PSIII-20 - The Effect of Waiting Time at the Lairage of Slaughterhouse of Fattening Bulls After a Long Transport on Animal Behavior, Carcass Quality and Meat Quality

Abstract: The aim of this study was to evaluate the effect of waiting time at the lairage before slaughter in crossbred bulls after a long transport (~14h). One-hHalf of the bulls of each transport (n = 8 transports; n = 48 ± 4 bulls/transport) were distributed in two treatments: short waiting time (SWT; < 2h; n = 179) and long waiting time (LWT; from 7 to 8h; n = 165). Animal behavior was recorded during waiting time at the lairage. The pH in Longissimus dorsi (LD) between 30 and 36 h postmortem, was registered and a subset of 24 LD were selected for meat quality evaluation. Each loin was cut in 5 slices, one to determine instrumental color, and the others were disposed in high oxygen modified atmosphere packaging (MAP) to evaluate instrumental color, microbiology, and color stability between d 1 to 12. Data were analyzed using mixed models with repeated measures. Animals standing with LWT treatment decreased (P< 0.001) after the first hour at the lairage (71% to 32%, between 1h and 2h, respectively). After 3h, standing time and non-nutritive oral behaviors started to increase until sixth hour at the lairage (63%). Meat pH was lesser (P < 0.01) for SWT (5.6 ± 0.05) compared with LWT (5.7 ± 0.05). However, the percentage of carcass classified as DFD (pH > 5.7) did not differ between treatments. Meat redness (a*) and yellowness (*b) at 30-36 h were greater (P < 0.05) for SWT (16.3 ± 0.94 and 16.7 ± 1.53, respectively) compared with LWT (15.1 ± 0.94 and 15.6 ± 1.53, respectively). The increase of activity after 3 h at the lairage could be related to the long fasting hours caused by a long transport, however after a long transport waiting time at the lairage had minimal detrimental effects on meat quality.