Ontogenesis of muscular characteristics in the rabbit. Effects on meat quality

Abstract

Muscle characteristics are involved in many aspects of meat quality. The aim of this paper is to present the differentiation, growth and variations of the main muscular characteristics in the rabbit.

Rabbit muscles are very immature at birth. Postnatal life is characterized by an increase in the fiber size, leading to an increase in the muscle weight. Dramatic changes affect the contractile fiber types during all the first postnatal month. Differentiation of the metabolic fiber types takes place during this period and continues until 2 months of age.

During the post-weaning period, intramuscular lipids increase with age. This increase is mainly associated with changes in triglyceride content stored in adipocytes clustered along the myofibers. The ontogeny of intramuscular adipocytes takes place during the perinatal period. Thereafter, both adipocyte number and adipocyte size increase until 5 months of age.

Genetic and rearing factors can influence the muscle characteristics. However, only manipulations "in utero" or during the lactation period seem to be able to influence muscle fiber development and intramuscular fat development together.