IMPROVEMENT OF LARVAL REARING TECHNIQUE FOR Cromileptes altivelis

Gondol Research Institute for Maricultture Central Research Institute for Aquaculture

Australian Centre for International Agricultural Research(ACIAR)

Improved Hatchery and Grow-out Technology for Grouper Aquaculture in Asia-Pacific Region

Introduction

Improve technology

• Natural seed declining• Survival rate is irregular • High demand (as ornamental & Aq.)• High value (US$:12-78/kg)• Promising for business

Improvement of LavicultureTechnology

Aiming to:• Improve survival rate

• Improve quality of seeds

• Standardize the procedure of larviculture

• Broodstock management• Eggs selection• Larval feeds• Larval rearing • Diseases• Further development

Scope of research

BROODSTOCK MANAGEMENT

Maturation -Outdoor circular tank, 100-t, 2-2.5 m deep-Flow through system, exchange rate 200-400 % -Sex ratio M:F (1:2). Female(1-2.5 kg BW), Male(>2.5 kg BW)-Feed fresh mixed trash fish+squid+1% Vit.mix (1-3 % BW/day)

Spawning:Throughout a year, 3-7 before & after new moon phase

Caution

• Use only floating eggs• Wash eggs with 20 ppm iodine or UV treated water• At water temperature 27-28 oC, eggs hatching 18-20 hrs.• Density eggs for laviculture 5-10 eggs/l

Egg Selection

Larval feed:

-Nannochloropsis-Enriched rotifer -Enriched Artemia-Artificial diet (commercial larval feed)

05

101520253035

Body length (µm)

Freq

uenc

y

90 110100 120 130 140 150 160 170 180

Larval rearing•Tank shape: circular or rectangular • Vol. 10-t, 1.2 m deep• Light blue, yellow color• Roofed or indoor hatchery

Larval Rearing (Cont.)

Days after hatching 0 5 10 15 20 25 30 35 40 45 50------------------------------------------------------------------------------------------Feeding regime: Nannochrolopsis --------------------- SS-rotifer (5-7 ind/ml) --- S-rotifer (8-10 ind/ml) ----------------- Artemia (0.2-0.5 ind/ml) ------------------------------ Artificial diet

ML-200-400 -------------------------ML-400-800 -------------------

Water management: Squid oil ---- Water exchange 10% -----------

20% -------------50% --------

Running water -----------------Siphoning -----------------------------------------------

Feeding & water management schemes

Survival rates• At Research Institute: 23.4-54.9 %• At Commercial Hatcheries (4): 11.3-51.0 %• At Backyard Hatchery (10) : 7.0-35.4 %

Factor contributing larval mortality•Egg quality•Floating death, trapped water surface•Elongated dorsal spine•Nutritional deficiency•Virus VNN

Further development

• Two Government hatcheries• Four commercial hatcheries• More than hundred backyard hatcheriesbeing actively produce the seed.

Aceh

Batam

LampungJepara

Lomok

TakalarAmbon

GondolMaros

Development centre for maricultureResearch Institute for marine and brackish water culture

Thank you for your attention