Economics of phosphorus fertiliser use on pastures 3. Incorporating animal response

Abstract As a further step in integrating soil — plant — animal relationships for generating management information, a response function of butterfat production to levels of feeding, liveweight, and butterfat production potential was derived. The model was based on current nutritional standards and statistical relationships. Instead of assuming a constant feed conversion coefficient when determining optimal fertiliser levels, the model allowed a more realistic representation of animal response.