An experiment was conducted to study the effect of two levels of Protease enzyme (100g and 200g /MT) on protein utilization and early reproductive performances of Japanese Quail (Coturnix Coturnix Japonica) chicks until 9 weeks of age. Two hundred and twenty five, day-old Japanese Quail chicks were divided into three identical groups having five replicates of 15 birds in each replicate and allotted randomly into three dietary treatments viz., T1, T2 and T3. The treatments consisted of a standard Quail chick ration as control (T1) and standard Quail chick ration with protease enzyme @100g/MT (T2) and 200g/MT of feed (T3). Chicks in each replicate were housed randomly in individual but identical pens and reared under cage system of management. Standard managemental procedures were adopted throughout the experimental period of nine weeks. Feed and water were provided ad libitum. Birds were fed with Quail chick ration up to six weeks of age and then switched over to Quail layer feed. Day on first egg, average age at sexual maturity (age at 5% production) and percent Hen day egg production (HEDP) were recorded. Bird in T3 group laid first egg on 40th day followed by T2 on 41st day and control on 43rd day and also the results showed that average age at sexual maturity (age at 5 % egg production) was significantly lowest (P<0.05) in T3 (40.80±0.37 days) followed by T2 (42.40±0.51 days) and control T1 (43.80±1.11 days) indicating that microbial protease improve early sexual maturity, through improved protein and amino acid utilization. There is an increasing trend in Hen Day Egg Production (HEDP) in protease supplemented groups viz. T2 (34.83 %) and T3 (32.14 %) up to 9 weeks of age, indicating that microbial protease improve early egg production, through improved protein and amino acid utilization.
