by Dr Mark Rawling, Research Fellow, University of Plymouth, UK
Aquaculture has become the fastest-growing food production sector globally, supplying over half of the seafood consumed worldwide. Yet, as demand increases, so do the challenges. Aquaculture continues to face pressures from disease, environmental stressors and the need to reduce the dependence on chemotherapeutics. In this context, functional feed additives (FFAs) implemented into animal feeds are emerging as one of the most effective prophylactic strategies to improve animal health, welfare and overall productivity.
The challenge: resilience under pressure
Modern aquaculture production relies on achieving a balance between optimising growth performance and managing emerging biotic and abiotic risks. In this regard, pathogens, deteriorating water quality and climate-driven stressors such as temperature and salinity fluctuations continue to challenge production efficiency, often leading to reduced growth, higher feed conversion ratios and increased mortality. Historically, these risks were managed through the widespread use of chemotherapeutic agents. However, shifting consumer expectations and tightening regulatory frameworks have made this approach unsustainable. Today, the industry is transitioning toward more holistic, preventive health management strategies emphasising functional nutrition, biosecurity and microbiome-based interventions to build resilience and ensure long-term sustainability.
Farmers and feed companies are therefore seeking solutions that work with biology rather than against it. FFAs such as probiotics, prebiotics, immunomodulants, enzymes and other bioactive compounds are demonstrating increased efficacy in enhancing growth, immunity and feed efficiency under various conditions. Such interventions present a strategic means of maintaining fish and crustacean health. When applied correctly, these interventions can: (1) strengthen immunity, reducing susceptibility to pathogens; (2) stabilise the microbiome, supporting gut health and efficient digestion; (3) support stress resilience under fluctuating temperatures, salinity or oxygen levels; and (4) enhance growth efficiency while reducing waste outputs.
For instance, immunogenic compounds such as β-glucans derived from the yeast cell wall of Saccharomyces cerevisiae, have demonstrated the capacity to prime both the cellular and humoral components of the immune system in finfish and crustaceans, enabling a more rapid and effective response to disease challenges. Similarly, targeted probiotic strains have demonstrated the capacity to strengthen intestinal barrier integrity, modulate gut immunity and stabilise microbial communities in many commercially important aquaculture species, thereby reducing the prevalence of enteric disorders and improving overall feed performance. Likewise, the inclusion of specific exogenous enzymes such as proteases, amylases and phytases can enhance nutrient digestibility and absorption. Collectively, these scientific advancements in elucidating the mode of action of FFAs underscore a broader shift toward preventive health strategies targeted to enhance productivity and resilience in modern aquaculture systems.
From laboratory to farm: why partnerships matter
While the science of FFAs is advancing rapidly, the real challenge lies in translating research into on-farm solutions. This is where close collaboration between universities, feed manufacturers and producers is essential. Industry brings practical insight and understanding of farming conditions, supply chain realities and commercial viability. Researchers contribute the tools to test hypothesis-driven research, validate mechanisms and ensure robust evidence. Together, these perspectives create feed solutions that are not only scientifically robust but also economically feasible and applicable at scale.
Looking ahead: innovation with integrity
The future of FFAs hinges on both innovation and implementation. Greater transparency in trials, robust scientific evidence and clear communication with farmers are essential to build trust. As researchers, we must continue to ask:
1. Does the efficacy of this additive translate from controlled trials to commercial production environments?
2. How does it integrate into broader management practices on farms?
Despite significant progress, the aquaculture sector must go further to build a culture of collaboration, transparency and data sharing that accelerates innovation and drives collective progress across the entire food sector.
Partnership for progress
FFAs are not a silver bullet, but they are a crucial component of the toolkit for promoting healthier and more resilient aquaculture. By fostering partnerships across science and industry, we can ensure these innovations are not only promising in laboratory but translate to practical and impactful solutions for farmers. The opportunity before us is clear: feeds that supports growth, build resilience, enhance welfare and drives sustainability. This is a vision worth pursuing, one that will shape the future of aquaculture
