Effect of sweet, bitter and soaked micronised bitter lupins on broiler performance.

1. The feeding value for broilers of sweet white lupins (Lupinus albus variety Hanti), bitter lupins (Lupinus angustifolius) and soaked micronised bitter lupins was examined. 2. Four isocaloric and isonitrogenous diets were formulated; one contained no lupins and the other 3 contained 400 g/kg sweet, bitter or soaked micronised bitter lupins. The 3 lupin diets were blended appropriately to produce 16 experimental diets containing 0, 50, 100, 200, 300 and 400 g/kg sweet, bitter and soaked micronised bitter lupins, respectively, and these were fed to Ross broilers for 6 weeks. 3. The feeding of diets containing bitter lupins to broilers at 300 and 400 g/kg and soaked micronised bitter lupins at 400 g/kg resulted in significantly different body weights, food intakes, food conversion ratios, carcase moisture and carcase fat contents from those of birds fed on the control diet. No significant differences were observed with carcase protein or carcase ash contents. 4. There were significant linear adverse responses with bitter and soaked micronised bitter lupins in most of the parameters studied whereas no responses were observed with sweet lupins as the dietary inclusion rate of the lupins increased. The soaked micronised bitter lupins performed better than the bitter lupins showing that the amount of bitter lupins in broiler diets can be increased by this method.