REPROSEED

REsearch to improve PROduction of SEED of established and emerging bivalve species in European hatcheries

 Partecipanti

Mappa

 Word cloud

Esplora la "nuvola delle parole (Word Cloud) per avere un'idea di massima del progetto.

 Obiettivo del progetto (Objective)

'Secure and stabilised hatchery production of bivalve seed is the unifying objective of the REPROSEED project. Development of innovative new methods will lead to high quality seed of guaranteed physiological health, sanitary status and genetic diversity. By considering the biology of bivalve life stages and the trophic and microbial environment of rearing conditions REPROSEED researches ways of controlling key processes, like reproduction, larval rearing and metamorphosis. New technological advances, like recirculation systems and outdoor algal culture, will provide ways to reduce costs. The need for hatcheries is growing in Europe due to demands from the shellfish industry for quality juveniles and concerns about wild seed due to inconsistent spatfall or environmental harm caused by seed collection of some species. Four economically important molluscs were selected to represent these needs: two species already reared in hatcheries, Crassostrea gigas and Pecten maximus, and two emerging hatchery species, Mytilus edulis and Ruditapes decussatus. Scientific research is most advanced for C. gigas, so its further development will enable us to attain a level of excellence. Knowledge on this species and on P. maximus, an excellent model for solving particular bivalve rearing problems, can also help improve hatchery culture of the other species. Inter-specific differences enable comparative study of important traits. REPROSEED investigates the physiological basis of early sexual maturation, gamete competency, immunity and metamorphosis, at cellular and molecular levels, including genomics and proteomics. Application of these results and dedicated studies will be made on practical aspects of controlled bivalve reproduction, nutritional needs for broodstock conditioning and larval growth (including testing of mutant yeasts and lipid microcapsules) and the benefits of probiotics. Advances will be shared with end-users throughout the project.'

Introduzione (Teaser)

EU scientists have explored new ways to improve the production of bivalve seed: European clam, Pacific oyster, great scallop and blue mussels.

Descrizione progetto (Article)

Shellfish production in Europe is subject to environmental changes, notably affecting the availability of natural spatfall and favouring the emergence of disease outbreaks. Hatcheries offer ways to counter these threats through their potential to ensure a more stable supply of seed and to carry out selective breeding to improve disease resistance.

To achieve these objectives, the methods of rearing may be improved to make them more reliable, to decrease the seed production cost and to guarantee its quality. To address these issues, the EU funded research into commercial bivalve species through the http://www.reproseed.eu/ (REPROSEED) project.

REPROSEED focused on broodstock management, gametes, larvae and seed quality, and improved rearing methods.

Mass sequencing of gene transcripts was performed at successive stages of development of the studied species, providing new data and genomic tools. They are used to identify the genes involved in the acquisition of competence, maturation, the immune response to stress or pathogenic bacteria. Their analysis led to better understanding of the development phases and the ontology of immune system. Another aspect of the project identified protein markers that estimate the quality of eggs and sperm.

The use of RAS (Recycling Aquaculture Systems) to rear larvae and postlarvae gave very positive results, which encourage the replacement of traditional batch or flow-through systems with specific adaptation for each species. RAS significantly reduce needs for water, energy and labour, and provide a more stable environment.

Probiotics provided to scallop larvae increased their survival, settlement and the resulting seed yield. They are a promising new development for rearing such sensitive larvae. Microbiota of larvae and postlarvae is specific and complex and may influence bivalve development as demonstrated by the effect of probiotics. To prevent the contamination by pathogenic bacteria it is necessary to apply strict sanitary rules but also to maintain diversity of bacteria in rearing.

REPROSEED developed tools to estimate genetic diversity in bivalve seed. Genetic diversity of hatchery seed is an important issue into bivalve farming due to high variance in individual reproductive success, notably in restocking or selective breeding programs.

The relationship with mollusc hatcheries in Europe established during the project through a survey of this sector and a workshop with producers has created a dynamics to better collaborate and to build future collaborative projects between research and industry.