Table 4.
Main effects of yeast pre- and probiotics and pharmacological levels of Zn on nursery pig performance1
| Item | Yeast additives | SEM | P-value | Zinc | SEM | P-value | ||
|---|---|---|---|---|---|---|---|---|
| No yeast | Yeast | Low Zn | High Zn | |||||
| BW, kg | ||||||||
| d 0 | 5.64 | 5.64 | 0.024 | 0.779 | 5.64 | 5.64 | 0.024 | 0.901 |
| d 7 | 5.95 | 5.99 | 0.060 | 0.508 | 5.86 | 6.07 | 0.060 | 0.001 |
| d 21 | 11.21 | 11.31 | 0.122 | 0.533 | 10.96 | 11.56 | 0.122 | < 0.001 |
| d 42 | 23.58 | 23.66 | 0.202 | 0.744 | 23.22 | 24.01 | 0.202 | 0.002 |
| Phase 1 (days 0 to 7) | ||||||||
| ADG, g | 44 | 50 | 7.3 | 0.489 | 32 | 62 | 7.3 | 0.001 |
| ADFI, g | 80 | 81 | 5.0 | 0.847 | 74 | 87 | 5.0 | 0.042 |
| G:F, g/kg | 397 | 547 | 73.1 | 0.077 | 297 | 646 | 73.1 | < 0.001 |
| Phase 2 (days 7 to 21) | ||||||||
| ADG, g | 373 | 380 | 5.9 | 0.401 | 361 | 392 | 5.9 | < 0.001 |
| ADFI, g | 464 | 472 | 9.0 | 0.507 | 445 | 492 | 9.0 | < 0.001 |
| G:F, g/kg | 805 | 808 | 8.4 | 0.810 | 814 | 799 | 8.4 | 0.169 |
| Experimental period (days 0 to 21) | ||||||||
| ADG, g | 262 | 270 | 5.6 | 0.288 | 251 | 281 | 5.6 | < 0.001 |
| ADFI, g | 335 | 342 | 7.3 | 0.461 | 321 | 356 | 7.3 | < 0.001 |
| G:F, g/kg | 782 | 792 | 7.2 | 0.247 | 782 | 791 | 7.2 | 0.282 |
| Phase 3 common period (days 21 to 42) | ||||||||
| ADG, g | 589 | 588 | 5.8 | 0.947 | 584 | 593 | 5.8 | 0.264 |
| ADFI, g | 875 | 868 | 8.1 | 0.573 | 870 | 873 | 8.1 | 0.811 |
| G:F, g/kg | 674 | 677 | 3.9 | 0.502 | 672 | 680 | 3.9 | 0.158 |
| Overall (days 0 to 42) | ||||||||
| ADG, g | 424 | 429 | 4.4 | 0.433 | 417 | 437 | 4.4 | 0.001 |
| ADFI, g | 603 | 605 | 7.0 | 0.830 | 594 | 614 | 7.0 | 0.031 |
| G:F, g/kg | 704 | 709 | 3.5 | 0.284 | 702 | 712 | 3.5 | 0.043 |
| Fecal dry matter, %2 | ||||||||
| d 4 | 18.9 | 18.8 | 0.82 | 0.955 | 17.7 | 20.0 | 0.82 | 0.043 |
| d 21 | 22.0 | 22.9 | 0.81 | 0.397 | 22.6 | 22.3 | 0.81 | 0.786 |
| d 42 | 24.5 | 23.6 | 0.85 | 0.437 | 24.0 | 24.2 | 0.85 | 0.891 |
1A total of 360 barrows (initially 5.6 ± 0.03 kg) were used in a 42-d growth study with 5 pigs per pen and 36 pens per treatment. Yeast pre- and probiotics included ActiSaf Sc 47 HR+ at 0.10.%, SafMannan at 0.05% and NucleoSaf at 0.05% in phase 1 diets and then concentrations were lowered by 50% in phase 2 diets (Phileo by Lesaffre, Milwaukee, WI). ZnO was fed to supply 3,000 mg/kg of Zn for the duration of phase 1 and 2,000 mg/kg of Zn for the duration of phase 2. All yeast additive × zinc interaction, P > 0.05.
2Fecal samples from the same 3 pigs/pen were collected on days 4, 21, and 42. Zinc × yeast × day, P = 0.790; Zinc × day, P = 0.220; Yeast × day, P = 0.515.