An apparatus and method for automatically supplying feed to animals such as cows. A control device generates a control signal for controlling the supply of feed to be consumed by an animal at a feed trough. A parameter-measuring component determines the value of a variable parameter which bears a relationship to the feed to be supplied to an animal at the feed trough and issues a parameter value signal to the control device. The control device is provided with a processing device for processing the parameter value signal into the control signal. The parameter-measuring component measures the parameter involved which relates to an animal that feeds at the feed trough and issues a signal providing information as to that parameter to the processing device. The parameters which may be measured include the existing physical condition profile of the animal, the rate that the animal consumes feed from the feeding trough, the existing milk yield of an animal at the feeding trough, and the amount of one or more ingredients which are present in the milk produced by the animal at the feeding trough, including proteins, fat, minerals and amino acids.