Abstract: The invention relates to a method for determining at least one state variable of the organism of at least one farm animal, wherein at least one probe device for measurement of at least one physical parameter is disposed in the gastro-intestinal tract of the farm animal and at least one evaluation unit is disposed outside the gastro-intestinal tract of the farm animal, characterized by the following steps: determining at least one first physical parameter by the probe device; converting the first physical parameter into a first state variable of the organism of the farm animal in a probe control unit of the probe device; transmitting the first state variable by the probe device to the evaluation unit; andconverting the first state variable into a second state variable in the evaluation unit. The invention further relates to a probe device for measuring at least one state variable of the organism of a farm animal as well as a system comprising at least one such probe device and an evaluation unit.

Abstract: The invention relates to a measuring device for the measurement of at least one physiological parameter of a farm animal's organism, whereby the measuring device is placeable in the gastro-intestinal tract of livestock and comprises the following components arranged in a casing: at least one sensor for the measurement of at least one physiological parameter of a farm animal, at least one transmitter with antenna for the wireless transmission of information, at least one control unit for controlling the measuring device, and at least one power supply device for the measuring device, whereby a hollow protective guard is provided inside the casing which covers at least the power supply unit in order to protect it from mechanical impact.

Abstract: The invention relates to a measuring device for the measurement of at least one physiological parameter of a farm animal's organism, whereby the measuring device is placeable in the gastro-intestinal tract of livestock and comprises the following components arranged in a casing: at least one sensor for the measurement of at least one physiological parameter of a farm animal, at least one transmitter with antenna for the wireless transmission of information, at least one control unit for controlling the measuring device, and at least one power supply device for the measuring device, whereby a hollow protective guard is provided inside the casing which covers at least the power supply unit in order to protect it from mechanical impact.