Nutritional steering towards an economical and ecological sustainable dairy farm: focus on methane and nitrogen efficiency (MELKMETAM)
The dairy sector in Flanders faces major challenges in terms of methane emissions (greenhouse gas reduction) and nitrogen excretions (eutrophication/acidification). The aim of this VLAIO LA trajectory was to generate applicable knowledge and solutions to put the dairy industry on the track to lower methane emissions and nitrogen efficiency. The central question is: Which methane-reducing and nitrogen-efficient feed strategies bring the individual Flemish dairy farms towards an ecological and economic optimum? The project led to the formulation of feasible and scientifically based advice about how to cost-effective produce milk with a lower environmental impact.
Researchers on this project worked closely with the dairy industry in Flanders. The researchers determined the environmental and economic impact of methane-reducing and nitrogen efficiency feed strategies on farms. Supplements were first screened for their potential to reduce methane and/or save nitrogen, then the same was done with optimized Flemish rations. This research was carried out in the closed circuit chambers because this environment allows the researchers to estimate all of the greenhouse gas emissions as well as to make a nitrogen balance. The strategies that showed potential were tested under farm conditions in the ILVO research farm or on farms where the methane emissions were measured using GreenFeed equipment (concentrate feeders that can measure methane and CO2). The results include performance parameters, carbon footprint and economic impact of the ration. These were included in knowledge sheets and a tool presented on the SMART melken website (https://www.ilvo.vlaanderen.be/smartmelken)
Studying both types of emissions - methane and nitrogen - at the same time and coupling that research to the existing Flemish rationing habits, is very interesting for the dairy industry. The results are most pronounced with regard to the methane-mitigating part. The 3-NOP supplement led to a methane reduction with 3-NOP of 20-25% in a typical Flemish ration. The replacement of soybean meal in a maize-rich ration by the combination of brewers grains and rapeseed meal led to a methane reduction of almost 15% and a reduction of the carbon footprint of 30%. The research project spread the results intensively: via the SMART project website milking, articles in the agricultural press, demo days and seminars for representatives of the feed and dairy sectors. The acquired knowledge are incorporated into the Covenant for Cattle Enteric Emissions, resulting from the Flemish climate policy plan 2021-2030, that was signed on March 29th 2019, by the Flemish Minister of Agriculture and sector organizations.