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

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-half 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.