Table 2.
Influence of GH inclusion in replacement of corn silage on animal growth performance and dietary energetics of newly weaned beef steers during the feedlot receiving phase
| GH Inclusion, % (DM basis) | P-value | |||||
|---|---|---|---|---|---|---|
| Item | 0 | 10 | 20 | SEM | Linear | Quadratic |
| Days | 56 | 56 | 56 | — | — | — |
| Pen, n | 6 | 6 | 6 | — | — | — |
| Steers, n | 54 | 54 | 54 | — | — | — |
| Growth performancea | ||||||
| Initial BW, kg | 278 | 278 | 277 | 0.3 | 0.12 | 0.30 |
| Final BW, kg | 352 | 353 | 357 | 2.7 | 0.21 | 0.62 |
| ADG, kg | 1.33 | 1.35 | 1.43 | 0.048 | 0.16 | 0.54 |
| DMI, kg/d | 6.46 | 6.74 | 7.04 | 0.105 | 0.01 | 0.93 |
| Gain:feed | 0.206 | 0.200 | 0.204 | 0.0045 | 0.72 | 0.37 |
| Expected DMI, kg | 7.60 | 7.92 | 8.51 | 0.208 | 0.01 | 0.62 |
| Expected ADG, kg | 1.00 | 1.03 | 1.05 | 0.023 | 0.21 | 0.91 |
| pa NE, Mcal/kgb | ||||||
| Maintenance | 2.05 | 1.99 | 1.99 | 0.022 | 0.10 | 0.30 |
| Gain | 1.39 | 1.33 | 1.34 | 0.020 | 0.10 | 0.30 |
| Observed/expected | ||||||
| NEM | 1.16 | 1.14 | 1.17 | 0.013 | 0.45 | 0.23 |
| NEG | 1.19 | 1.20 | 1.24 | 0.017 | 0.11 | 0.60 |
| DMI | 0.85 | 0.85 | 0.83 | 0.011 | 0.19 | 0.42 |
| ADG | 1.32 | 1.31 | 1.37 | 0.026 | 0.26 | 0.35 |
aInitial BW was the average of day −1 and day 1 BW, and final BW was from day 56 and was pencil shrunk 4% to account for gastrointestinal tract fill.
bpaNE calculated from observed steer growth performance (Zinn and Shen, 1998; Zinn et al., 2008).