Semitendinosus Muscle Development in Fetally Decapitated Pigs

Abstract
The effect of decapitation on semitendinosus muscle growth and development was studied in the fetal pig. Pig fetuses were decapitated at 45 d of gestation and histochemical and biochemical analyses conducted at 110 d of gestation. Decapitation prevented or delayed the conversion of secondary fibers from Type II to Type I histochemistry as is characteristics of the normal semitendinosus. Morphological analyses indicated either a prolonged stage of secondary myofiber formation or an inhibition of secondary myofiber hypertrophy in muscle from decapitated fetuses. Biochemical and histochemical analyses indicated that muscle from decapitated fetuses was biochemically and chemically immature compared with that from normal fetuses. Copyright © 1982. American Society of Animal Science . Copyright 1982 by American Society of Animal Science.