How to manage cows yielding 20,000 kg of milk: technical challenges and environmental implications

The world cow milk production will reach between 810 and nearly 1,000 Mt in 2050, implying changes in dairy farm management as well implications in environmental impact, especially as far as greenhouse gases (GHG) emissions, and nitrogen and phosphorus excretions are concerned. The future dairy farms will need to become smarter, profitable, and high yielding to continuously improve the sustainability of milk production. Among western countries, the Italian dairy industry has good performances both for milk yield and quality. Most of its milk is used to produce highly exported PDO cheeses with high added value. It could represent a model to study the impact of accelerated phenotypic trend on technical and environmental challenges. Assuming a constant average increase of milk yield equal to the actual phenotypic trend (+128 kg per cow and per year), the production of the current best cows (20t/head year−1) will become the average herd performance of the intensive dairy farms in 2030. Thus, maintaining the current Italian milk production (equal to 12.1 Mt), the higher milk production per head would cause a reduction of the environmental impact of 11.4% and 60.1% for GHG, 9.1% and 36.0% for N, 15.8% and 52.6% for P considering two scenarios of present phenotypic trend or 20t/head year−1, respectively. To cope with this challenge, technical suggestions for breeding and feeding the 20t dairy cow are given.Highlights Current top Italian cows represent the 2030 average of dairy herds Genomics and management will drive the productivity success Efficiency will reduce dairy environmental impact.n