspects were studied in the locality Rapotín during the years 2003–2010. The experimental plots of grassland were grazed by cows with three different regimes (four, three or two grazing periods per year). Each treatment was established in two types of fertilization: with or without additional application of mineral fertilizers (N100P30+K60, pure nutrients). The mean results for organic matter digestibility of forage (determined by modified in vitro method Tilley and Terry) ranged from 62.4% (extensive management) to 75.7% (intensive management). In this study and under experimental conditions the best suitable nutrient ratio (PDIN:PDIE = 0.95) was achieved with grassland utilization in three grazing periods per year without mineral fertilization. However, it was proved that suitable nutrition value could also be retained by occasional application of mineral fertilizers. The feed from extensive pastures was characterised by a low nutritive value. Different approaches depending on the site and climatic conditions and the purpose of forage utilisation are fundamental to appropriate grassland management