3. Overview
Most popular species in the reef food fish industry in Asia-
Pacific region
Fast growing, hardy ,suitable for intensive culture
Excellent characteristics for processing due to unique culinary
attributes and scarcity
In 1997, the Asia-Pacific Region contributed about 90% to the
world Aquaculture prdxn w/ Grouper at 15000 ton w/ China as
the biggest producer contributing 8000 tons followed closely
by Indonesia. Other countries in the region commonly
produces 1000-2000tons annually in 1990-1997.
Although grouper culture is widespread in Asia and Pacific, its
continued dvlp. is constrained by the limited availability of
fingerlings. Most economies w/recent exception of Chinese
Taipei, rely almost totally on wild-caught fry and fingerlings for
stocking.
4. The word "grouper" comes from the word for the
fish, most widely believed to be from the
Portuguese name, garoupa. The origin of this name
in Portuguese is believed to be from an indigenous
South American language.
In Australia, the name "groper" is used instead of
"grouper" for several species, such as the
Queensland grouper (Epinephelus lanceolatus).
In the Philippines, it is named lapu-lapu in Luzon,
while in the Visayas and Mindanao it goes by the
name pugapo.
In New Zealand, "groper" refers to a type of
wreckfish, Polyprion oxygeneios, which goes by the
Māori name hāpuku.
In the Middle East, the fish is known as hammour,
and is widely eaten, especially in the Persian Gulf
region.
5. Groupers are teleosts, typically having a stout body
and a large mouth. They are not built for long-
distance, fast swimming. They can be quite large,
and lengths over a meter and weights up to 100 kg
They habitually eat fish, octopuses, and
crustaceans. Some species prefer to ambush their
prey, while other species are active predators.
Their mouths and gills form a powerful sucking
system that sucks their prey in from a distance.
They also use their mouths to dig into sand to form
their shelters under big rocks, jetting it out through
their gills. Their gill muscles are so powerful, it is
nearly impossible to pull them out of a cave if they
feel attacked and extend those muscles to lock
themselves in.
6. LIFE CYCLE
Many species move to particular areas at the same time each
year to reproduce in spawning aggregations. In these
aggregations, females release eggs (some larger individuals
produce over 1 million eggs) and these are fertilized by sperm
released by males. The fertilized eggs hatch to very small forms
(larval stages) which drift in ocean currents for 1 to 2 months.
Less than one in every thousand of the small floating forms
survives to settle as a juvenile in shallow water near reefs. As they
grow, they move onto coral reefs and less than one in every
hundred of the young
fish (juveniles) survives to become an adult.
9. Groupers are mostly Protogynous Hermaphrodites,
they mature only as females and have the ability to
change sex after sexual maturity
Some species of groupers grow about a kilogram
per year and are generally adolescent until they
reach three kilograms, when they become female.
The largest males often control harems containing
three to 15 females.
Groupers often pair spawn, which enables large
males to competitively exclude smaller males from
reproducing.
However, some groupers are gonochoristic.
10. Gonochorism, or a reproductive strategy with two
distinct sexes, has evolved independently in
groupers at least five times. The evolution of
gonochorism is linked to group spawning high
amounts of habitat cover.
Both group spawning and habitat cover increase
the likelihood of a smaller male to reproduce in the
presence of large males.
Gonochoristic groupers have larger testes than
protogynous groupers (10% of body mass
compared to 1% of body mass), indicating the
evolution of gonochorism increased male grouper
fitness in environments where large males were
unable to competitively exclude small males from
reproducing
12. CAUSES
Removal of males from the population leads to sex
change in the dominant(largest) females.
The sex ratio would depend upon the current
spawning sex ratio within the aggregation, the
proportion of adults surviving to spawn in
subsequent years, and the proportion of
inshore juveniles surviving to mature and enter
successive aggregations.
