Table 7. Growth performance and processing yields of broilers fed gradient levels of dig. Lys from 28 to 42 d of age1 (Experiment 3).
| Item | BW gain, g | FCR2, g/g | Feed intake, g | Lys intake, g/d | Carcass yield3, % | Breast meat yield4, % |
|---|---|---|---|---|---|---|
| Digestible Lys, % | ||||||
| 0.68% | 1,457 | 2.039 | 2,970 | 1.44 | 78.60 | 21.66 |
| 0.76% | 1,594 | 1.899 | 3,029 | 1.64 | 78.89 | 23.01 |
| 0.84% | 1,709 | 1.809 | 3,090 | 1.85 | 80.07 | 24.44 |
| 0.92% | 1,769 | 1.716 | 3,036 | 1.99 | 80.64 | 25.65 |
| 1.00% | 1,769 | 1.721 | 3,042 | 2.17 | 80.34 | 25.17 |
| 1.08% | 1,782 | 1.700 | 3,030 | 2.34 | 79.82 | 25.15 |
| SEM | 18.54 | 0.018 | 11.91 | 0.05 | 0.16 | 0.23 |
| P-value | ||||||
| Linear response | 0.0001 | 0.0001 | 0.0250 | 0.0001 | 0.0006 | 0.0001 |
| Quadratic response | 0.0001 | 0.0001 | 0.0298 | 0.0706 | 0.0013 | 0.0001 |
1 Values are least square means of 8 replicates with 25 birds each for 0.68% digestible Lys and 16 replicates with 25 birds each for all other treatments.
2 Feed conversion ratio corrected for mortality weight.
3 Means from 8 replicates of 6 birds each (n = 288); carcass yield as a percentage of live weight.
4 Breast meat yield expressed as a percentage of carcass weight.