Table 2.
Implant treatments | NoIMP | IS/200 | SEM | P-values | ||||||
---|---|---|---|---|---|---|---|---|---|---|
Zinc treatments | ZnB | ZnG | ZnS | ZnB | ZnG | ZnS | IMP | Zn | IMP × Zn | |
Steer (n)c | 12 | 11 | 12 | 12 | 12 | 12 | ||||
Body weight, kg | ||||||||||
d 0 | 411 | 411 | 409 | 410 | 412 | 412 | 3.1 | 0.70 | 0.96 | 0.80 |
d 28 | 462 | 461 | 452 | 459 | 469 | 465 | 4.0 | 0.08 | 0.22 | 0.11 |
d 57 | 508 | 506 | 497 | 511 | 520 | 522 | 5.1 | <0.001 | 0.74 | 0.11 |
d 84 | 542yz | 538yz | 536z | 555xy | 567wx | 575w | 6.3 | <0.001 | 0.48 | 0.10 |
d 112 | 586z | 579z | 581z | 611y | 622xy | 637x | 7.3 | <0.001 | 0.30 | 0.10 |
d 126 | 603z | 594z | 591z | 630y | 639xy | 654x | 7.8 | <0.001 | 0.62 | 0.07 |
Average daily gain, kg | ||||||||||
d 0–56 | 1.70yz | 1.65yz | 1.55z | 1.77xy | 1.90x | 1.91x | 0.069 | <0.001 | 0.75 | 0.08 |
d 57–126 | 1.38 | 1.28 | 1.37 | 1.72 | 1.72 | 1.91 | 0.070 | <0.001 | 0.12 | 0.32 |
Dry matter intake, kg | ||||||||||
d 0–56 | 10.5 | 10.6 | 9.8 | 10.5 | 10.8 | 10.4 | 0.28 | 0.23 | 0.08 | 0.55 |
d 57–126 | 10.4 | 10.5 | 10.3 | 10.9 | 11.0 | 11.5 | 0.36 | 0.01 | 0.84 | 0.45 |
Zn intake, mg/d | ||||||||||
d 0–56 | 1367 | 1295 | 1310 | 1367 | 1321 | 1398 | 37.2 | 0.20 | 0.24 | 0.45 |
d 57–126 | 1361 | 1294 | 1383 | 1419 | 1353 | 1549 | 46.9 | 0.01 | 0.01 | 0.40 |
G:Fd | ||||||||||
d 0–56 | 0.161 | 0.147 | 0.174 | 0.200 | 0.194 | 0.228 | 0.0093 | <0.001 | 0.01 | 0.70 |
d 57–126 | 0.132 | 0.121 | 0.133 | 0.160 | 0.156 | 0.169 | 0.0072 | <0.001 | 0.19 | 0.83 |
Overall performance | ||||||||||
ADGe, kg | 1.49z | 1.41z | 1.38z | 1.69y | 1.74xy | 1.84x | 0.060 | <0.0001 | 0.53 | 0.07 |
DMI, kg | 10.5 | 10.6 | 10.1 | 10.7 | 10.9 | 11.0 | 0.30 | 0.03 | 0.74 | 0.45 |
G:F | 0.15 | 0.14 | 0.15 | 0.16 | 0.17 | 0.18 | 0.005 | <0.0001 | 0.13 | 0.36 |
Carcass-adjusted performancef | ||||||||||
Final BW, kg | 598 | 590 | 590 | 635 | 637 | 660 | 8.7 | <0.0001 | 0.33 | 0.12 |
ADG, kg | 1.48 | 1.42 | 1.44 | 1.79 | 1.79 | 1.98 | 0.062 | <0.0001 | 0.21 | 0.12 |
G:F | 0.14 | 0.13 | 0.14 | 0.17 | 0.16 | 0.18 | 0.005 | <0.0001 | 0.02 | 0.49 |
a Implant strategies included no implant (NoIMP) or a Component TE-IS (IS/200; 80 mg trenbolone acetate + 16 mg estradiol; Elanco Animal Health, Greenfield, IN) on day 0 followed by a Component TE-200 (200 mg trenbolone acetate + 20 mg estradiol; Elanco Animal Health) on day 57.
b Cattle received 70 mg Zn/kg DM from ZnSO4 + 30 mg Zn/kg DM from basic ZnCl, Zn glycinate, or ZnSO4 (ZnB, ZnG, or ZnS, respectively). Total Zn supplementation was targeted at 100 mg Zn/kg DM to meet industry consultant recommendations (Samuelson et al., 2016).
c Unlike superscripts represent tendencies for differences between treatment means (0.05 < P ≤ 0.10).
d Feed efficiency.
e Average daily gain was analyzed as repeated measures with the repeated effect of Day. Zn × Day P = 0.01; IMP × Day P = 0.02; Day P < 0.0001; Zn × IMP × Day P = 0.86.
f Carcass-adjusted performance was calculated using the average dressing percent: 64.35%.