Abstract
As livestock production in Japan becomes more intensive, livestock wastes cause serious environmental problems. In this study, a computer program for estimating the amount of livestock wastes was developed to obtain fundamental data for solving these problems. This program is based on Japanese feeding standard for livestock. The number of livestock, body weight, daily gain, milk yield, the amount of feed intake, the contents of total digestible nutrients, digestible crude protein, crude protein and total phosphorus were necessary for calculations. A simulation of this program shows that the increase of milk yield causes the decrease of the amount of nitrogen and phosphorus in wastes of milking cow per 1kg milk (g/kg-milk). This result supplies a suggestion for deciding appropriate milk yield. Daily amounts of livestock wastes (flesh and dry matter weight, nitrogen and phosphorus) under normal feeding conditions were calculated by this program. These values were useful for estimating loadings of animal wastes onto cropland.
