Full grazing or indoor feeding of fresh herbage and partial grazing are common feeding systems for dairy cows in Switzerland. Project Hohenrain II investigated a comparison of three different grassland-based milk production systems, a partial grazing with indoor feeding of fresh grass with reduced and increased concentrate supplementation was compared with the full grazing system with seasonal calving and no concentrate supplementation during three years. In the years 2014 and 2015, herbage from pastures and for fresh indoor feeding were regularly taken during the growing periods and the minerals calcium (Ca), phosphorus (P), magnesium (Mg), potassium (K), sodium (Na), copper ( Cu), iron (Fe), manganese (Mn) and zinc (Zn) were analysed. Herbage from pastures had significantly lower Ca and higher P, K, Cu and Zn contents than herbage for fresh indoor feeding. This is mainly due to the different stages of development of the herbage. No significant differences were determined in the Mg content. Apart from the sodium content, the mineral contents varied significantly in the herbage during the growing periods. With the feeding of herbage, the needs of a dairy cow up to a milk yield of 30 kg per day could be covered by Ca, P, K, Cu, Fe and Mn. On the other hand, this was not the case for Mg, Na and Zn.
Mineral content of herbage