[Quantitative determination of chewing and rumination activities in dairy cows].

A device is described (RMBZ) which allows to register the movements of the lower jaws of cattle during food consumption and rumination. A microfeeler is connected to the device which is fastened to the halter. With the use of this device following data can be obtained separately: the total number of chewing movements; the number of bits of food swallowed and the length of chewing period in this way it has become possible to avoid the laborious and time-consuming work that is necessary to analyze strip charts. Trials were performed with varying patterns of food ration showing that this device is particularly suited for studies of this kind especially when compared with other devices using strip charts. Average deviations, e.g. in the number of rumination activities, from those registered with the recorder device were +/- 5%. The measuring technique and the operating principle of the RMBZ device are described in some detail.