This volume brings together cutting-edge research and critical reviews on the role of molecular markers in advancing animal science. From fundamental principles to applied strategies, the chapters explore how molecular diagnostics and marker-based approaches are reshaping our understanding of animal systems, disease resistance, and environmental interactions. Key themes include:· Applications of molecular markers in animal systems and diagnostics. · Genetic diversity analysis of animal genomes through marker studies. · Identification and application of resistance markers against infectious pathogens. · Nutritional influences on molecular markers and their implications for disease prevention. · Integration of molecular markers into environmental risk assessment, particularly in the context of heavy metal contamination. · Omics-based insights into contamination and molecular signatures. · Biomarker discovery—approaches, challenges, and opportunities. · Microsatellite studies reflecting genome-wide diversity. · Biomolecular indicators shaping the future of animal science. By combining theoretical insights with practical applications, this book provides a comprehensive resource for researchers, academicians, and professionals in biotechnology, veterinary sciences, and environmental biology. It emphasizes not only the scientific rigor of molecular marker studies but also their transformative potential in addressing global challenges in animal health, food security, and sustainable ecosystems.