Forage botanical and chemical composition on dairy farms with different grassland systems and production systems

Summary

Thirty-two dairy farms in Middle-Norway with different grassland systems (short-term (<4 years) grassland (S) or long-term (>7 years) grassland (L)) and different production systems (organic (O) or conventional (C)) were compared in a field study in 2007. In a principal component analysis on variables including farm details, botanical composition and chemical forage composition, the farms were separated into organic and conventional farms with the exception of one farm. Amongst the organic farms most SO farms were distinguished from LO farms. Concentration of forage crude protein was positively correlated with proportion of grass. Concentration of non-fibrous carbohydrates, in vitro digestibility and net energy lactation was positively correlated with proportion of legumes. Species diversity and cutting time at first cut was positively correlated with proportion of non-legume herbs