Mechanism and outcome of aerobic composting of poultry excreta using sawdust during summers

Abstract

To understand the mechanism of aerobic composting of poultry excreta due to C: N ratio, under Indian conditions, meshed iron wire made bins (1.2 × 1.2 × 1.2 cum) were used. The initial C: N ratio was adjusted by using saw dust at 15: 1 (T1); 20: 1 (T2); 25: 1 (T3) and 30: 1 (T4). The moisture content was 45–50%. Crude poultry excreta without sawdust acted as control (T0) whose initial C: N ratio was 10: 1. Parameters recorded were bin temperature, pH, electrical conductivity (EC), proximate composition, C: N ratio, calcium, phosphorus, potassium, microbial profile, germination potential, input-output costs, etc. Thermophilic phase and bin temperature were significantly higher (P<0.01) in all treated groups than control. pH and EC were significantly higher (P<0.01) in T0 than treated groups. Significantly (P<0.01) lower ash and higher organic matter were estimated in T2, T3 and T4 groups than T0 and T1. C: N ratio, N and P content was significantly higher in T3 and T4 than the remaining groups. E. coli was not detected in the finished compost of all treated groups. Gram seed germination (%) was better in treated groups than control. Value addition was in order of T1, T3, T2 and T4. It was concluded that composting poultry excreta with 1: 25 to 1: 30 C: N ratio resulted in better manure production and bio-safety along with higher income generation from invaluable excreta.