Current Concepts of Feed Formulation for Livestock using Mathematical Modeling

Feed cost is the single most factor which determine the profitability of animal farming. In an attempt to economizing the ration formulation several mathematical models have been used with varying success. Among all the methods linear programming (LP) is used effectively for least cost ration or economic concentrate mixture formulation for many years. Least cost ration formulation is criticized because it can not include nutrient variability and cost variability of feed ingredients in the model. The stochastic programming (SP) has been evolved to consider the nutrient variability of the feed stuff in the model for ration formulation. The SP is found more flexible, accurate, and precise in meeting the requested probability levels as compared to linear programming. Several other non-linear optimization programs are used subsequently to tackle the LP problems of feed formulation but could not replace LP as such. The current trend is to combine the advantage of LP and other optimization program to arrive at a possible and acceptable solution. The LP when combined with the advantage of other optimization programs would give a better solution than any other program used singly. The scope of LP, SP, GA (genetic algorithm) and GP (Goal programming) models are discussed and the advantages of combining LP and weighted (GP) is shown with a practical example which has greater prospects of field application.