Artemia (Artemia sp.), or brine shrimp, is a fundamental live feed in global aquaculture, valued for its ease of production and high protein and lipid content. However, its nutritional value has a critical limitation: the lack of highly unsaturated fatty acids (HUFA), such as DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), which are essential for the growth, survival, and immune function of fish and crustacean larvae.
To overcome this deficiency, the industry has perfected various enrichment strategies. This process involves feeding the nauplii (artemia larvae) with diets rich in specific nutrients so that they become “bioencapsulated,” meaning they are incorporated into the artemia’s body and then transferred to the cultured animals. A recent study published in Reviews in Aquaculture by researchers from the University of Arkansas at Pine Bluff and the Great Salt Lake Brine Shrimp Cooperative, Inc., delves into these strategies and their effects, offering a comprehensive perspective for professionals in the sector.
Key findings
- Artemia enrichment is essential for addressing its natural deficiency of highly unsaturated fatty acids (HUFA), like DHA and EPA, which are crucial for the development, survival, and immune health of fish and crustacean larvae.
- The choice of enrichment agent directly impacts the final nutritional profile of the artemia. While fish and squid oils are excellent for providing EPA, microalgae like Schizochytrium are superior for DHA enrichment.
- In addition to lipids, other additives such as soy lecithin, probiotics, yeasts, and micronutrients (vitamins and minerals) improve key aspects of larval health, including digestion, stress resistance, immune function, and pigmentation.
- Optimizing the process—including the duration of enrichment, feed concentration, and environmental conditions—is vital to maximize nutrient absorption by the artemia and ensure the benefits are transferred to the consuming larvae.
Enrichment with oil emulsions
One of the most common techniques is the use of oil emulsions, which are mixtures of lipid-rich oils and micronutrients dissolved in water. These emulsions are the most effective way to provide HUFA to artemia. The most used oils come from marine sources, such as fish and squid oil, which are particularly rich in EPA and DHA. However, plant-based alternatives like canola and linseed oil have also been explored; although they may be less dense in HUFA, they are a valid and sustainable option when supplemented with vitamins and antioxidants.
The success of this method depends on factors such as the size of the emulsion particles and the duration of the enrichment. Smaller oil droplets (nanoparticles) are more easily assimilated. The study indicates that an enrichment period of 12 to 24 hours is generally the most effective. A shorter time may be insufficient, while an excessively long period could lead to fatty acid oxidation, causing a loss of nutritional value.
The impact of this type of enrichment on aquatic species is notable. Larvae of fish such as sturgeon and sunfish, fed artemia enriched with oil emulsions, have shown greater growth, improved survival, and increased resistance to osmotic stress. This is vital in the early stages of life when animals are most vulnerable.
The power of microalgae
Microalgae are a sustainable enrichment source that provides not only lipids but also a range of other beneficial compounds such as carotenoids (pigments), essential amino acids, and vitamins. Some species, such as Isochrysis galbana and Schizochytrium sp., are particularly valued for their high DHA content, while others, like Nannochloropsis oculata, are rich in EPA.
The microalgae enrichment methodology can vary, using live cells, pastes, or freeze-dried products. A key aspect is the density of the algae in the culture medium. Optimal concentrations, such as 107 cells per mL, ensure efficient bioencapsulation without overloading the culture system. The study also highlights that combining several microalgae species can provide a more complete nutritional profile than using a single species, benefiting the growth, survival, and immune function of the larvae.
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Enrichment with soy lecithin
Soy lecithin, a byproduct of soybean processing, has gained popularity as an economical and effective option. Its main advantage is the provision of phospholipids that, when ingested by the artemia, improve the digestion and absorption of other lipids in the larvae’s digestive tract.
Although soy lecithin alone has low levels of DHA and EPA, its combination with other lipid sources results in a synergistic effect that maximizes the assimilation of essential fatty acids. The study confirms that artemia enriched with soy lecithin improves the growth and survival of species like the Pacific white shrimp (Litopenaeus vannamei), in addition to strengthening intestinal structure and stress resistance.
