Phytochemicals: Essential Oils and Other Extracts for Disease Prevention and Growth Enhancement in Aquaculture: Challenges and Opportunities.

This review explores the potential of essential oils (EOs) as natural feed additives in aquaculture, highlighting their antimicrobial, antioxidant, and immunostimulatory properties, which contribute to disease prevention and improved fish resilience. EOs, derived from aromatic plants, offer a sustainable alternative to synthetic chemicals, promoting benefits such as enhanced growth rates, feed efficiency, immune function, and reduced pathogen susceptibility. However, several challenges must be addressed to fully unravel their potential, including the optimization of dosages, effective delivery methods, and cost-efficiency. Techniques such as microencapsulation are emerging as promising solutions to improve EO stability and controlled release in aquatic feeds, though further research is needed to refine these approaches and evaluate their scalability. Additionally, there is a need for more research into the mechanisms through which EOs influence fish health, the interactions between active compounds, potential synergistic effects of EO mixtures, and their impact on the aquatic environment and microbiome. Addressing these challenges will ensure the effective and sustainable application of EOs in aquaculture, reducing reliance on synthetic chemicals while fostering a more resilient and eco-friendly industry. A key feature of this review is the systematic presentation of detailed, species-specific tables summarizing the current literature on the application of EOs and plant extracts in fish health management.