Molecular Genetics-Nutrition Interactions in Ruminant Fatty Acid Metabolism and Meat Quality

This chapter deals with our experience with inquiry-based, student-focused teaching and research approach to genetics-nutrition interactions in ruminant livestock at the University of Tasmania. An in-depth literature review on the manipulation of muscle and adipose tissue fatty acid composition and molecular marker associations with meat quality is also presented. Examples of our laboratory practicals on intramuscular fat extraction,fat melting point, meat quality and molecular genetics techniques in gene sequencing homology are also included. Since the 1960s, it was already known that nutrition was among the most significant environmental factors regulating the action of genes and the subsequent exhibition of phenotypes in animals (Jacob and Monod, 1961). Ordovas (2008) concluded that it is of paramount importance that genes are considered in the context of nutrition and that nutrition is considered within the context of genes.‚ÄövÑvp This notion is the foundational building block of the concept of genetics-nutrition interactions in molecular genomics. In other words, genetics-nutrition interaction describes the modulatory effect of a dietary component on a specific phenotype by a genetic variant. Alternatively, this notion refers to the dietary modification of the effect of a genetic variant on a phenotypic trait. However, the mechanisms responsible for individual and breed-specific differences in dietary responses are very complex and poorly understood. This lack of understanding necessitates a comprehensive examination of genetics-nutrition interactions in livestock at the molecular level, to unravel the role of genetic factors contributing to differences in response to supplementary nutrients for the metabolic alterations of fatty acids that affect meat quality. A major dilemma that undergraduate students face in animal science is understanding the complex scientific concepts of genetics by nutrition interaction relationships in pasture-based systems obtainable in the sheep, dairy, and beef cattle industries (Malau-Aduli et al., 2012a). It has been suggested that in order to challenge old assumptions and break new ground in teaching and learning in the animal sciences, a paradigm shift from the traditional teacher-focus to a modern student-centered learning approach is necessary for establishing synergy (systematic working together in concert) between research-led teaching and inquiry-based learning to enhance students'understanding of both science content and scientific practices (Malau-Aduli and Lane, 2012). Australian data conclusively demonstrated that the implementation of an innovative, inquiry-based learning, and research-led teaching approach made a significant contribution to the student learning experience in animal science through the development of students' critical thinking and scholarly values of genetics-nutrition interactions in livestock (Malau-Aduli et al., 2012a). This strategy in addition to the theoretical concepts taught in class, included student exposure to hands-on genetics-nutrition experimental growth trials with sheep (Holman and Malau-Aduli, 2012a,b, Holman et al., 2012, Malau-Aduli and Akuoch,2012, Malau-Aduli and Holman, 2010, Malau-Aduli et al.,2012b), laboratory experiments on intramuscular fat extraction,fat melting point, sensory evaluation of meat eating qualities,statistical data analysis, livestock industry field visits, scientific journal article critiques, and seminar presentations.