Mateescu’s Animal Genetics and Genomics Lab is focused on research into molecular genetics for beef cattle, sheep and goats. Most biological traits of economic importance in domestic animals have a complex inheritance (are influenced by many genes and the environment) and the long-term research goal is to unravel the genetic basis for the phenotypic variability in this type of trait.
The Mateescu’s Animal Genetics and Genomics Lab is motivated by recent advances in the animal genomics field, which hold great promise for improving animal production efficiency and enhancing animal products for improved human health. Whether it is improving nutritional and health value of beef for better human health, improving resilience of sheep to environmental stressors, or increased milk production or ability to breed out-of-season in sheep, our research is directed at providing practical, industry applications.
This research contributes molecular genetics knowledge and tools, which can make a real impact in our understanding of gene regulation of biological functions, while keeping the research relevant to stakeholders and society at large.
Beef Cattle Meat Quality
The US Beef Quality audit identified low and inconsistent quality as major impediments to improving domestic demand for beef products. Consumers evaluate the quality of beef at the point of purchase with respect to freshness, marbling, and color, and at the point of consumption where the focus is on quality of eating experience, or palatability described by three sensory traits: tenderness, juiciness and flavor.
Ability to deliver a consistently superior quality product is important if beef industry is to maintain and expand its share of the market. These issues are of particular importance for Brahman and Brahman crosses as they are routinely penalized for relatively low marbling score and perceived inferior tenderness. A sustainable strategy to address these issues is via the development of effective selection and management genomic tools.
This will improve the economic position of the beef industry, improve demand for beef, increase profits and will lead to more satisfied consumers.
Beef Cattle Healthfulness Value
Beef is a highly nutritious and valued food. It is a rich source of protein and micronutrients (vitamins A, B6, B12, D, and E, iron, zinc, selenium and more). Although beef is perceived as having high fat content with undesirable composition, i.e., high percentage of saturated fatty acids (SFA), there are many nutrients in beef that have a positive effect on human health: monounsatured fatty acids (MUFA), polyunsaturated fatty acids (PUFA) such as conjugated linoleic acid (CLA) and omega-3 fatty acids, iron, zinc, magnesium.
While beef is already a good source of nutrients, the potential to further enhance its nutritional and health value is enormous. It is our contention that U.S. consumers will become increasingly supportive of food sources that they believe help them live a healthier life.
Ongoing research is focusing on characterizing the nutritional and health value of beef from Bos Indicus influenced cattle. The goals are to determine the extent to which phenotypic variation is controlled by genetics and to develop genomic tools that will allow identification of genetically superior animals with respect to these traits and use this information for selection, management and marketing.
Beef Cattle Thermotolerance
Climatic stress is a major limiting factor of production efficiency in beef cattle in tropical and subtropical environments and in dairy cattle throughout most of the world. This stress is expected to increase due to climate change. More than half of the cattle in the world are maintained in hot and humid environments, including about 40% of beef cows in the US. Substantial differences in thermal tolerance exist among breeds and among animals within breeds indicative of opportunities for selective improvement. For example, Bos indicus cattle exhibit increased resistance to many environmental stressors relative to Bos taurus, but tend to have slower growth, lower fertility and poor meat quality as they have not been as intensively selected for these traits as specialized Bos taurus breeds.
Use of genomic tools to produce an animal with superior ability for both thermal adaptation and food production represents an energy-efficient sustainable approach to meet the challenge of global climate change.
Resilience to climate stressors
The future climate is expected to be more variable, with greater frequencies and intensities of very hot periods, drought, and floods. The current rapid rate of climate change is likely to impose overwhelming pressures on the existing adaptation capacity of ruminant livestock raised outdoors. Our long-term goal is to provide necessary knowledge and tools to improve resilience of sheep to environmental stressors. The central hypothesis is that adaptation to environmental pressures is largely based on genetics and considerable variation exists among and within current sheep populations.
Whole-genome genotyping using the 60K SNP chip will allow us to identify genomic loci with adaptive significance through landscape genomic analysis; identify QTL controlling adaptation to environmental stressors through an association mapping analysis by combining the 60K SNP ecotypes and resilience phenotypes; estimate genetic breeding value for resilience traits and evaluate accuracy of values using a four-fold cross-validation approach; and develop a targeted SNP panel.
This project will facilitate development and implementation of effective breeding programs using selection as well as crossbreeding to bring about continuous and cumulative improvement of adaptive capacity for enhanced genetic resilience to climatic stressors.