Abstract
For many years, variation in carcass and meat quality traits was thought to result from actions taken throughout the animals’ life after birth. However, the quantity and quality of meat obtained at slaughter are not always as good as expected. The past decade has increased the number of evidence of the effects of intrauterine development of skeletal muscle on animal performance that affects the carcass and meat quality traits. The so-called “Fetal Programming” concept sheds light on the biology of skeletal muscle development in meat animals, revealing that this development stage appears to be a pivotal moment to invest efforts aiming to improve animal productivity and the quality of meat. Because most, if not all, of the muscle fibers are formed prenatally in livestock species, the impairment of muscle fiber formation at this stage will limit the overall muscle mass deposition throughout postnatal life. Intramuscular adipocytes also start their formation at the fetal stage. As such, since the intramuscular fat depot has a lower deposition rate than other fat depots, enhancement of intramuscular adipogenesis during the fetal stage may increase marbling deposition postnatally. Muscle fibers, adipocytes, and fibroblasts, which contribute to connective tissue formation, are derived from the same pool of mesenchymal stem (MS) cells. Depending on the insult suffered during intrauterine development, their commitment may shift from myogenic towards adipogenic/fibrogenic lineage. So far, most of the evidence in livestock animals has shown that maternal nutrition during gestation is the main factor that influences the mechanisms underlying the commitment of the MS cells. Although the majority of these studies have shown the consequences of maternal nutrition on myogenesis, adipogenesis, and fibrogenesis, the epigenetic markers that cause the programming of MS cells to undergo to one lineage or another needs to be further investigated.
Multi-breed and multi-trait co-association analysis of meat tenderness and other meat quality traits in three French beef cattle breeds
