This book provides a concise yet comprehensive guide to physiological techniques in finfish and shellfish. Covering key areas such as oxygen consumption, nitrogenous waste excretion, hematology, biochemical analysis, and histology, it serves as a valuable resource for students, researchers, and professionals in fisheries science and aquaculture. Each chapter offers step-by-step methodologies based on internationally recognized techniques, ensuring accuracy and reproducibility in research and industry applications.'