Histochemical identification of fiber types in canine skeletal muscle

Proximal and distal skeletal muscles from pectoral and pelvic limbs were histochemically examined in 18 neuromuscular disease-free dogs. On the basis of the human system of classification and nomenclature and results of standard adenosine triphosphatase (ATPase) and glycine-formaldehyde preincubation procedures, the fiber types identified in immature and mature canine skeletal muscles were I, IIA, and IIC.