title: Inter-animal variation in the biological characteristics of muscle tissue in male limousin cattle.
abstract: The biochemical, metabolic and contractile characteristics of semitendinosus (ST) and longissimus thoracicus (LT) muscles were studied in 147 male Limousin cattle. The animals, which were slaughtered at 16 months, were the offspring of 15 different sires. Weight gain and carcass tissue composition (proportion of muscle and adipose tissue) were also measured. The biochemical characteristics of the two muscles studied had coefficients of variation between 13 and 30% markedly higher than for proximate characteristics of the carcass, in which coefficients were all lower than 18%. There were significant differences between the two muscles: ST had a higher protein/DNA ratio and greater lactate dehydrogenase (LDH) activity than LT, also a lower isocitrate dehydrogenase (ICDH) activity and lower slow myosin heavy chain (MHCI) content. The percentage of MHC 1 was positively correlated with ICDH activity and negatively with LDH activity and protein/DNA ratio. These muscle characteristics were also correlated with weight gain: animals with greater weight gain had a higher protein/DNA ratio and lower oxidative activity, with differences in the level of significance of the correlations according to muscles. Selection of animals on the basis of muscle growth may therefore be a means of improving the quality of meat.
authors: Laboratoire Croissance et Métabolismes des Herbivores, U.R. Croissance Musculaire, INRA, Centre de Clermont-Fd/Theix, 63122 St-Genès Champanelle France.
authors: C
authors: C
authors: Jurie
authors: J
authors: J
authors: Robelin
authors: B
authors: B
authors: Picard
authors: G
authors: G
authors: Renand
authors: Y
authors: Y
authors: Geay