Nutzbarkeit von NIRS zur TS- und Proteingehaltserfassung bei frischem Luzernegras

Livestock wellbeing and output are dependent on the feed and its composition. But yields as well as product quality are varying because of heterogenous sites. Therefore, it is favorable to know quality parameters of forage. Near-infrared spectroscopy (NIRS) is a cost-effective and fast analysis method. It is already available for different scopes in agriculture, but there is a lack for fresh, not wilted material e.g., on grazing land. In 2024, NIRS models of the VDLUFA were tested on two alfalfa-grass sites near Kassel, Germany, in comparison with Dumas-analysis for protein content and laboratory DM (dry matter) measurement. NIRS achieved good results for DM with RMSE up to 2 % DM, but there was no sufficient heterogeneity and correlation to divide the field into DM-zones. Protein contents differed much more within the field, but the R² of NIRS compared to Dumas only reached a maximum of 0.346 and very much underestimated the protein content.