Table 4.
Effect of zinc supplementation, with and without phytase addition, on the percentage weights of the dressed carcass, carcass parts, inner organs, and abdominal fat in White Pekin ducks *.
| Dressing (%) | Front Part (%) | Hind Part (%) | Pancreas (%) | Spleen (%) | Liver (%) | Gizzard (%) | Heart (%) | Abdominal Fat (%) | |
|---|---|---|---|---|---|---|---|---|---|
| Zn addition | |||||||||
| 0 ppm | 65.4 | 41.4 | 24 | 0.333 | 0.061 | 2.25 | 3.79 a | 0.66 | 0.618 |
| 30 ppm | 65.5 | 41.7 | 23.8 | 0.388 | 0.050 | 2.17 | 3.05 b | 0.616 | 0.641 |
| Phytase concentration | |||||||||
| 0 U/kg diet | 66.6 | 42.3 | 24.2 | 0.352 | 0.055 | 2.39 a | 3.42 | 0.638 | 0.790 a |
| 500 U/kg diet | 64.4 | 40.7 | 23.7 | 0.369 | 0.056 | 2.03 b | 3.41 | 0.614 | 0.472 b |
| Interaction between Zn and phytase | |||||||||
| 0 ppm Zn + 0 U phytase | 67.5 | 43.1 | 24.4 | 0.373 | 0.058 | 2.31 | 4.02a | 0.693 | 0.820 |
| 0 ppm Zn + 500 U phytase | 63.4 | 39.7 | 23.7 | 0.291 | 0.064 | 2.18 | 3.56 a,b | 0.626 | 0.413 |
| 30 ppm Zn + 0 U phytase | 65.6 | 41.6 | 23.9 | 0.332 | 0.051 | 2.46 | 2.83 c | 0.622 | 0.748 |
| 30 ppm Zn + 500 U phytase | 65.4 | 41.7 | 23.7 | 0.446 | 0.048 | 1.88 | 3.26 b | 0.602 | 0.530 |
| p value | |||||||||
| Zn addition | 0.9343 | 0.1353 | 0.7878 | 0.3446 | 0.075 | 0.5699 | 0.0001 | 0.5213 | 0.6869 |
| Phytase concentration | 0.0941 | 0.0729 | 0.4483 | 0.7761 | 0.8531 | 0.0123 | 0.9465 | 0.2596 | 0.0001 |
| Interaction | 0.1293 | 0.0602 | 0.7413 | 0.1188 | 0.4321 | 0.093 | 0.0288 | 0.5684 | 0.9421 |
| RMSE | 2.712 | 1.881 | 1.548 | 0.132 | 0.013 | 0.28 | 0.413 | 0.255 | 0.119 |
* n = 20 samples as five sample per each treatment; RMSE, Root mean square error. a–d means with different superscripts in the same column in similar treatment groups are significantly different; NS, not significant.