The Invisible Balance: How Prebiotics and Probiotics Can Support Fish Health and Development

Aquaculture is a field that has developed rapidly over the past decade with the emergence of intensive farming systems that have significantly increased global fish production. However, this intensification has also led to the emergence of diseases caused by various pathogens, often resulting in extensive antibiotic use and, consequently, antimicrobial resistance (AMR). Consequently, research has focused on finding other sustainable alternatives to avoid the overuse of antibiotics and to protect both human and animal health. Probiotics and prebiotics have been extensively studied for their wide range of effects on growth, immunity, and the control of various pathogens. Through their complex mechanisms, they can also improve water quality, mitigate the effects of various physicochemical stressors, and enhance reproduction. This review aims to present the evolution of these concepts, with an emphasis on their effects, which often vary depending on the type of additive used, the dose, and the fish species.