The role of environmental stress in fish health: A review

Fish are regarded as a crucial indicator of alterations in the aquatic environment due to their position at the apex of the food chain. Monitoring these alterations is crucial for identifying modifications in the aquatic ecosystem. The principal elements influencing fish health are temperature, pH, dissolved oxygen, salinity, pesticide contamination, microplastics, and algal presence. These elements substantially influence fish health regarding development, reproduction, respiration, oxygen stress, and the internal enzymes associated with digesting and other metabolic functions. Alterations in global environmental conditions and anthropogenic pollutants result in modifications to fish populations, their lives, and their behavior and mobility, therefore directly or indirectly affecting the world economy and overall environmental equilibrium.  This study presents a comprehensive analysis of the environmental alterations and determinants influencing fish health. It aims to elucidate impending environmental issues impacting fish, necessitating the development of methods and strategies to deal with these changes.