An important problem in farm management is to feed animals in an optimal manner to achieve maximum food production subject to constraints. In this paper, we use optimal control to develop optimal feeding policies for sheep, swine, and shrimp. We derive optimal control policies by three different methods: 1) continuous optimal control, 2) hybrid continuous optimal control with discretized feeding policy, and 3) discrete optimal control with discretized feeding policy. For sheep, the aim is to optimally feed pregnant sheep from gestation to birth of lamb to achieve a desired weight of lamb at the time of birth of the lamb. For swine and shrimp the aim is to achieve a desired weight at the time of sale. Data for animal growth from the Thai government and Thai Agricultural Research Stations was used to develop the models. Numerical solutions from the three optimal control methods were obtained and compared.
