Application of haematology parameters for health management in fish farms

Abstract Farmed fish are a promising source of high‐quality and sustainable protein. However, the production of farmed fish products that meet food safety standards is one of the major public health challenges worldwide. Therefore, food safety management in fish farms has recently garnered increasing attention. However, the detection of health parameters in fish is currently lacking. Haematology, an approach that is widely used in humans, provides a reliable assessment of health status in a non‐lethal and low‐cost way. Nevertheless, comprehensive, systemic and standard haematological parameters have not yet been established in farmed fish. Here, we provide a summary of the recent advancements in haematology health indicators in fish. Generally, haematological parameters are based on physiological and biochemical indices in blood. After a global review of haematology in fish, we analysed the research progress and current trends in haematology indicators in farmed fish, and explored their potential application for healthy farming. Furthermore, we discuss the internal and external environmental factors that also affect blood physiological and biochemical indices. Finally, we discuss the trends and future challenges for the application of haematology in fish. Collectively, the topics discussed in this review highlight the predictive and severely underrated value of haematological parameters in fish farming.