1. Flat oyster farming: an opportuny / challenge in mediterranean region
Giuseppe Arcangeli
National Reference Center for fish, mollusc and crustacean diseases
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

2. Main producer countries of Ostrea edulis
FAO
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

3. Bivalves production in EU
Data from: NRLs annual meeting, Saints (Fr) , 2015
Mussel
Cockle
Cupped oyster Flat oyster
(2014)
Mussel
Flat oyster (wild) 62
(2014)
Mussel
Cupped oyster
Flat oyster
(2014)
Mussel
Cockle
Flat oyster
(2014)
Cupped oyster
Flat oyster
(2014)
Cupped Oyster
Mussel
Flat Oyster
Cockle
(2012)
Mussel
Flat oyster
(2014)
Mussel
Clams
Flat oyster
Cupped oyster
(2012)
Mussel
Modiola b
V. Verrucosa 285
Callista
(2014)
Mussel
Cupped oyster
Clams
(2014)
Clam
Cupped oyster
Mussel
(2014)
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

4. A general overview (1)
Ostrea edulis, whose lower (left) valve is convex and upper (right) valve is flat, lives on firm ground in shallow coastal waters down to a depth of 20 m. The oyster, which is a prominent mollusc in the intertidal zone, like other bivalves, can reach other sea areas in its larval stage. The length of the adult oyster is around cm.
O. edulis is is a protandric hermaphrodite.
O. edulis produces up to 1 million eggs per spawning that are liberated into the pallial cavity where they are fertilised by externally released sperm. Following an incubation period of 8-10 days, depending on temperature, larvae (160 μm in size) are released into the environment and spend 8 to 10 days as a pelagic dispersal stage before settlement.
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

5. A general overview (2)
Ostrea edulis has been part of the human diet for many centuries. The Romans built ponds to stock and sort oysters. In the 17th century, oyster spat were collected on rocks, separated from each other and deployed into ponds in salt marshes on the Atlantic coast of France.
delle naiadi.it
Within the past forty years production of Ostrea edulis showed a drastic decline from a peak output of nearly tonnes in 1961, due to the impact of two parasitic epizooites (Bonamia ostreae and Marteilia refringens) in the 1960s (12) and a consequential shift to the rearing of the Portuguese cupped oyster (Crassostrea angulata), then the Pacific cupped oyster (Crassostrea gigas).
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

6. EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015
Renault, 2013
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

7. Benefits A new business:
as the available supply has decreased, average prices have dramatically increased: the wholesale average price for O. edulis is commonly 3 to 5 times greater than the cheaper Pacific cupped oyster (C. gigas). Therefore, the product now occupies a niche market, and is considered as a luxury seafood item, an expensive delicacy for specialized consumers.
An enterprise diversification reduces the business risks
In oyster farming the biotoxin incidence is lower than
in mussels farming
An opportunity to implement the tourism with «typical food»
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

8. Disadvantages/challenges
Lack of farmers with experience
Difficulty in seed recruitment
Short-term trading (full oysters between december-may)
Low production compared to the production of mussels
Competition with the product obtained from fishing on natural beds: prices too low compared to the costs of production in flat oyster culture
Greater investment than mussels
Low motivation of producers
Little awareness of the Administrations .
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

9. Annex IV, part II - Exotic diseases
Directive 2006/88
Annex IV, part II - Exotic diseases
MOLLUSCS
Bonamia exitiosa
Australian mud oyster (Ostrea angasi) and Chilean flat oyster (O. chilensis)
Perkinsus marinus
Pacific oyster (Crassostrea gigas) and Eastern oyster (C. virginica)
Microcytos mackini
Pacific oyster (Crassostrea gigas), Eastern oyster (C. virginica), Olympia flat oyster (Ostrea conchaphila) and European flat oyster (O. edulis)
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

10. Annex IV, part II – not exotic Diseases
Directive 2006/88
Annex IV, part II – not exotic Diseases
MOLLUSCS
Marteilia refringens
Australian mud oyster (Ostrea angasi), Chilean flat oyster (O. chilensis), European flat oyster (O. edulis), Argentinian oyster (O. puelchana), blue mussel (Mytilus edulis) and Mediterranean mussel (M. galloprovincialis)
Bonamia ostreae
Australian mud oyster (Ostrea angasi), Chilean flat oyster (O. chilensis), Olympia flat oyster (O. conchaphila), Asiatic Oyster (O. denselammellosa), European flat oyster (O. edulis), and Argentinian oyster (O. puelchana).
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

11. Notifiable diseases present in Italy
Bonamia ostreae: flat oyster
Marteilia refringens : flat oyster and mussel
...and Bonamia exitiosa : flat oyster (OIE)
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

12. Source: Manual of Diagnostic Tests for Aquatic Animals 2014
BONAMIA EXITIOSA
Bonamia exitiosa is a Haplosporidia protozoan parasite infecting
haemocytes of several oyster species and inducing physiological disorders and eventually death of the animal
no strain identified
Source: Manual of Diagnostic Tests for Aquatic Animals 2014
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

13. B. exitiosa
Life cycle: Transmission of the parasite directly from host to host is possible and transmission by infective stages carried passively on currents between oyster beds is suspected
Susceptible host species: O. chilensis, O. angasi e O. edulis O. stentina
Susceptible stages of the host: In O. edulis, the parasite was detected in market-sized (>60 mm) oysters . There are no data concerning the other oyster stages, including spat. DNA of B. exitiosa has recently been detected in larvae of flat oysters Ostrea edulis.
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

