A system for automatically determining pregnancy toxaemia in at least one animal in a group of animals comprises a sensor for obtaining at least one value representative of a liquid or water uptake of the at least one animal, said sensor being adapted to be positioned in the vicinity of a liquid or water supply station or on the at least one animal; and a processing unit configured for comparing the obtained at least one value representative of a liquid or water uptake of the at least one animal to a mean value representative of an average of the at least one value for the group of animals or to a value deduced therefrom; and for generating a signal and/or alert when the obtained at least one value representative of a liquid or water uptake exceeds the mean value or the value deduced therefrom by a pre-determined threshold value.