FROM GENETIC DIVERSITY TO BREEDING INDICES: STUDIES IN LOCAL AND COSMOPOLITAN CATTLE POPULATIONS

This thesis is organized into a general introduction, four experimental chapters, and a final chapter providing overall conclusions. Chapter 1 introduces local and cosmopolitan cattle breeds and reviews the main statistical and genetic approaches used to investigate biodiversity and genetic relatedness among local populations, as well as economically relevant traits and validation methods for genetic indices in cosmopolitan breeds. Chapters 2 and 3 focus on local cattle breeds. Chapter 2 investigates genetic diversity among Spanish cattle populations and subpopulations, whereas Chapter 3 examines the shared genomic background among three local Sardinian cattle populations. Chapters 4 and 5 address quantitative genetics in cosmopolitan cattle populations. Chapter 4 proposes a fertility index for Italian Jersey cows, while Chapter 5 evaluates the application of a novel approach for validating genetic indices in beef cattle. Finally, the concluding chapter summarizes the main findings from the four experimental studies and discusses their broader implications.