Pig meat quality. Influence of rearing factors on skeletal muscle traits

Abstract

Pig meat quality is influenced by interactions between genotype, rearing factors and preslaughter and slaughter conditions. Genotype, particularly the presence of the major genes Hal and RN^-, and slaughter conditions greatly influence meat quality. Once influences of genotype and slaughter conditions are controlled, further improvement of pig meat quality implies to take into account the effects of rearing factors on muscle characteristics and meat quality, which is the objective of this review.

This paper describes muscle characteristics, in particular muscle fibers, intramuscular fat and connective tissue and their relationships with sensory, technological, nutritional and hygienic traits of meat. Thereafter, influences of rearing factors: age and weight at slaughter, sex, feeding level, diet composition, growth promotors, ambient temperature, exercise and rearing conditions on muscular tissue traits and meat quality are described. Although some relationships are well established, such as the favorable effect of intramuscular fat level up to 3% on sensory properties, the influence of muscle fiber characteristics (metabolic and contractile type, diameter) on the different components of meat quality is not fully understood. The identification of muscle traits that are favorable to meat quality, and a better knowledge of the mechanisms leading to the differentiation and development of muscular tissues are required, in order to produce meat that satisfies consumers as well as the meat industry.