Table 5.
Liver abscesses and carcass traits of beef feedlot steers fed finishing diets with increasing proportions of barley silage (n = 5 pens/treatment)
| Barley silage, % of dietary DM | P-value2 | |||||||
|---|---|---|---|---|---|---|---|---|
| Item1 | 0 | 4 | 8 | 12 | SEM | Diet | Linear | Quadratic |
| Liver abscesses,2,3 % of cattle (number of cattle) | ||||||||
| None and mild (0 and 1) | 58.3 (14) | 53.6 (12) | 62.5 (15) | 55.0 (12) | – | 0.92 | – | – |
| Moderate (2 and 3) | 41.7 (10) | 42.3 (10) | 33.3 (8) | 45.0 (9) | – | 0.96 | – | – |
| Severe (3+) | 0 (0) |
4.2 (1) | 4.2 (1) | 0 (0) |
– | 1.00 | – | – |
| Total (2, 3, and 3+) | 41.7 (10) | 46.4 (11) | 37.5 (9) | 45.0 (9) | – | 0.96 | – | – |
| Carcass traits | ||||||||
| Hot carcass weight, kg | 371 | 369 | 368 | 368 | 2.4 | 0.55 | 0.26 | 0.41 |
| Dressing percentage, % | 60.7 | 60.1 | 60.2 | 60.0 | 0.22 | 0.15 | 0.07 | 0.47 |
| Longissimus thoracis area, cm2 | 83.5 | 82.0 | 84.7 | 86.8 | 1.79 | 0.36 | 0.16 | 0.35 |
| Average fat, mm | 18.6 | 18.4 | 19.1 | 17.0 | 0.63 | 0.17 | 0.19 | 0.14 |
| Grade fat, mm | 17.1 | 17.0 | 17.8 | 15.4 | 0.68 | 0.16 | 0.20 | 0.12 |
| Marbling score4 | 24.3 | 28.1 | 33.5 | 25.3 | 4.28 | 0.40 | 0.64 | 0.16 |
| Lean meat yield, 5 % | 51.8 | 51.6 | 51.7 | 53.6 | 0.60 | 0.13 | 0.07 | 0.13 |
| Quality grade,3 % | ||||||||
| AAA | 95.0 | 92.3 | 85.0 | 97.4 | – | 0.96 | – | – |
| AA | 5 | 7.7 | 12.5 | 2.6 | – | 0.36 | – | – |
| Prime | 0 | 0 | 2.5 | 0 | – | – | – | – |
1Data are reported as least squares means with pen as the experimental unit.
2Liver abscess scores were obtained for three pens of cattle on each dietary treatment.
3Chi-square analysis was used for liver abscess score and quality grade.
4Marbling score of 60.0 to 89.9 = modest, 50.0 to 59.9 = small, 40.0 to 49.9 = slight, and 30.0 to 39.9 = traces.
5Lean meat yield, % = 57.96 − (0.027 × hot carcass weight, kg) + (0.202 × longissimus thoracis area, cm2) − (0.703 × average fat cover, mm).