Spotlight on avian pathology: current growth-related breast meat abnormalities in broilers.

Selection for fast-growing and high-breast-yield hybrids has enormously increased the pressure on muscle development rate and mass, indirectly promoting the development of muscular abnormalities affecting the pectoral muscles such as White Striping, Wooden Breast and Spaghetti Meat. Macroscopically, the muscles affected by these defects exhibit distinctive traits, whereas the microscopic examinations evidenced similar histological alterations. Therefore, a common causative mechanism (involving genes related to several metabolic pathways and functional categories) underpinning the occurrence of these abnormalities may be hypothesized and directly associated with muscle hypertrophy induced by selection. Within this context, as the occurrence of growth-related abnormalities may negatively affect consumer attitude and certainly leads to considerable economic losses, resulting from meat downgrading, it clearly emphasizes the need to consider those issues related to muscle growth and meat quality when selecting meat-type genotypes.