by Zuzanna Mikołajczak PhD, HiProMine SA,Prof. Damian Józefiak, HiProMine SA, Poland
This review examines the implementation of Black Soldier Fly (BSF) larvae in aquaculture feed, focusing on its nutritional, functional, and environmental benefits. The study analyses current research on BSF larvae’s potential as a sustainable protein source and its impact on fish health, growth performance, and environmental sustainability. Particular attention is given to the functional properties of BSF-derived products and their practical application in commercial aquaculture.
The aquaculture sector faces multiple challenges, including increasing environmental pressures and evolving consumer preferences. In this context, insects represent a promising alternative to conventional raw materials used in feed production.
Currently, the most frequently considered substitutes for standard protein and energy components include full-fat meals, partially defatted meals, defatted meals, and oils derived from insect biomass. Insect-derived products are extensively studied in fish nutrition experiments, primarily because they are natural components of many species’ diets (Stenberg et al., 2019). Indeed, most wild fish species consume insects that thrive in aquatic environments (Hodar et al., 2020).
The evolutionary compatibility between fish and insect nutrients opens new avenues for utilising these feed materials in aquaculture diets. Insect-derived ingredients have already been successfully incorporated into the diets of salmonids, including rainbow trout and sea trout, with substantial research focusing on Atlantic salmon.
While the main research stream regarding insect-derived products focuses on growth performance, feed utilisation, and various nutritional and physiological aspects, it is equally important to assess both the practical environmental sustainability of fish farming and the impact on aquafeed quality.
The intensification of research on insect-derived products as innovative feed materials has led to favourable legal regulations regarding processed animal protein, accelerating their implementation in practical aquaculture production. Among the eight species permitted for aquaculture nutrition, the black soldier fly (BSF) has emerged as the undisputed leader, both in terms of research volume and practical applications.
Benefits of BSF Larvae implementation in fish diet
Nutritional profile
The nutritional value of BSF larvae is characterised by its comprehensive chemical composition and functional properties. The crude protein content ranges from 40 percent to 75 percent, depending on the species, while crude fat typically comprises 25 percent to 55 percent of dry matter (Józefiak et al., 2016).
The integration of insect-based feed in aquaculture aligns with fish species’ evolutionary adaptations to their natural diets. This compatibility is evidenced by the presence of chitinase, a specific enzyme in the gastrointestinal tract of certain fish species, which facilitates nutrient assimilation. In Atlantic salmon, for example, chitinase activity has been observed in multiple tissues, including the stomach and intestine, although the precise mechanisms require further investigation (Holen et al., 2022).
Impact on fish health and immunity
The BSF larvae exoskeleton contains chitin, a polysaccharide with significant implications for animal feed. Due to chitin’s chemical characteristics, standard protein conversion factors (N x 6.25) may overestimate protein levels in insect meals; research suggests appropriate factors range between 4.76 and 5.60 (Janssen et al., 2017). Notably, chitin and its derivatives positively influence fish health and immunity when included in diets (Cha et al., 2008; Esteban et al., 2001) and can modulate gastrointestinal tract microbiota (Askarian et al., 2011).
Growth performance enhancement
BSF larvae contain antimicrobial peptides (AMPs), low-molecular-weight cationic proteins that target bacteria, fungi, and certain viruses and parasites through membrane disruption (Józefiak et al., 2016). Research indicates that feed composition during insect growth influences AMP expression (Vogel et al., 2018).
Studies demonstrate that even small quantities of AMPs can improve growth performance and immunological parameters by:
– Enhancing antioxidative capacity
– Increasing stress resistance
– Maintaining intestinal health through microbiota modulation
(Ge et al., 2020; Dai et al., 2020a; Dai et al., 2020b)
Developmental support
Lauric acid, another significant component in BSF larvae, exhibits antimicrobial properties against various pathogens, including Escherichia coli, Clostridium perfringens, and Salmonella spp. (Skrivanova et al., 2007). Feeds high in lauric acid positively affect gastrointestinal histomorphometry (Yazici et al., 2022) and can enhance fish development, antioxidative capability, gut microbiota, and intestinal health (Ullah et al., 2022).
Environmental sustainability
The implementation of BSF larvae in aquafeed offers multiple environmental benefits, particularly significant given the aquaculture sector’s sustainable development challenges, regulatory requirements and customer preferences.
Key sustainability advantages include:
1. Reduced Resource Consumption:
- Minimal space requirements compared to conventional protein sources
- Lower water consumption due to efficient production systems
- Reduced water footprint due to minimal requirements of larvae’s in the growth phase
2. Lower Environmental Impact:
- Decreased methane and carbon dioxide emissions compared to traditional protein production
- Reduced carbon footprint relative to fishmeal production
3. Circular Economy Integration:
- Utilisation of agricultural by-products as feed
Functional properties beyond protein and fat content
BSF larvae-based materials offer numerous functional benefits to fish production, warranting consideration beyond their role as traditional protein and fat sources. The selection of appropriate BSF products significantly influences their functional impact:
Full-fat meal and dried larvae benefits
Full-fat meals provide enhanced functionality compared to defatted or partially defatted alternatives. Ground, dried larvae contain higher crude fat concentrations, resulting in elevated lauric acid levels. This composition allows for reduced proportions of both protein and energy components in feed formulations.
Optimal Implementation
Approaching BSF products as functional ingredients removes the pressure for high inclusion rates.
Research demonstrates that full-fat meal inclusion rates of up to 5 percent yield observable functional benefits without compromising:
- Growth performance
- Feed utilisation
- Nutrient digestibility
(Mikolajczak et al., 2022a; Mikołajczak et al., 2022b; Belghit et al., 2019)
Recent microbiome studies indicate that full-fat meal exhibits more beneficial effects on intestinal microbiome compared to lipid-depleted components (Weththasinghe et al., 2022).
And finally, it is important to remember that we are still dealing with a raw material alternative. The use of an improved nitrogen to protein ratio will be necessary to maintain the properties of the feed. However, for the application of this rule to be effective, the repeatable quality of the component used is necessary – this feature can only be provided by a large-scale insect producer with a stable feeding program. At the same time, such organisations will have no problem delivering the needed volumes.
Commercial implementation and quality assurance
Insect-based nutrients were approved for use in aquaculture nutrition in European Union in 2017. The successful implementation of insect-based nutrients in aquaculture requires: consistent supply chains, repeatable product quality, standardised parameters and large-scale production capabilities
In early stage of their development, companies producing insect-based nutrients were not able to answer sector needs stated above at satisfying level, setting a certain barrier and influenced trust the feed producers put on their suppliers.
Fortunately, the sector is changing, bringing new generation of companies producing insect based components to the market.
One of those is HiProMine, a leading BSF larvae producer located in Poland. HiProMine started operating in 2015 and in 2024 scaled up their innovative solutions, becoming one of the biggest insect-based nutrients producers in Europe.
HiProMine has answered aquaculture feed producers’ requirements through:
- Advanced production technologies
- Rigorous quality control measures
- Scientific research integration
- Sustainable production methods
- Production on commercial scale and short lead times
Moreover, the strategic location of facility in Western Poland, ensures supply chain efficiency.
The HiProMine team is ready to cooperate, share their knowledge based on reliable scientific research and jointly develop solutions that will help develop modern aquaculture.
Promising potential
BSF larvae represent a promising functional ingredient in aquaculture feed, offering benefits beyond basic nutrition. Their implementation supports sustainable aquaculture development while providing numerous advantages for fish health and performance. Future research should focus on optimising inclusion rates and understanding long-term effects on fish populations and environmental impacts.
Published in the November 2024 issue of International Aquafeed.
