CULTURE OF PEARL OYSTER

Presented by :SYED ASSIM HAQRoll No. 2015 ZYM-33M.Sc. Zoology(F)Fishery Science And Aquaculture

INTRODUCTIONPearls are unique as the only gems

produced by a living organism.

These structures are secreted by the mantle (i.e., the skin) of pearl oysters in response to irritations caused by stimuli such as sand grains, molluscs eggs, parasites, detritus, and other foreign particles.

HISTORYKokichi Mikimoto, in 1893 created the

world's first cultured pearl by manually introducing an irritant into an oyster to stimulate it to form a pearl.

Tokishi Nishikawa and Tatsuhei Mise independently learned the secret to spherical pearl production. Their discovery is commonly known as the "Mise-Nishikawa method".

In India, in October 1972, the CMFRI started a pearl culture research project at Tuticorin. Success came in July 1973 when a perfectly spherical pearl was produced.

PEARL OYSTER

TAXONOMYKingdom: Animalia Phylum: Mollusca Class: Bivalvia

Order: Pterioida Family: Pteriidae Genus: Pinctada

Pinctada maxima

Pinctada margaritifera

Pinctada fucata

DISTRIBUTION

•Japan •China•Vietnam•Australia•Indonesia•Myanmar•Philippines•Tahiti

• Shell structure C.L.= conchiolin layer P.L.= prismatic layer N.L.= nacreous layer.

MANTLE AND OYSTER SHELL

Columnar epitheliumConnective tissueCiliated epithelium

• Mantle

Formation of a blister pearl and a free natural pearl inside the mantle

Formation of cultured pearl

PEARL FORMATION

PROTOCOL FOR MARINE PEARL CULTURE

Temperature (20 – 25 °C)

Salinity (above 30 ppt)

Bottom (Gravelly)

Depth (Optimum depth at ~ 15m )

Good phytoplankton production

Moderate water currents

(I) Environmental conditions for culture:

(II) Selection of oysters for operation: • age: above 1.5-2 years• Weight > 25 g (40 mm)• Stage of maturity spent resting stage• Overall health: Good, free from infections (III) Narcotization :• Narcotization of selected oysters by sprinkling

menthol in the sea water.

(IV) Preparation of graft tissue: • 2-3 mm square mantel pieces are prepared.

(V) Implantation: • Single implantation in the gonad near the

intestinal loop.• Double implantation-close to hepato-pancreas.

(VI) Nursing:Implanted oysters are placed in cages.Healing of operated tissue takes about 3-4

days.Dead oysters are removed.Healthy implanted oysters are transferred to

culture cages and suspended at depth of about 2-3 m.

 

• On bottom culture

• Raft culture

Rearing methods

• Long line culture

ECONOMIC IMPORTANCEImportance to cultivators

Sell meat, shells, and mostly pearls.

Importance to businesses provides oysters to restaurant. provides pearls for jewelry business. provides oyster shells which can be used as

ornamentals.

Source of employment

STATUS OF PEARL PRODUCTIONThe world trade of cultured pearl is reported

to be over 3 billion US $ per year. 

India is one of the major importers of pearls importing pearls worth US $ 4 million every year.

 China is the world's largest producer of freshwater pearls, producing more than 1,500 metric tons per year.

• South sea cultured pearls

• Black cultured pearls

• Akoya cultured pearls

REFERANCEwww.fao.org/docrep/field/003/AB726E/

AB726E00.htm#TOCTHE PEARL OYSTER , Paul Southgate and

John Lucas.Wikipediawww.sustainablepearls.org/pearls/global-

pearl-industry/Economic zoology by R.C.SOBTI.

THANK YOU