Table 3.
Effects of dietary different tryptophan levels on the reproductive performance of duck breeders in the laying period (33 to 34 wk).
| Trp level (g/kg)1 |
P value |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Variables | 1.0 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 | SEM | ANOVA | Linear | Quadratic |
| Average egg weight (g) | 61.1 | 61.5 | 62.1 | 61.1 | 60.9 | 61.0 | 0.25 | 0.757 | 0.447 | 0.527 |
| Fertility of set eggs (%) | 86.5 | 82.4 | 77.9 | 76.3 | 81.3 | 76.9 | 1.48 | 0.327 | 0.081 | 0.119 |
| Hatchability of fertile eggs (%) | 49.8 | 67.2 | 76.6 | 65.7 | 70.4 | 70.8 | 2.97 | 0.058 | 0.088 | 0.065 |
| Healthy duckling (%) | 95.7 | 95.6 | 97.7 | 93.4 | 97.4 | 96.7 | 0.87 | 0.768 | 0.736 | 0.917 |
| 1-d hatchling body weight (g)2 | 39.4 | 39.7 | 40.5 | 40.0 | 39.0 | 38.7 | 0.27 | 0.448 | 0.276 | 0.133 |
1
Mean of 6 replicates (50 eggs per replicate) per treatment.