EXPERIMENT ON LAYER FEEDS COMPRISING OF PROTEIN-RICH RICE CULTIVATED BY TREATED MUNICIPAL WASTEWATER

Abstract

 Our previous studies revealed the successful cultivation of protein-rich rice for feed by effective reuse of treated municipal wastewater (TWW). This study evaluated the possibility to substitute such protein-rich rice for corn in conventional diets of laying hens. Production and quality of eggs were compared between the layers feeding on a conventional diet (control), which composed of corn and soybean cake as energy and protein sources, respectively, and those fed by the protein-rich rice and soybean cake (test feed). Results showed that, owing to higher protein content in the rice relative to that in corn, the test feed reduced the usage of soybean cake by 30% compared with the control, although eight times larger amount of wheat bran, as an auxiliary material, was required to keep the nutrient balance of feed. Since soybean cake is generally highly priced compared to corn, its reduced usage could likely result in more profit for farmers even if the increased cost for wheat bran is considered. In addition, egg production and its quality observed under the test feed are comparable with those recorded under the control diet, implying that the protein-rich rice is a highly feasible substitute for corn to reduce the feed cost without compromising the egg production and quality. Flavor and taste of the eggs obtained in this experiment were also examined using a sensory test involving skilled panels. Although the boiled eggs under the test feed had milder flavor relative to those under the control, all the boiled eggs had similar taste and texture regardless of the feed types.