Intramuscular fat content in meat-producing animals: development, genetic and nutritional control, and identification of putative markers.
By Jean-François Hocquette, F. Gondret, E. Baéza, F. Médale, C. Jurie, D. Pethick. Animal, 2010
780 citations recorded by the source corpus.
Intramuscular fat (IMF) content plays a key role in various quality traits of meat. IMF content varies between species, between breeds and between muscle types in the same breed. Other factors are involved in the variation of IMF content in animals, including gender, age and feeding. Variability in IMF content is mainly linked to the number and size of intramuscular adipocytes. The accretion rate of IMF depends on the muscle growth rate. For instance, animals having a high muscularity with a high glycolytic activity display a reduced development of IMF. This suggests that muscle cells and adipocytes interplay during growth. In addition, early events that influence adipogenesis inside the muscle (i.e proliferation and differentiation of adipose cells, the connective structure embedding adipocytes) might be involved in interindividual differences in IMF content. Increasing muscularity will also dilute the final fat content of muscle. At the metabolic level, IMF content results from the balance between uptake, synthesis and degradation of triacylglycerols, which involve many metabolic pathways in both adipocytes and myofibres. Various experiments revealed an association between IMF level and the muscle content in adipocyte-type fatty acid-binding protein, the activities of oxidative enzymes, or the delta-6-desaturase level; however, other studies failed to confirm such relationships. This might be due to the importance of fatty acid fluxes that is likely to be responsible for variability in IMF content during the postnatal period rather than the control of one single pathway. This is evident in the muscle of most fish species in which triacylglycerol synthesis is almost zero. Genetic approaches for increasing IMF have been focused on live animal ultrasound to derive estimated breeding values. More recently, efforts have concentrated on discovering DNA markers that change the distribution of fat in the body (i.e. towards IMF at the expense of the carcass fatness). Thanks to the exhaustive nature of genomics (transcriptomics and proteomics), our knowledge on fat accumulation in muscles is now being underpinned. Metabolic specificities of intramuscular adipocytes have also been demonstrated, as compared to other depots. Nutritional manipulation of IMF independently from body fat depots has proved to be more difficult to achieve than genetic strategies to have lipid deposition dependent of adipose tissue location. In addition, the biological mechanisms that explain the variability of IMF content differ between genetic and nutritional factors. The nutritional regulation of IMF also differs between ruminants, monogastrics and fish due to their digestive and nutritional particularities.
Subfields: Animal Science and Zoology, Aquatic Science, Immunology
View Paper: https://www.semanticscholar.org/paper/2ceea21353af0987d5bf6145fa2ea69c52e935cb
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Animal Science and Zoology
In Aquatic Science
Citations in the corpus
- Nutritional Composition of Meat (2018, background): “It is quite evident from the previous research that the meat having lesser connective tissues is likely to have low scores of digestion and absorption [5].”
- How Muscle Structure and Composition Influence Meat and Flesh Quality (2016, background): “In fish, the IMF content also varies between species from less than 3% in “lean” species such as cod to more than 10% in “fatty” species, such as Atlantic salmon [37], but also within species.”
- Tissue Engineering for Clean Meat Production (2019, background): “SC and fibroblast differentiation into adipocytes was also demonstrated in-vitro (Hocquette et al., 2010).”
- Growth performance, carcass traits and meat quality of bulls and heifers slaughtered at different ages (2018, background): “Indeed, sensory characteristics are often related to intramuscular fat content, especially when its concentrations are highly variable among the samples compared (reviewed by Hocquette et al., 2010).”