Skeletal muscle

Skeletal muscle is the largest tissue in the body, constituting about 40% of its mass. This chapter covers the development and growth of avian skeletal muscle, beginning with a discussion of its structural diversity in different bird species, muscle fiber types, and the mechanism of skeletal muscle contraction. An overview of embryonic and posthatch development is then provided, with a focus on satellite cells, the adult myoblast stem cells that are responsible for all posthatch muscle growth. This is followed by a description of the roles of myogenic transcriptional regulatory factors and growth factors in muscle myogenesis. New emerging areas in avian skeletal muscle biology are addressed, including satellite cell heterogeneity, myopathies in meat-type poultry, and the association of these diseases with extracellular matrix organization and regulation. New strategies to combat the myopathies are discussed.