Wiktoria Kościów, Emilia Lisiecka, Monika Łukasiewicz Mierzejewska
Modern broiler chickens have been selected for very rapid growth, efficient feed use, and a high proportion of breast muscle. However, the development of the cardiovascular and respiratory systems may not always keep pace with the increasing metabolic demands of rapidly growing tissues. This imbalance may contribute to reduced blood flow, insufficient oxygen delivery, oxidative stress, inflammation, and abnormal muscle regeneration. At the same time, environmental and management factors such as heat stress, high stocking density, poor air quality, unsuitable lighting programs, limited activity, and pre-slaughter stress can further challenge the birds' ability to maintain normal physiological function. This review explains how cardiovascular health and welfare conditions may interact in the development of breast muscle abnormalities and changes in meat quality. Particular attention is given to impaired circulation, tissue oxygen deficiency, vascular dysfunction, and their possible links with conditions such as wooden breast, white striping, and spaghetti meat. Understanding these relationships may help improve broiler health and welfare while maintaining meat quality and production efficiency. Future research should combine measurements of cardiovascular function, bird behaviour, environmental conditions, muscle health, and meat quality in the same animals over time.