Histological features, morphometric traits and meat quality of broilers with myopathies in a low-input commercial abattoir

Wooden breast, white striping, spaghetti meat and green muscle disease are myopathies that occur on the breast muscles of broilers due to their rapid growth during rearing. These myopathies are characterized by histological changes and negatively affect the quality of broiler meat, thus leading to economic losses. The aim of the study was to determine the histological features of broiler meat with myopathies and the influence of myopathies on morphometric traits and meat quality characteristics of the breast muscles. Data were collected from 80 broiler breast fillets, which underwent macroscopic examination 24 hours post-slaughter, followed by histological analysis of a subset (n = 46). Physicochemical indicators (pH and temperature), meat color, water holding capacity, as well as morphometric traits (weight, width, length and thickness) were determined in all breast muscle samples. Macroscopic examination of breast muscles revealed the presence of myopathies in 50/80 (62.50%) broilers. Wooden breast was identified in 22.50% (n = 18) of broilers, white striping in 13.75% (n = 11), spaghetti meat in 16.25% (n = 13), while green muscle disease was detected in 10.00% (n = 8) of the birds. Histological analysis of broiler breast muscles affected by myopathies revealed degeneration and necrosis, hypereosinophilia, loss of cross-striations, sarcoplasmic vacuolization, fiber fragmentation and the presence of inflammatory cells. Broilers with myopathies had significantly lower breast muscle weight compared to individuals without myopathies. The presence of myopathies negatively affected meat quality characteristics, in terms of high ultimate pH, inadequate water holding capacity (lower thawing and cooking loss) and unfavorable meat color (too high or low L+ value). In conclusion, meat from broilers affected by any of the studied myopathies does not fulfill the standards for market placement and is suitable only for processing into lower-quality meat products.