Relationship of Broiler Bruise Age to Appearance and Tissue Histological Characteristics

Because commercial broilers may be bruised at any time during production and even up to the time of slaughter, minimizing bruising requires a clear understanding of when and how it occurs. The present study was conducted to investigate the relationship between the age, visual appearance, and histological characteristics of a bruise. Market-aged broilers were anesthetized, bruised on the breast, wing, and drum, and processed 0, 1, 6, 12, or 24 hr after receiving the bruises. Bruise color measurements revealed that as their age increased, breast bruises became darker (higher ΔL; changes in lightness value), whereas wing and drum bruises became lighter (lower ΔL). Redness and yellowness of breast bruises were not significantly different at any of the bruise ages. With increasing bruise age, wing bruises became less red and less yellow, and drum bruises became more red and more yellow. Histological tissue samples showed that drum bruises were more severe than breast or wing bruises at all time intervals. For all bruises, maximum ΔL and tissue edema occurred in carcasses of broilers injured 6 hr before processing.