14. Fonte: Manual of Diagnostic Tests for Aquatic Animals 2014
BONAMIA OSTREAE
Bonamia exitiosa is a Haplosporidia protozoan parasite infecting
haemocytes of several oyster species and inducing physiological disorders and eventually death of the animal
no strain identified
Fonte: Manual of Diagnostic Tests for Aquatic Animals 2014
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

15. B. ostreae
Life cycle : The life cycle outside the host is unknown but transmission of the parasite directly from host to host by cohabitation or by inoculation of purified parasites is possible (Hervio et al., 1995), suggesting that no intermediate host is needed.
Susceptible host species: Natural host: European flat oysters, Ostrea edulis. Oyster species infected when moved into B. ostreae endemic zones: Ostrea puelchana, O. angasi, O. chilensis (= Tiostrea chilensis, T. lutaria). However, the parasite was not identified to the species level in these hosts.
Experimental work showed that the following species are not susceptible to B. ostreae: C. gigas, Ruditapes decussatus, R. philippinarum, Mytilus edulis, M. galloprovincialis
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

16. B. ostreae
Susceptible stages of the host: Both 0+ and 1+ year-old O. edulis are susceptible to infection and can develop a high prevalence and high intensity of infection and even mortality over a 6-month period. However, individuals older than 2 years appear to be more susceptible to the disease. Seed from natural settlements appear to be significantly more parasitised than oyster seed from hatcheries. It has recently been shown that larvae can be infected with B. ostreae.
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

17. B. ostreae
hemolymph smear – col. Hemacolor
Connective tissue, hemocytes - col. EE
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

18. Bonamia: epidemiology in UE
B. ostreae
B. exitiosa
B. ostreae/exitiosa
2014
Updated 2013: Ifremer

19. Source: Manual of Diagnostic Tests for Aquatic Animals 2014
MARTEILIA REFRINGENS
Marteilia refringens is a protozoan parasite of the phylum Cercozoa and order Paramyxida infecting the digestive system of several bivalve species and inducing physiological disorders and eventually death of the animal
Marteilia refringens: type O and type M
Source: Manual of Diagnostic Tests for Aquatic Animals 2014
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

20. M. refringens
Life cycle
The life cycle of M. refringens is supposed to be indirect and may include Paracartia grani , at least in pond systems. In other species, including other Acartia spp., the cyclopoida Oithona sp. and an indeterminate harpaticoida species, the parasite has been detected by polymerase chain reaction (PCR) in the natural estuary of the Ebro Delta (Spain), but their role in the life cycle has not been demonstrated.
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

21. B. refringens
Susceptible host species: Oyster species: Ostrea edulis ; and mussel species: Mytilus species including M. edulis and M. galloprovincialis . Infection with M. refringens was demonstrated in the oyster Ostrea stentina, the clam species Solen marginatus and Chamelea gallina and the mussel Xenostrobus securis.
Other Ostrea species including O. chilensis, O. puelchana, O. angasi, and O. denselamellosa were found to be infected with Marteilia sp. when deployed in an infected area . However, in these cases, the parasite identification was not done at the molecular level.
In addition, different stages, including mature stages, of parasites looking like M. refringens, were observed by histology in cockles (Cerastoderma edule), clam species (Ruditapes decussatus R. philippinarum, Tapes rhomboides, T. pullastra, Ensis minor, E. siliqua), and oysters (C.virginica) among other bivalve species. In all these cases, parasite identification is uncertain.
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

22. B. refringens
Susceptible stages of the host: Juveniles and older life stages are known to be susceptible.
Lastly, the copepod Paracartia grani was shown to be susceptible to M. refringens and this species could participate in the transmission of the parasites between bivalves
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

23. M. refringens
Digestive gland (E.E.)
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

24. Marteiliosis: epidemiology in Italy
Prevalence:
< 1%
5-10%
10%
15-20 %
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

25. EMERGING DISEASES: Mikrocytos mackini
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

26. EMERGING DISEASES: pathogenic bacteria
V. splendidus
V. aestuarianus (Sacc. +)
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27. Giardia Criptosporidium
Hazards connected to bivalves consumption
Poisoning
Infections
Biotoxins
Chemical compounds
Bacteria,
Protozoan
Viruses
PSP
DSP
ASP
NSP
Pb, Cd, Hg, Dioxins
PCBs
PAHs
pesticides
Salmonella
Shigella
V. parahaemoliticus
V. Vulnificus
V. cholerae
Giardia Criptosporidium
Toxoplasma
Norovirus
HAV
HEV
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

28. Enteric viruses: an open challenge
A quantitative risk approach must be applied to identify potential problematic oyster harvesting areas
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

29. EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015
………NoV contamination affected classA and class B production areas to a different extent, with a statistically significant difference in both contamination prevalence (22.1% vs. 66.3%)
and quantity (average contamination level of 3.1 × 102 vs. 1.9 × 103 copies/g)......
EU-FIN PROJECT - 2nd Event - Denia (Spain) - 07 May 2015

30. Annual NRL meeting - 16 october 2014 - Rome
ISPRA
MIPAAF
CNR
UNIVERSITA’
ASL
ARPA
ISS MINSAL
IIZZSS
Annual NRL meeting october Rome
10 giugno 2014
Cesenatico
Fattori limitanti la produzione di molluschi