Culture Conditions of Aspergillus oryzae in Dried Food-Waste and the Effects of Feeding the AO Ferments on Nutrients Availability in Chickens

摘要

Two experiments were carried out to assess the appropriate incubation conditions namely; duration, moisture content and the ideal microbial inoculant for fermented dried food waste(FW) offered to broilers. The nutrient utilization of birds fed the FWdiets at varying dietary inclusion rates was also compared with a control diet. In Experiment I, different moisture contents(MC) of 30, 40, 50 and 60%, respectively were predetermined to establish the ideal duration of incubation and the microbial inoculant. A 1 mL Aspergillus orxzoe(AO)(1.33 x 10~5 CFU/mL) was used as the seed inoculant in FW. This results indicated that the ideal MC for incubation was 40-50 % while the normal incubation time was > 72 hours. Consequently, AO seeds at 0.25, 0.50, 0.75 and 1.00 mL were inoculated in FW to determine its effect on AO count. The comparative AO count of FW incubated for 72 and 96 hours, respectively showed no significant differences among varying inoculant dosage rates. The FW inoculated with lower AO seedsat 0.10, 0.05 and 0.01 mL were likewise incubated for 72 and 96 hours, respectively and no changes in AO count was detected(p<0.05). The above findings indicated that the incubation requirements for FW should be 40-50% for 72 hours with an AO seed inoculant dosage rate of 0.10 mL. Consequently, in Experiment n, after determining the appropriate processing condition for the FW, 20 five-week old male Hubbard strain were used in a digestibility experiment. The birds were divided into 4 groups with 5 pens(1 bird per pen). The dietary treatments were; Treatment 1 : Control(Basal diet), Treatment 2 : 60% Basal+40% FW, Treatment 3 : 60% Basal+20% FW+20% AFW(Aspergillus oryzae inoculate dried food-waste diet) and Treatment 4 : 60% Basal+40% AFW. Digestibilityof treatment 2 was lowed on common nutrients and amino acids compared with control(p<0.05) and on crude fat and phosphorus compared with AFW treatments(T3, T4)(p<0.05). Digestibility of treatment 3 and 4 increased on crude fiber and crude ash compared treatment 2 (p<0.05). Digestibility of control was high on arginine, leucine, and phenylalnine of essential amino acids compared with treatment 3 and 4(p<0.05), and diestibility of treatment 3 and 4 was improved on arginine, lysine, and threonine of essential amino acids. Finally, despite comparable nutrient utilization among treatments, birds fed the dietary treatment containing AO tended to superior nutrient digestion to those fed the 60% Basal+40% FW.