Project: BioBullets for Enhanced Sustainable Shellfish Yield

With increasing global population, demand for seafood from aquaculture will be an increasingly important element of food security (1). Global aquaculture of shellfish has seen annual increases of 18% since 1990. Current value of global production for scallops is €2.50bn (10^9) GBP, Pacific oysters €3.0bn, and mussels €1.3m (Appendix 2). While there is increasing global demand for farmed bivalve molluscs, there reCO a number of bottlenecks and limitations which constrain production potential._x000D_First, ‘spat’ has been traditionally collected from the wild. However, supply can be highly variable and unpredictable, with ‘spatfall’ events affected by sea temperatures, flow patterns, predation and El Nino periods (3). Uncertainty of supply presents major production problems for the industry which may endure a year without the arrival of any spat (4). In response, wild collection is being rapidly replaced by hatchery-reared spat, providing a more reliable, higher quality product. However, cultured spat production presents challenges of its own: i) The 'best' diets for spat are the algal species with the richest polyunsaturated fatty acids - PUFAs - requiring large quantities of algae to be cultured, dosed in the optimal proportions and then ingested. ii) Algal cultures are prone to contamination and failure, creating mismatches between supply and demand. iii) Generation of spat requires management of broodstock, with conditioning of adults to reach sexual maturity in high condition. Typically spawning is induced through increasing temperatures, providing food ad libitum and sometimes the use of hormones. However, producing reproductive adults reCOs a major bottleneck in many systems, and is typically limited to seasons when reproduction would occur in the wild (usually July to October). _x000D_Second, key drivers in profitability of commercial shellfisheries are the growth rate and survivorship of larvae to spat/seed (ca. 2mm) within the hatchery, and seed to juveniles (ca. 15mm) within the nursery. For example, in some scallop cultivation situations, survivorship from settled larva to juvenile can be as low as 0.4% (5,App 1)._x000D_The most effective enhancement diets contain algae rich in a select range of PUFAs - docosahexaeonic acid (DHA), eicosapentaenoic acid (EPA) and arachidonic acid (AA). However, even the ‘best’ algal cells contain only minute concentrations of key PUFAs (~2.5pg per 6µm cell), thus requiring large quantities of algae to be cultured, dosed in the optimal proportions and then ingested. Our objective is to develop and test a cost effective method for delivering enhanced PUFA loadings to hatchery-reared shellfish, thus maximising growth rates, minimising time in hatchery and maximising survivorship through improved body condition. In addition, we propose to use enhanced diet supplements to extend the period during which broodstock can be used for propagation._x000D_Our technology lies in the use of a patented, novel and highly effective delivery mechanism: the BioBullet. The innovation lies in encapsulating active ingredients (in this case PUFAs) in edible products which the shellfish filter and ingest. Encapsulation means over 1000 times less product is required than freely dosing the PUFA, with the mussels’ filtering activity concentrating the material from the water. Encapsulation also ensures that optimal formulations can be tailored and delivered to each growth stage and coating materials can be made attractive to maximise uptake. By moving diet supplements away from cultured algae, BioBullets offer a product with a longer shelf life and which overcomes inconsistencies in supply._x000D_BioBullets Ltd. has already successfully developed microencapsules to control invasive zebra mussels (Technology Strategy Board Grant BA225G); the product is being adopted by the UK water industry. This new project presents a range of novel challenges that must be overcome to produce a commercially viable product. Particles must be produced much smaller (4 to 16 µm for seed, 4 to 40 µm for juveniles and broodstock) than previously developed. This requires development of new encapsulation methods. With a smaller size comes the challenge of achieving a high loading of active ingredient. We aim to produce spherical particles (the shape preferred by bivalves) with PUFA content of =20% by mass, a slight negative buoyancy, breakdown time of 30 minutes (so the bullets do not simply pass through the gut), and that is attractive to and filtered by king scallops (Pecten maximus), our test organism._x000D_To ensure rapid commercialisation, the project team includes all elements of the supply chain. Manufacture will be conducted by Micropore Technologies (UK), experts in microencapsulation technologies. Project Management and iterative R&D with the other project Ps will be undertaken by BioBullets (UK), experts in bivalve feeding biology. Scaled-up trials will be conducted at commercial hatcheries and nurseries by Scalpro (Norway)._x000D_

Acronym BESSY (Reference Number: 7995)
Duration 22/04/2013 - 30/09/2016
Project Topic We propose to develop microencapsulated feed products to enhance commercial shellfish yields. Our formulation uses cutting-edge manufacturing techniques to optimise the uptake of the microcapsules by the shellfish.
Network Eurostars
Call Eurostars Cut-Off 9

Project partner

Number Name Role Country
3 Scalpro AS Partner Norway
3 BioBullets Ltd Coordinator United Kingdom
3 Micropore Technologies Ltd Partner United Kingdom