Feeding policies for dairy cows in the "zona da mata" of Minas Gerais. I. Description of a conceptual model

Abstract

A preliminary computer programme has been written for use as a framework in developing a more comprehensive simulation study of feeding factors affecting dairy cow performance in an important dairying area of the Southeast of Brazil. The programme calculates the energy and protein requirements for the major productive processes of the cow and compares them with the nutrients supplied by pasture. Any deficits of energy or protein are converted into supplementary feeding at a level determined by a linear programming submodel. Gross margin over feeding costs is estimated based on milk output, supplementary feeding costs and value of forage areas. Only the modal description is reported here while the results of its application will be shown in future papers.