Myofiber length and myofiber arrangement in the antebrachial and leg muscles of sheep.
The myofibers of the skeletal muscle vary in length in muscle and from muscle to muscle. Information about myofiber length and myofiber arrangement is necessary to understand the architecture of muscles and differences in myofiber length in muscles. The purpose of the present study was to determine myofiber lengths, ratio of myofiber length to muscle length, and myofiber arrangement of the antebrachial and leg muscles in the sheep. The myofibers of the antebrachial muscles ranged from 7.3 mm (m. extensor carpi ulneris, bipennate muscle) to 39.6 mm (m. flexor digitorum profundus caput radiale, unipennate muscle) in length. The myofibers of the leg muscles ranged from 10.0 mm (m. flexor digitorum superficialis, multipennate muscle) to 119.2 mm (m. soleus, fusiform muscle) in length. The ratio of myofiber length to muscle length in the fusiform muscle was higher than that in the uni-, bi-, and multipennate muscles. The unipennate muscles tended to have a higher ratio of myofibers length to muscle length than did the bi- and multipennate muscles. No difference in the ratio of myofiber length to muscle length existed between the bipennate muscles and multipennate muscles.
Konno
T
T
Department of Animal Production Sciences, Graduate School of Agricultural Science, Tohoku University, Sendai-shi, Japan.
Suzuki
A
A
D000818:Animals; D007866:Leg / Q000033:anatomy & histology; D018482:Muscle, Skeletal / Q000166:cytology*; D009210:Myofibrils / Q000648:ultrastructure*; D012756:Sheep / Q000033:anatomy & histology