This disease is also known by the names parturient paresis, paresis of parturition, parturient fever, milk fever. The word “fever” in connection with the terminology of this disease is not very appropriate, because in the majority of cases fever is not present, but the animal has a subnormal temperature. The term milk fever is very misleading and indefinite, as it is also used by the laity to designate other diseases, such as parturient septicaemia and the various forms of mammitis. Parturient paralysis must be clearly differentiated from parturient septicaemia, which is a disease of an entirely different character and which may occur in any of the domestic species, whereas parturient paralysis occurs only in the cow.