The Effect of Grazing System and Level of Concentrate Protein Feeding on Milk Production and N Use Efficiency of Dairy Cows on Peat Meadows

• Published in: Sustainability 2020-02, Vol.12 (3), p.1055
• Main Authors: Hoekstra, Nyncke, Holshof, Gertjan, Zom, Ronald, Philipsen, Bert, Schils, René, van Eekeren, Nick
• Format: Article
• Language: English
• Subjects: Dairy cattle; Dairy farming; Dairy farms; Dry matter; Efficiency; Farm management; Grasses; Grazing; Herbivores; Meadows; Milk; Milk production; Peat; Proteins; Stocking; Stocking rates; Strip; Sustainability; Urea
• ISSN: 2071-1050; 2071-1050
• DOI: 10.3390/su12031055

The aim of the study was to assess the effect of two contrasting grazing systems, strip-grazing and kurzrasen, at a high stocking rate on herbage intake and milk production and quality on a peat meadow. Additionally, we assessed the effect of the level of crude protein (CP) fed in concentrate on milk production and N use efficiency. Even at the relatively high stocking rates, cows still achieved substantial fresh grass intake (on average >6 kg dry matter cow−1 day−1) from both systems. Despite the lower level of gross grass production under kurzrasen management, the difference in milk production between kurzrasen and strip-grazing was small and non-significant. Feeding concentrate with a lower CP level, had no negative impact on milk yield, provided that the CP content of the total ration remained above ~150 g kg−1 DM and milk urea content was above ~18 mg 100 g−1 milk. Reducing the CP content in the concentrate significantly increased the N use efficiency, and both were strongly related to the milk urea content. Therefore, optimising the use of milk urea as a management tool on dairy farms, also during the grazing season, could reduce N losses to the environment, while maintaining productivity.