ABSTRACT

 
Two feeding trials were conducted to evaluate the effect of sweet potato and sweet potato peel meals on the growth and laying performance of Japanese quails (Coturnix coturnix japonica). One thousand Five hundred and six Japanese quails were used for the study. In experiment 1, three hundred mixed sexes of 2 weeks old Japanese quails (mean weight 32.00g) were fed the different diets of sweet potato meal for a period of 28 days for the grower phase and two hundred and twenty eight female 7 weeks old Japanese quail birds ( mean weight 137.00g) were fed for 112 days for the laying phase. The birds were assigned to four dietary treatments each (0, 10, 20, 30%) of sweet potato meal consisting of 75 grower quails per treatment with three replicates of 25 birds at the grower phase and 57 hens per treatment with three replicates of 19 birds at laying phase. Water and feed were supplied ad libitum. During grower phase, higher final body weight (141.47g) of the Japanese quails was achieved in quail birds fed diets containing 10% sweet potato meal, this was followed by the quail birds fed 0% sweet potato meal (141.28g) while the least final body weight (134.80 g) was obtained in the quail birds fed 30% sweet potato diet. The feed conversion ratio showed no significant (P < 0.05) differences across the entire treatment groups for sweet potato meal. Higher carcass weight (101.52g) of the quails was achieved in birds fed diets containing 10% sweet potato meal. Quails fed diets containing 10% sweet potato meal had better apparent digestibility of nutrients compared to birds fed other diets. Feed cost analysis during grower phase revealed that birds fed diets containing 30% sweet potato meal  304.67) had better feed cost than birds on other diets. The result on laying performance and egg characteristics showed significant (P < 0.05) differences in birds fed sweet potato meal. Hen-day egg production of quails fed 10% sweet potato meal diets (55.71) was significantly (P < 0.05) higher than those of birds fed the other diets. Peak egg production values of birds fed 10% sweet potato meal (83.33 days) was statistically the same with birds fed 0% sweet potato diets (82.31days). There was no mortality recorded during the grower and laying phase. In experiment 2, three hundred mixed sexes of 2 weeks old Japanese quails (mean weight 32.00g) were fed the different diets of sweet potato peels meal for a period of 28 days for the grower phase and two hundred and twenty eight female 7weeks old Japanese quail birds ( mean weight 137.00g) were fed for 112 days for the laying phase. The birds were assigned to four dietary treatments each (0, 10, 20, 30%) of sweet potato peel meal consisting of 75 grower quails per treatment with three replicates of 25 birds at the grower phase and 57 hens per treatment with three replicates of 19 birds at laying phase. Water and feed were supplied ad libitum. At grower phase, higher final body weight (141.33g) of the Japanese quails was achieved in quail birds fed diets containing 10% sweet potato peel meal, this was followed by the quail birds fed 0% sweet potato peels meal (141.28g) while the least final body weight (132.32 g) was obtained in the quails fed diets containing 30% sweet potato peel meal. Quail birds fed 10% sweet potato peel meal performed significantly (P < 0.05) better in feed conversion ratio. Quails on 0% sweet potato peel meal (control) had higher carcass weight (98.80) compared to other dietary treatment (P < 0.05). Birds on 10% sweet potato peel meal performed better than birds on other diets on apparent crude protein digestibility. Feed cost analysis during grower phase revealed that birds fed 30% sweet potato peel meal had better feed cost    247.08) than birds fed other diets. The result on laying performance and egg characteristics showed significant (P < 0.05) differences in birds fed sweet potato peel meal. Hen-day egg production of quails fed 10% sweet potato peel meal diets (52.43) was significantly (P < 0.05) higher than those of birds on the other diets. Peak egg production values of birds fed 10% sweet potato peel meal (82.31days) was statistically similar with birds fed 0% sweet potato diets (82.31). There was no mortality recorded during the grower and laying phase. Inclusion of sweet potato and sweet potato peel meals in the diets of Japanese quails did not result in any detrimental effect on overall performance. Thus substituting maize with sweet potato meal at 10% inclusion and sweet potato peel meal at 10% inclusion in Japanese quails diet resulted in enhanced growth and egg production performance at the least cost. At the growing phase, diets containing sweet potato meal at 10, 20 and 30% levels of inclusion reduced cost of production by  0.62), 3.21%  1.01)   and   5.35%    ( 1.68) respectively while diets containing 10 and 30% sweet potato peel meal reduced the cost of production by 59.04% ( 18.55) and 66.58% ( 66.58) respectively.