PROBLEM TO BE SOLVED: To obtain a constitution capable of accurately determining a growth stage of a living object .SOLUTION: A growth stage model DB113 stores a growth stage model which defines a boundary condition for determining a boundary between growth stages in a plurality of growth stages of a living object by using growth indicator being an indicator of a growth level of the living object for each boundary. An information acquisition part 111 acquires a growth indicator observed value being a value of the growth indicator which is observed in the living object. A growth stage determination part 114 collates the growth indicator observed value acquired by the information acquisition part 110 with each boundary condition defined in the growth stage model, and determines a current growth stage of the living object.SELECTED DRAWING: Figure 2
