Odour reducing fermentation agent for animals waste, partic. with added fillers e.g. calcium carbonate, comprises a symbiotic cultured mixt. of Thermoactinomyces SK053 sp. nov (FERM P-13598) having characteristic features of broad growth temp. range of 10-85 deg.C and pH range of 5.3-10.8, lignin solubilising and fibrinolytic properties and Clostridium thermocellum biovar. SK522 (FERM BP-3459) having characteristic features of growth temp. range of 40-80 (65-72)deg.C and active fibrinolytic property, partic. in the presence of the other fibrinolytic microorganism. Thermus aguaticus biovar SK542 (FERM BP-3382) having characteristic features of (1) growth temp. range of 40-82, (pref. 72-78 esp. 75-85) deg.C, (2) pH range of 4.0-11.3, and (3) proteolytic enzyme and carotinoid yellow pigment productivities. Thermophilic actinomycetes Thermoactinomyces SK053 (FERM P-13598), Clostridium thermocellum biovar, SK522 sp. nov. (FERM BP-3459) and Thermus aguaticus biovar SK542 (FERM BP3382), including aerobic fibrinolytic microorganisms having optimum temp. of 22-35 deg.C (e.g. Bacillus fimi and Actinomyces melanocyclus), anaerobic fibrinolytic microorganisms having optimal temp. of 25-37 deg.C (e.g. Clostridium werneri and Plectridium cellulolyticum) and thermophilic fibrinolytic microorganisms having optimum temp. of 55-65 deg.C (e.g. Clostridium thermocellum and Bacillus cellulosae dissolvens) and denitrifying fibrinolytic microorganisms having optimum temp. of 35 deg.C (e.g. Bacterium cellaresolvens) are pref. used for fermentation of faeces.    ADVANTAGE -   Odour reduced prodn. of fertiliser from animal faeces including humans may be effected.    In an example, in a digesting tank, 2kg human waste and 1kg symbiotic culture of Thermoactinomyces SK053 sp. nov and Clostridium thermocellum biovar, SK522 were placed and fermented for 20 days. The concn. of Me2S and 513, 55, 20 and 7 ppb on day 2,5,10 and 20, respectively. A control gp. without addn. of the symbiotic culture showed corresp. concn. of 845, 1,160, 1,210 and 1,093 ppb, respectively.