Leaf protein production and use on the farm: an economic study

A linear programming model to provide information on the economic feasibility of on-farm production and use of leaf protein from grass is described. The unwilted grass is mechanically separated into a protein-rich ctird, which is fed to pigs or other non-ruminants, and a high-dry matter, fibrous residue which is ensiled and fed to ruminants. In the model, the gross margin from a livestock farm which uses a conventional silage system for a dairy herd is compared with that from the same farm using forage fractionation. The difference in gross margins is available to pay for the additional cost of the fractionation equipment and to provide additional profit. The model considers the machinery performance, costs and labour constraints within which the new system would have to operate if it were to be economic. Results indicate that under a wide range of farm sizes and situations, forage fractionation shows an economic advantage over present forage conservation methods if machinery of the required throughput and cost were to be developed for on-farm use.