MVSc

An experiment was carried out to study the effect of dietary supplementation of lysine and methionine on production performance of Japanese quail layers. Two hundred and fifty six Japanese quails at 6 weeks of age were allocated randomly to four dietary groups with four replicates of sixteen quails each. Quail layer ration containing 22 per cent crude protein, 2650 kcal ME per kg feed with 1.0 per cent lysine and 0.45 per cent methionine formed the basal diet T1. The other three diets were formulated by supplementing the basal diet with 0.25 per cent L-lysine (T2), 0.25 per cent DL-methionine (T3) and a combination of both at 0.25 per cent level (T4). The experiment was carried out for five periods of 28 days each from 7 to 26 weeks of age.
The mean body weight of the quails in all the dietary groups was comparable at the beginning of the experiment, but at 26 weeks of age the group T3 (215.04 g) had significantly lower mean body weight than that of T1 and T2 (225.83 and 225.60 g). Even though the age at first egg in the flock in each dietary group was 42 days, the group T3 attained 50 per cent production early (49 days) and T2 late (54 days). The overall mean quail housed and quail day number and per cent production were statistically comparable among the dietary groups. The mean EW in the group T1 (11.17 g) was significantly (P≤0.05) lower than that of amino acid supplemented groups. The cumulative mean egg mass per quail on quail day basis did not differ significantly between groups. The overall daily feed consumption per quail was numerically higher in T2 (31.53 g). Feed conversion ratio per dozen eggs as well as per kg egg mass did not show any significant difference among dietary groups. Statistical analysis of the overall mean values of egg quality traits revealed no significant difference between dietary groups. The per cent dressed yield excluding skin was significantly higher in T3 (86.63) compared to T2 and T4 while per cent of skin and feather put together showed the opposite trend. The per cent losses of blood and ovary and oviduct were comparable among the dietary groups. The per cent yield of eviscerated carcass and ready-to-cook yield excluding skin, liver and giblet did not show significant difference between the dietary groups. The mean value of serum protein was comparable in all groups. Serum total cholesterol was significantly higher in T4 (248.62 mg/dl) compared to T1 and T2 and was comparable to that of T3. The overall livability per cent did not differ significantly among dietary groups. The cost of feed per egg was significantly lower in T1 (35.21 paise) compared to T4 (39.92 paise) and was intermediate in T3 (37.06 paise) and T2 (38.91 paise).
The critical evaluation of the results revealed that the supplementation of 0.25 per cent L-lysine, 0.25 per cent DL-methionine or its combination significantly improved mean egg weight in cage reared quails. The quail layer ration containing 22 per cent crude protein with 1.0 per cent lysine and 0.45 per cent methionine was the most economical without supplementation of crystalline amino acids. The supplementation of the ration with 0.25 per cent DL-methionine was the next cost-effective, followed by the ration with 0.25 per cent L-lysine supplementation. The combined supplementation of L-lysine and DL-methionine was economically not feasible in quail layer diets.