Effect of Preslaughter Shackling on Stress, Meat Qu ality Traits, and Glycolytic Potential in Broilers

Abstract

The aim of this study was to investigate the effect s of preslaughter shackling durations on some blood parameters, breast and thigh meat qua lity traits, and muscle metabolites in broilers. The effects of shackling were determined in a group of Ross 308 broilers (240 birds) aged 42 days. Four shackling treatments were used in experimental tests: shackling of broilers for 10 (Group G 10 ; as control), 30 (G 30 ), 60 (G 60 ), and 120 seconds (G 120 ). Results showed that corticosterone (CORT) level (23 14.79 pg ml -1 ) at 120 seconds shackling group increased (P< 0.01). Results indica ted that kinase (CK) activity was the highest (2265.69 U I -1 ) in the 120 seconds shackling group while it was t he lowest (1970.64 U I -1 ) in 10 s group according to the shackling duration (P< 0.05). The breast meat redness value increased due to increase in shacklin g duration (P< 0.05). It was revealed that shackling duration had decreased breast muscle glycogen level in all treatment groups (P< 0.001). Conversely, breast lactate level increased according to increase in shackling duration (P< 0.05). It was revealed that there was a negative relationship (r= - 0.466) between breast meat ultimate pH and cooking loss (CL) value in male broilers (P< 0.01). These results indicated that the preslaughte r shackling procedure might be a considerably stressful procedure for broilers, part icularly exceeding 60 s. This study suggested that broilers could be at disadvantage du e to more struggle during long duration shackling and accelerated postmortem glyco lysis, which is detrimental to the quality of breast meat. Keywords: Creatine kinase activity, Corticosterone, Glycogen level, Lactate level, Wing flapping .