From farm to slaughter: broiler welfare assessment during catching, loading, transport and lairage

The transport process (starting with catching on farm and ending with unloading and lairage at the slaughter plant) is a critical and stressful phase of the production process, with potentially serious animal welfare and economic implications. This study’s aim was to assess the impact of various phases of the transport process (catching/loading, transport and lairage), and their related risk factors, on broiler welfare. A protocol with 19 animal-based measures was used to assess broiler welfare during transport, with measures based on EFSA recommendations and Welfare Quality®. Welfare was assessed for 82 transports from 52 commercial farms (flock size range 13,750-160,000) to five slaughter plants in Belgium. Each transport was assessed at four moments: on farm before catching/loading, on farm after catching/loading, at the slaughter plant during lairage, and after slaughter. Data were log-transformed (except for body weight and temperature) and analysed in SAS using PROC MIXED and GLIMMIX with farm as a random effect. Results are shown as mean±SE. Broilers lost 5.3% of their weight during transport (2.65±0.01kg before catching, 2.51±0.01kg after transport; P<0.001). Weight loss tended to increase with transport duration (43±22g loss/h, range 0.5-5h; P=0.074). Body temperature was lower after transport compared to after catching/loading (40.5±0.01°C vs. 41.2±0.01°C; P<0.001). The prevalence of birds with wing fractures was higher after catching and loading than before catching (1.75% vs. 0.08%; P<0.01). Dead on Arrivals (DOAs) were affected by type of catch crew: fewer DOAs were found when the birds had been caught and loaded by a professional team compared to a team consisting of friends or family (0.23±0.03% vs. 0.46±0.12%; P=0.001). There were fewer carcass rejections at slaughter when transports occurred at night (0.49±0.05%) compared to morning (1.07±0.24%; P=0.025) or daytime (1.42±0.33%; P<0.001). Each increase of ambient temperature with 1°C (range 0.1-25.7°C) resulted in a 1.21-fold increase of broilers with bruised legs (P=0.037) and a 1.02-fold increase of broilers with bruised breasts and wings (P=0.027). No significant associations between the lairage phase and welfare parameters were found in this study. To conclude, a number of risk factors (transport duration, type of catchers, moment of transport, ambient temperature) were identified for weight loss, DOAs, carcass rejections and bruises. Also, critical transport phases (catching/loading and transport) for body temperature and fractures have been identified.