Prototyping of Organic Dairy Production Systems Self-sufficient with Feed—Consequences on Productivity, Economy and Nutrient Balance

In 2005, it became obligatory to feed all organic dairy cows in the EU 100% organically. To create a better understanding of the possible effects this would have on the whole farming system, six production strategies were formulated and the effects on productivity, economy and nutrient balance were analysed. The strategies differed with respect to type of concentrated feed, level of fresh grass-clover in the ration and length of the calving interval. It was found that supplementation with cereals, rapeseeds/cereals or grass pellets as well as increased level of grazing gave very similar productivities and financial results, but supplementation with rapeseed cakes reduced crop production and the financial result. On the assumption of a positive effect on milk yield persistency and feed intake per cow, prolonged calving interval had a positive effect on the productivity and the financial result of the organic dairy farm. Due to lower inputs a self-sufficient system offers opportunities for reducing N surpluses, but also indicates the risk of P and K deficits and the need for additional fertilizer inputs.