Finding graze time - combining grazing with automatic milking

The introduction of automatic milking systems (AMS) within European dairy farming in the past decades has been accompanied by a decline in grazing and in time spent outdoors by dairy cows. Grazing is a natural behaviour of cattle, and the opportunity to go outdoors is often considered a component of animal welfare. Grazing ruminants can also utilise land unsuitable for human food production, while supplying ecosystem services such as maintaining biodiversity and increasing carbon sequestration. Thus many stakeholders in society want farmers to retain dairy management systems that include grazing. Pasture availability and nutritive quality can fluctuate considerably during the grazing season. This variation, together with lack of accurate methods for cow-side pasture dry matter intake determination as decision support for supplementary feeding, can compromise nutrient supply to high-yielding cows. Therefore farmers often feed high amounts of supplements to maintain milk production level throughout the grazing season. Other constraints, e.g. a need for continuous access between pastures and milking unit, areal requirements for larger herds and high costs of grazing infrastructure, can further reduce farmers’ enthusiasm for grazing and increase their frustration with statutory grazing requirements. This thesis examined constraints frequently ascribed to combining grazing with AMS and tested the validity of these associations under experimental and real-life conditions. The results showed that solutions are possible whereby dairy farmers can offer high-yielding cows pasture in their diet, without compromising farm finances through associated yield losses