Theme 2-2: Forage Production and Utilization--Poster Sessions
Description
Natural and semi-natural grasslands represent an attractive forage source for cows in organic dairy farming. Throughout the grazing season, however, diverse factors such as climatic conditions, botanical composition, as well as grazing and herd management, can influence growth and nutritive value of forage on grasslands. We aimed at investigating the influence of seasonality and grazing management in forage growth and nutritional quality in seven commercial organic dairy cattle farms during the grazing season 2019 in South Germany. Therefore, forty exclusion cages (1 m2) were installed on pastures, which were under three different grazing systems: rotational, short-grass, and continuous grazing. Pasture herbage within and outside the cages was harvested every 4-6 weeks. The botanical composition of the pasture vegetation was estimated by visual observation, its sward height measured by a rising plate meter, and the aboveground biomass accumulation determined gravimetrically. Besides, air temperature and relative humidity were monitored by climate logger. Pasture samples inside and outside the cages were measured for dry matter (DM) according to the Association of German Agricultural Analytic and Research Institutes (VDLUFA) methods. Crude protein (CP), neutral-detergent (NDF), and acid-detergent (ADF) fibre of the samples were determined by near-infrared spectroscopy (NIRS).
The forage biomass yield reached the growth peak in the second sampling (30.4 dt DM/ha) after 52 days. The CP concentrations outside the cages were greatest in late summer (166 g/ kg DM). While the ADF content outside the cages were greatest at the beginning of the grazing season (274 g/ kg DM). Besides, the CP content of the pastures was greatest under the short-grass system (193 g/kg DM) compared to the others systems. In conclusion, the seasonality influences the nutritional characteristics of the herbage, as well as the grazing management. However, the grazing management is influenced by other factors that are difficult to statistically measure.
Included in
Seasonality and Grazing Management Effect on Growth and Nutritional Composition of Herbage on Semi-Natural Grasslands Grazed by Dairy Cows in Southwest Germany
Natural and semi-natural grasslands represent an attractive forage source for cows in organic dairy farming. Throughout the grazing season, however, diverse factors such as climatic conditions, botanical composition, as well as grazing and herd management, can influence growth and nutritive value of forage on grasslands. We aimed at investigating the influence of seasonality and grazing management in forage growth and nutritional quality in seven commercial organic dairy cattle farms during the grazing season 2019 in South Germany. Therefore, forty exclusion cages (1 m2) were installed on pastures, which were under three different grazing systems: rotational, short-grass, and continuous grazing. Pasture herbage within and outside the cages was harvested every 4-6 weeks. The botanical composition of the pasture vegetation was estimated by visual observation, its sward height measured by a rising plate meter, and the aboveground biomass accumulation determined gravimetrically. Besides, air temperature and relative humidity were monitored by climate logger. Pasture samples inside and outside the cages were measured for dry matter (DM) according to the Association of German Agricultural Analytic and Research Institutes (VDLUFA) methods. Crude protein (CP), neutral-detergent (NDF), and acid-detergent (ADF) fibre of the samples were determined by near-infrared spectroscopy (NIRS).
The forage biomass yield reached the growth peak in the second sampling (30.4 dt DM/ha) after 52 days. The CP concentrations outside the cages were greatest in late summer (166 g/ kg DM). While the ADF content outside the cages were greatest at the beginning of the grazing season (274 g/ kg DM). Besides, the CP content of the pastures was greatest under the short-grass system (193 g/kg DM) compared to the others systems. In conclusion, the seasonality influences the nutritional characteristics of the herbage, as well as the grazing management. However, the grazing management is influenced by other factors that are difficult to statistically measure.
