Are increasing nutritional requirements of dairy cows consistent with sustainability?

Until now, the milk yield of dairy cows has steadily been increasing. Consequently, their nutritional requirements are also increasing. This requires a higher proportion of concentrates in their ration. It is a trend which leads to intensive production systems with high needs for energy and nitrogen. This may not be brought in line with an objective of sustainable development. Although most often bred in intensive systems, high producing dairy cows are well able to adapt to sustainable systems which are based on a substantial utilisation of forage. Because of their large rumen, dairy cows have a high intake capacity for forage. A marked ability to mobilise body reserves at the onset of lactation enables them to cover the part of their requirements not met by the ration. There are limits to this capacity to mobilise reserves which define the cow’s potential of milk production. Under best conditions in Switzerland, this potential for multiparous cows lies between 8’000 and 10’000 kg per lactation, with peak daily production between 40 and 50 kg. As high producing