The invention relates to a method and a system for estimating the feeding value or the amount of consumed herbage of grazing animals. The estimated herbage uptake is based on measured and possibly estimated data which is supplied as input data to a mathematical model. Measured input data may be acceleration data of the head of the animal, the length of herbage and the quality, i.e. feeding value, of herbage. Estimated input data may be the frequency of the reciprocate head motion of the animal and the in-active or active grazing status of the cow. Alternatively, the estimated data may be determined by the model and possibly provided as output data. Measurements may be obtained by a sensor module carried by the animal and the measurements may be wirelessly transmitted from the sensor module to a receiver, possibly via relay transceivers.
