Impact of grazing practices on farm self-sufficiency, milk and economic performances of three automatized farms

The dairy sector is facing serious economic difficulties linked to low milk price and volatility of feedstuff price. In this context, reducing farm inputs is necessary. Optimization of use of grazed, ensiled or dried grass could be a key strategy to improve self-sufficiency and thus to decrease feeding costs. Yet, practice of grazing is disappearing due to several factors, including increased size of dairy herds and development of automation. However combining grazing and automatic milking systems (AMS) is possible. Three Walloon dairy farms equipped with an AMS were monitored to assess their grazing practices, grass proportion in the cows’ diet both at barn and on pasture and the economic advantages linked to grass use in 2015. These farms practiced various grazing strategies including full-grass system (FG), day and night grass allocation (DNG), and rotational grazing (RG) completed with a partial mixed ration. The effects of grazing on milk yield (MY) were also evaluated. Grazing reduced the daily feeding costs per cow in all systems with variable impact due to grazing management. The most pronounced decline was observed in FG with a severe drop in MY. Conversely, the decrease in MY was less marked in the other farms.