A method and system for managing a group of dairy animals in which a subgroup of dairy animals to be separated from the group of dairy animals is determined. A planned collection time is determined, at which time it is planned that the dairy animals in the subgroup of dairy animals to be separated are separated from the group of dairy animals. An individual separation period, which is determined by the length of time from a start time, preceding the planned collection time, to the planned collection time, is selected separately, for each individual dairy animal in the subgroup of dairy animals to be separated, in dependence of a property of said individual dairy animal. Each individual dairy animal in the subgroup of dairy animals to be separated is separated from the group of dairy animals during the individual separation period selected for said dairy animal.