Genetic variability of muscle biological characteristics of young Limousin bulls

Abstract

Genetic parameters of 4 muscle biological characteristics (protein to DNA ratio (Pro/DNA), lactate dehydrogenase (LDH) activity, isocitrate dehydrogenase (ICDH) activity and the proportion of type I myosin heavy chains (MHC I)), in the Semitendinosus and the Longissimus thoracis, were estimated simultaneously with average daily gain (ADG), 480-d final weight (FW), carcass lean and fat contents (CL% and CF% respectively) in a sample of young Limousin bulls tested in station. The data came from 144 animals, the progeny of 15 sires. Sire and residual variances and covariances were estimated using an expectation maximization restricted maximum likelihood (EM-REML) procedure applied to a multitrait mixed model. Heritability coefficients of production traits, ADG, FW, CL% and CF%, were 0.19, 0.49, 0.39 and 0.43, respectively, while heritability coefficients of muscle characteristics, Pro/DNA, LDH, ICDH and MHC I, were 0.11, 0.26, 1.03 and 0.35 respectively, in the Semitendinosus muscle and 0.29, 0.31, 0.28 and 0.41, respectively, in the Longissimus thoracis muscle. In both muscles, the oxidative activity of the ICDH appeared to be genetically associated with the proportion of type I myosin heavy chains and opposed to the glycolytic activity of the LDH. The LDH activity was clearly associated with higher muscle-to-fat ratio, while the opposite relationship was observed between that ratio and the ICDH activity or the MHC I proportion. beef cattle / genetic parameter / growth / carcass / muscle characteristics Résumé-Variabilité génétique de caractéristiques biologiques du muscle chez des taurillons Limousins. Les paramètres génétiques de 4 caractéristiques biologiques-le

Selection for reduced muscle glycolytic potential in Large White pigs. II. Correlated responses in meat quality and muscle compositional traits

“…The only estimate found in the literature is a value of 0.46 for the heritability of LDH activity [38], but the muscle involved was not clearly specified. In other species, heritability values for LDH activity were of medium magnitude: 0.28 in cattle [28] and 0.26 in mice [22]. Results on isocitrate dehydrogenase activity in cattle [28] suggested that the heritability of muscle oxidative enzyme activities could depend on the metabolic type of the muscle, and this pattern was also found here for CS activity which was more heritable in 'red-type' than in 'white-type' muscles.…”

“…In other species, heritability values for LDH activity were of medium magnitude: 0.28 in cattle [28] and 0.26 in mice [22]. Results on isocitrate dehydrogenase activity in cattle [28] suggested that the heritability of muscle oxidative enzyme activities could depend on the metabolic type of the muscle, and this pattern was also found here for CS activity which was more heritable in 'red-type' than in 'white-type' muscles. Heritability values for myofibre percentages were much higher than the previous estimates (0.14 to 0.16) [7].…”

Heritability of percentage of fast myosin heavy chains in skeletal muscles and relationship with performance

“…human, cattle, pig, sheep and mouse). of the MHC 1 percentage in Limousin bulls was estimated at 35% (0.27) in the semitendinosus and 41% (0.28) in the longissimus thoracis muscle (Renand et al 1995). The heritability found in the present study was lower than performance values in gallop racing 25% (Langlois et al 1996) or show jumping 20% (Tavernier 1986).…”

Assessment of cattle inter‐individual cluster variability: the potential of continuum data from the farm‐to‐fork for ultimate beef tenderness management

“…Although no breed effect was found in this study, the inconsistencies would be assigned to the use of continental breeds, which differ on their maturity and typology compared to British breeds . The source of variation would be partly due to genetic variability that was not controlled in this trial, but it is known to affect both animal and growth performance as well as their carcass traits …”

“…Furthermore, previous studies reported that there is a large individual variation in beef tenderness within animals and also between animals with similar breed, sex, age and fattening system. Earlier studies at the breed or muscle level have shown that the genetic effect alone cannot explain the observed differences in carcass and meat traits because the genetic control was weak within breeds . In this context, the main objective of the beef sector is a better understanding of the variability existing between or within individuals.…”