The role of yeasts and probiotics
Beyond lipids, enrichment can also focus on improving the general health and immune response of the larvae. Yeasts, such as Saccharomyces cerevisiae, are an excellent source of protein, B-complex vitamins, and, most importantly, immune-stimulating compounds like ß-glucans. These components strengthen the larvae’s non-specific immune system, making them more resistant to diseases. Additionally, yeasts can improve the pigmentation of the animals, an important factor in ornamental species.
Similarly, enrichment with probiotics (beneficial live microorganisms) aims to introduce healthy bacteria into the larvae’s gut via the artemia. This method, known as bioencapsulation, helps establish a robust gut microbiota that competes with pathogens and enhances nutrient absorption. The study emphasizes that probiotics can increase the activity of digestive enzymes and boost the larvae’s resistance to bacterial infections, which reduces the reliance on antibiotics in aquaculture farms.
Micronutrients: vitamins and minerals
Deficiencies in vitamins and minerals are a common cause of malformations and low survival in larvae. Therefore, enrichment with these micronutrients is an increasingly valued practice. The reviewed study highlights that the biofortification of artemia with vitamin C and vitamin E improves metabolic functions and defense against oxidative stress.
Likewise, supplementation with minerals such as zinc and manganese contributes to better skeletal development and reduces deformities in fish larvae. These interventions not only correct deficiencies but also strengthen the animals’ ability to withstand the challenging conditions of intensive production.
Comparative analysis of fatty acids (EPA and DHA)
The document presents a comparative analysis showing the effectiveness of different sources for transferring EPA and DHA to Artemia. The results are revealing:
- Squid oil and cod liver oil are the most efficient sources for EPA enrichment, with levels exceeding 8% of total fatty acids.
- The microalgae Schizochytrium stands out as the best option for DHA, reaching levels of up to 7.3%.
- Yeasts and non-enriched artemia have minimal EPA and DHA content, underscoring the imperative need for fortification.
This information is crucial for producers to choose the enrichment strategy that best suits the specific nutritional needs of each cultured species, thereby maximizing production results.
Challenges and the future of enrichment
Although much progress has been made, challenges remain. The study notes that more research is needed on which artemia larval stage is most suitable for enrichment and how enriched artemia behaves in response to environmental fluctuations like salinity and temperature. On the other hand, while artemia is an excellent food for larvae, its use in juvenile and adult stages is limited because their nutritional needs change, requiring more complex and varied diets.
In conclusion, the strategic enrichment of artemia is an essential and constantly evolving practice in modern aquaculture. It not only solves a fundamental nutritional problem but also offers a path toward more resilient, healthy, and sustainable production systems, reducing reliance on antibiotics and improving the quality of the final product.
Contact
Yathish Ramena
Great Salt Lake Brine Shrimp Cooperative, Inc.
Ogden, Utah, USA
Department of Aquaculture and Fisheries, University of Arkansas at Pine Bluff
Pine Bluff, Arkansas, USA
Email: ramenay@uapb.edu
Reference (open access)
Ramena, Y., Kurapati, R. B., Bosteels, T., & Ramena, G. (2025). Artemia Enrichment Strategies: A Comprehensive Review of Nutritional Enhancements With Emphasis on Fatty Acid Profiles in Aquatic Species. Reviews in Aquaculture, 17(4), e70080. https://doi.org/10.1111/raq.70080
Editor at the digital magazine AquaHoy. He holds a degree in Aquaculture Biology from the National University of Santa (UNS) and a Master’s degree in Science and Innovation Management from the Polytechnic University of Valencia, with postgraduate diplomas in Business Innovation and Innovation Management. He possesses extensive experience in the aquaculture and fisheries sector, having led the Fisheries Innovation Unit of the National Program for Innovation in Fisheries and Aquaculture (PNIPA). He has served as a senior consultant in technology watch, an innovation project formulator and advisor, and a lecturer at UNS. He is a member of the Peruvian College of Biologists and was recognized by the World Aquaculture Society (WAS) in 2016 for his contribution to aquaculture.
