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Graded levels of moisture were added to corn-soybean based formulations to create pelleted diets that differed in energy density. The pelleted diets were assessed using feed manufacturing parameters, pellet quality, performance, and energy metabolism of broilers during the growing phase. Treatments consisted of a factorial arrangement of three levels of added moisture (0, 2.5, and 5%) and two levels of energy density [NRC-recommended levels and 5% less than NRC recommended levels (low energy)]. NRC diets demonstrated increased pellet production rate, decreased pellet starch gelatinization, and decreased pellet durability compared to low energy diets during manufacture. Moisture addition, independent of dietary energy density, increased pellet production rate, decreased relative electrical energy usage, decreased pellet starch gelatinization, and increased pellet durability. These results suggest that moisture addition to broiler diets may increase economic returns of pellet manufacturing while simultaneously increasing pellet quality. In subsequent feeding experiments, broilers fed NRC diets in general demonstrated decreased feed intake and increased feed efficiency (FE) compared to broilers fed lower energy diets. However, broilers fed lower energy diets that included moisture additions demonstrated statistically similar FE compared to broilers fed NRC diets without added moisture. Broiler live weight gain and mortality were not affected by any treatment combination. In addition, broiler-derived true metabolizable energy values did not differ among treatments. These findings imply that feeding lower energy formulations that incorporate moisture can produce broiler FE equivalent to broilers fed NRC corn-soybean formulations, presumably due to benefits associated with improved pellet quality, which do not include increased metabolizable energy. |
