Applications of solid-state fermented (SSF) diets to improve the growth, organ health, immunity and disease resistance through modulating the transcriptomics and proteomics profile in fish and shrimp.

Fish meal (FM) has long been used as a staple protein source in aquafeed owing to its balanced amino acids, excellent feed conversion, and improved palatability and digestibility. However, the use of FM in aquafeed formulation is facing difficulties due to concerns regarding availability, price, overfishing, and sustainability. Thus, there is a growing interest in seeking alternative protein sources from plant and animal by-products to partially or fully replace FM in aquafeed. Challenges such as lower nutrient bioavailability, high antinutritional factors, indigestible materials, microbial contaminants, and lower palatability issues have limited the incorporation of these protein sources into aquafeed. The application of solid-state fermentation (SSF) strategy represents a sustainable method to address these problems by improving aquafeed quality and introducing health-promoting beneficial microbes. Moreover, numerous studies have shown that SSF enhances growth, feed utilization, health status, immune system, and disease resistance in aquaculture species. At present, molecular approaches such as transcriptomics and proteomics techniques are widely used tools for evaluating the impacts of SSF on fish and shrimp. They provide valuable insights into the mRNA transcripts and proteomes related gene expressions associated with growth, immunity, and stress response. In this article, we outline the requirements for SSF and discussed its role in ameliorating growth, health, immunity, and disease resistance in farmed species. We also provide up-to-date information about the utilization of SSF technology to modulate the transcriptomics and proteomics profiles in fish and shrimp. The complied evidence aims to support future research efforts and encourage the development of fermented feed as a functional dietary option for promoting sustainable aquaculture practices.