A recent study published in Aquaculture Research explored a novel approach to address the dependency on fishmeal and fish oil in feed production for the aquaculture industry.
Researchers from Fondazione COISPA ETS, the Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), IRIDA S.A., Ifremer, among other academic organizations, studied the impact of a sustainable and cost-effective diet on the growth, health, and welfare of gilthead sea bream (Sparus aurata), a popular Mediterranean marine aquaculture species. This innovative diet replaced 60% of fishmeal with a blend of plant ingredients, yeast, and krill meal.
New Feed Ingredients: A Promising Solution
In recent years, research has been conducted to identify new feed ingredients that can substitute fishmeal and fish oil in aquaculture feed. Plant protein sources, such as soybean meal and pea protein, have shown promising results in diets for both herbivorous and carnivorous species.
On the other hand, single-cell ingredients like yeast are also gaining attention due to their rapid growth, high protein content, and renewability. Additionally, alternative ingredients from terrestrial or marine animal sources, such as Antarctic krill meal, have been proposed as potential substitutes for fishmeal.
Blending Alternative Protein Sources: A Cost-Effective Solution
To overcome the limitations of using a single alternative protein source, blending complementary protein sources has been suggested as an appropriate solution. This approach can provide cost-effective and sustainable diets while ensuring highly balanced nutrition.
Moreover, recent advances in biotechnology, such as fermentation technology, have also reduced the anti-nutritional elements in plant ingredients and increased their protein content.
Balancing Nutrition and Welfare
While innovative feed ingredients offer promising solutions, it is essential to ensure they meet the specific nutritional needs of fish species. A balanced diet is crucial for optimal growth, health, and welfare. Additionally, the impact of these alternative ingredients on fish behavior, physiology, and immune function must be carefully monitored.
Feeding Trial
The innovative diet, which replaced 60% of fishmeal with a blend of plant ingredients, yeast (Saccharomyces cerevisiae), and krill meal, was compared with a commercial diet (control) over a 135-day experiment.
The researchers evaluated various parameters, including growth performance, stress-related physiological blood parameters, immunity, health and welfare, as well as swimming activity, which served as an indicator of energy expenditure.
Key Findings
- Improved Growth: Fish fed the innovative diet showed significantly better growth compared to those fed the control diet.
- Enhanced Immune Function: Higher levels of Immunoglobulin M (IgM), a key antibody involved in humoral immunity, were observed in the plasma of fish fed the innovative diet. This suggests that the diet may stimulate the immune response of fish, helping them better combat diseases and infections.
- Higher Energy Expenditure: Accelerometer tags revealed that fish fed the innovative diet exhibited greater overall swimming activity. This higher energy expenditure was also reflected in higher levels of prealbumin, a protein associated with energy metabolism.
- No Adverse Effects on Welfare: Despite the higher energy expenditure, the researchers found no evidence of impaired welfare in fish fed the innovative diet. Hematological and biochemical indicators remained within normal ranges.
The Future of Sustainable Aquaculture
These promising results highlight the potential of innovative feed formulations to reduce dependency on fishmeal and fish oil while maintaining or even improving fish health and performance. However, further long-term studies are needed to fully evaluate the long-term impacts of this diet on fish health, reproduction, and environmental sustainability.
By adopting sustainable feeding practices and innovative technologies, the aquaculture industry can contribute to a more sustainable future for seafood production.
Conclusion
The search for sustainable aquaculture feeds is a crucial issue for European marine fish farming. Innovative and environmentally friendly solutions, such as new feed ingredients and the combination of alternative protein sources, can help reduce the industry’s reliance on fishmeal and fish oil.
This study provides a comprehensive assessment of the physiological status of gilthead sea bream under innovative nutrition, addressing the environmental sustainability challenges of European aquaculture.
The study was funded by the H2020 FutureEUAqua project.
Contact
Lola Toomey
Fondazione COISPA ETS
Bari, Italy
Email: toomey@fondazionecoispa.org
Reference (open access)
Alfonso, S., Toomey, L., Fiocchi, E., Manfrin, A., Boscarato, M., Vasilaki, P., Zupa, W., Bertazzo, V., Bégout, L., Spedicato, M. T., Mente, E., Nengas, I., Lembo, G., & Carbonara, P. (2024). Growth Performance, Immune Characteristics, and Health and Welfare of Gilthead Seabream (Sparus aurata) Fed a Tailor-Made Environmentally Sustainable Diet Formulated Using Novel Ingredients. Aquaculture Research, 2024(1), 8234882. https://doi.org/10.1155/2024/8234882
