Table 2.
Effects of beef genotypes and finishing system on performance and carcass traits (mean and lower and upper confidence limit at 95%)
| Item | Genotype1 | System | Year | |||
|---|---|---|---|---|---|---|
| RA | AK | GRASS | GRAIN | 2019 | 2020 | |
| Growth2 | ||||||
| Initial BW, kg | 454.2(445.6 − 462.9) | 459.7(451.1 − 468.4) | 436.5 (428.7 − 444.2) | 477.5 (467.8 − 487.2) | 454.4(446.7 − 462.2) | 459.5(449.9 − 469.2) |
| Final BW, kg | 592.8(581.9 − 603.6) | 590.6(579.8 − 601.5) | 563.5 553.8 − 573.2) | 619.9 (607.7 − 632.1) | 579.9 (570.2 − 589.6) | 603.5 (591.3 − 615.6) |
| Total gain, kg | 134.6(129.6 − 139.6) | 128.5(123.5 − 133.5) | 119.4 (115.0 − 123.9) | 143.7 (138.1 − 149.3) | 120.5 (116.0 − 125.0) | 142.6 (137.0 − 148.2) |
| ADG, kg d−1 | 1.25(1.21 − 1.31) | 1.20(1.15 − 1.25) | 1.19 (1.15 − 1.24) | 1.26 (1.21 − 1.32) | 1.28 (1.24 − 1.32) | 1.18 (1.12 − 1.23) |
| Carcass3 | ||||||
| Wgt at slaughter, kg | 571.6(561.3 − 582.0) | 572.3(561.7 − 582.9) | 547.4 (538.2 − 556.7) | 596.5 (584.6 − 608.4) | 559.7 (550.5 − 569.0) | 584.2 (572.3 − 596.1) |
| HCW, kg | 337.4(331.2 − 343.7) | 345.7(339.4 − 351.9) | 314.9 (309.3 − 320.5) | 368.2 (361.2 − 375.2) | 333.2 (327.6 − 338.8) | 349.9 (342.8 − 356.9) |
| Dressing, % | 59.1 (58.7 − 59.4) | 60.5 (60.1 − 60.9) | 57.6 (57.3 − 57.9) | 61.9 (61.5 − 62.4) | 59.5 (59.1 − 59.8) | 60.1 (59.7 − 60.5) |
| Backfat, mm | 9.7(8.9 − 10.7) | 9.9(9.0 − 10.9) | 5.9 (5.5 − 6.4) | 16.3 (14.7 − 18.1) | 9.6(8.8 − 10.4) | 10.1(9.1 − 11.2) |
| Ribeye area, cm2 | 72.1 (70.2 − 74.0) | 74.9 (73.0 − 76.8) | 69.2 (67.5 − 70.9) | 77.8 (75.7 − 80.0) | 72.3(70.6 − 74.0) | 74.7(72.6 − 76.9) |
| Ribeye, cm2 CW−1 | 9.7 (9.4 − 9.9) | 9.9 (9.6 − 10.1) | 9.9 (9.7 − 10.2) | 9.6 (9.3 − 9.9) | 9.9 (9.6 – 10.1) | 9.7 (9.4–10.0) |
| USDA yield grade | 2.9(2.8 − 3.0) | 2.9(2.7 − 3.0) | 2.4 (2.3 − 2.5) | 3.5 (3.3 − 3.6) | 2.9(2.8 − 3.1) | 2.9(2.7 − 3.0) |
| Marbling Score | 494.5 (474.8 − 514.3) | 529.2 (509.5 − 549.0) | 404.5 (386.9 − 422.1) | 619.2 (597.1 − 641.3) | 519.2(501.5 − 536.8) | 504.6(482.5 − 526.7) |
1RA = Red Angus; AK = Red Angus x Akaushi crossbred
2BW = Body weight; ADG = Average daily gain
3HCW = Hot carcass weight; Marbling scores: Choice− = 400–499, Choice0 = 500–599, Choice+ = 600–699.
Bold values indicate that the main effect was statistically different (P < 0.05). P-values are shown in Supplementary Table S2.