Table 3.
Carcass characteristics of cattle vaccinated against respiratory pathogens at: (i) weaning (day 0) and at feedlot entry (day 30; CON, n = 53), (ii) 15 d before weaning (day −15) and 15 d before feedlot entry (day 15; EARLY, n = 53), and (iii) 15 d after weaning (day 15) and 15 d after feedlot entry (day 45; DELAYED, n = 53)1,2
| Item3 | EARLY | CON | DELAYED | SEM | P-value |
|---|---|---|---|---|---|
| Hot carcass weight, kg | 394 | 402 | 398 | 4 | 0.47 |
| Backfat, cm | 1.88 | 1.82 | 1.86 | 0.06 | 0.80 |
| LMarea, cm2 | 92.6 | 91.8 | 92.3 | 0.8 | 0.80 |
| KPH, % | 2.07 | 2.03 | 2.02 | 0.02 | 0.29 |
| Marbling | 487 | 484 | 479 | 10 | 0.85 |
| Yield grade | 3.66 | 3.74 | 3.72 | 0.10 | 0.81 |
| Retail product, % | 48.6 | 48.5 | 48.5 | 0.2 | 0.97 |
| Choice, % | 96.0 | 97.7 | 91.6 | 3.0 | 0.35 |
1Vaccines administered were against Clostridium and Mannheimia haemolytica (2 mL subcutaneous injection of One Shot Ultra 7; Zoetis, Florham Park, NJ), bovine herpesvirus-1, bovine viral diarrhea viruses types 1 and 2, parainfluenza3 virus, and bovine respiratory syncytial virus (2 mL subcutaneous injection of Bovi-Shield Gold 5; Zoetis). Calves also received these vaccines at 45 d of age. Calves not receiving vaccination were administered 4 mL of sterile saline subcutaneously.
2Calves were maintained in a single pasture from days −15 to 30, transported (day 30) for 480 km to a commercial growing feedyard, and moved (day 180) to an adjacent finishing yard where they remained until slaughter (day 306).
3Backfat thickness measured at the 12th rib; marbling score: 400 = Small00, 500 = Modest00; 600 = Medium00; yield grade calculated as reported by Lawrence et al. (2010); USDA retail yield equation = 51.34 − (5.78 × backfat) − (0.0093 × hot carcass weight) − (0.462 × KPH) + (0.74 × LM area area).