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Impact of mechanical vs. manual catching on stress, fear, and carcass quality in slower growing broilers
Kristofer C Smith1, Meghann K Pierdon1
1Clinical Studies, University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA, USA.
Abstract:
This study evaluated manual and mechanical catching methods on slower growing broiler chickens on the day of processing. Ten catching events, five mechanical and five manual, were evaluated for animal welfare and an additional set of 241 catches, 128 manual and 113 machine, were analyzed to determine the effect on carcass quality. No significant difference in serum corticosterone concentration (CORT) was found between the catching methods (p = 0.9). Pre-catching CORT (15.07 ± 2.24) was significantly lower than post-catching (25.41 ± 2.22) (p < 0.001). Manually caught broilers had four times greater odds of tonic immobility (TI) than mechanically caught birds (OR 4.0, 95% CI: 1.54-10.54) (p < 0.001). Birds also had 77% lower odds of TI before being caught than after, irrespective of catching method. Manually caught birds had 19% greater risk of bruised wings (p < 0.05) and 23% greater risk of bruised legs (p < 0.05). Lower odds of TI and decreased risk of injury in the machine caught birds indicate improved welfare and carcass quality compared with manual catching. Overall, machine catching was found to improve welfare and carcass quality in these slower growing broilers.

