Due to the lack of country-specific data, the so-called IPCC default values are often taken for calculating greenhouse gas budgets. The default value to be applied for Switzerland for the ultimate methane (CH4) production capacity (B0) of slurry amounts to 240 l CH4/kg volatile solids (VS). In the present study, slurry from 64 dairy farms representing all major Swiss milk producing Cantons was collected. Sampling took place both in winter and summer on farms feeding either silage or no silage (two major Swiss dairy cattle feeding systems). Farms were further classified by their annual milk yield. B0 was determined by incubating the slurry at 35 °C for 14 weeks. Winter slurry resulted in a B0 ranging between 241 and 314 l CH4/kg VS, summer slurry B0 ranged between 35 and 62 l CH4/kg VS. This low B0 could have resulted from previous fermentation in the slurry ponds or strong dilution through precipitation. Annual milk yield and feeding system did not influence B0, even though nutrient composition of diets and VS differed significantly. The results indicate that further differences in feeding and slurry management have to be considered in developing countryspecific data.
Livestock can convert grassland and by-products into valuable food. But how many animals would Switzerland need if arable land were primarily used for food production instead of animal feed?
Which stakeholders in the dairy sector have an influence on the productive life of dairy cows? Research results from FiBL and Agroscope suggest that broad-based cooperation is needed to create structures for a longer productive life.
Agriculture is aiming to reduce greenhouse gas and ammonia emissions. Agroscope showed that for dairy cattle housing, feed composition plays a role in these emissions as well as wind and temperature.