13. Some grouper population, males are more
or less absent ‘till age 10
In case of Red grouper( Epinephalus
morio), the sex ratio is not equal until age
15.
Some Grouper can live 20 years or more!
14. Fishing
Huntsman and Schaaf (1994) point out that both
protogynous and gonochoristic (separate sexes)
population tends to lose reproductive capacity as
fishing pressure increases.
In protogynous stocks, however, increased fishing
mortality might reduce the relative abudance of
males by reducing the abundance of older-classes
and diminish the probability that eggs will be
successfully fertilized
15. Loss of behavioural interactions between male and
female
Combined with continued interaction between
females, (Koenig et al. 1999) suggested that the
loss of male-female interaction in Gag grouper
(Mycteroperca microlepis) occur at the endof
aggregation period, when females purportedly
return to swallower inshore waters.
16. To date:
Only specie of grouper investigated
Red hind(Epinephalus guttatus) and coney (Epinephalus
fulva) have been histologically proven to be protogynous
hermaphrodites but;
Collin(1992) groupers that aggregate are not necessarily
protogynous.
Ex: Nassau grouper(Epinephalus stiatus) and
Yellowfin grouper( Mycteroperca venenosa),
neither of them shown to be protogynous but
both known to aggregiate.
17. Nassau grouper (Epinephalus stiatus) spawns in
very large aggregations( thousands to ten
thousands of fish) for only a few weeks of the year.
In contrast, male and female Gag grouper
(Mycteroperca microlepis) and Red hind
(Epinephalus guttatus) co-occur only during
spawning season.
18. ARE GROUPERS AVAILABLE ANY TIME OF THE
YEAR?
COLLECTION AREA MONTH GROUPER SIZE
Peninsula Malaysia, east
cost
November to December Average 2cm
Indonesia(e.g., Banten
Bay)
February to April Fry
Thailand, coastal waters
near mangrove areas
January to March 7.5-10 cm fingerlings
Philippines, variable peak
season in diff. Province
Peaks mostly in June to
December or October to
November and April to
May
Tinies, fry and fingerlings
24. HATCHERY DESIGN
Key
component:
Regardless
of scale is
the
implementat
ion of
biosecurity
to reduce
the
incidence of
disease,
(VNN)viral
nervous
necrosis.
ENTRANCE OF HATCHERY FACILITY
25. VNN (VIRAL NERVOUS NECROSIS)
A common disease problem in marine finfish
hatcheries affecting most cultured marine finfish
species, including grouper .
Caused by a nodavirus also known as viral
encephalopathy and retinopathy.
Symptoms are disorientation of fish ,change in
color, becoming more dark.
Can be reduced by strict biosecurity. .
26. KEY FEATURES FOR BIOSECURITY
Separation of various functional areas;
Access to hatchery limited only to essential
personnel;
Disinfection and thorough cleaning of all
equipments;
Routine monitoring for pathogens and
disease;
Optimisation of water quality and nutrition
to improve overall health and resistance of
larvae.
28. BROODSTOCK ACQUISITION
1. Collecting and purchasing of wild fish in a wide
range of sizes.(Epinephelinae, protogynous
hermaphrodites).
In Philippines size of mature female(2.2 kg),and male
(3.5 kg).
2. Grow fish produced in the hatchery (in cage,
pond, or tanks) however, takes 4years to grow
juvenile Tiger Grouper up to broodstock size .
29. CRITERIA FOR BROODSTOCK SELECTION
Normal body shape and colour
Absence of skeletal deformities
Overall healthy status i.e., absence of large wounds
haemorrhages, infections, and parasites
Normal behavior, i.e., good response to food
distribution
Best growth and food conversion rate within this
age group.
30. TRANSPORT REQUIREMENTS FOR BROODFISH
Transported in dark-coloured, covered tanks
containing aerated or oxygenated water, to reduce
stress.
Dissolved maintained at >75% saturation at all
times.
Mild sedation(using approved sedatives for fish) to
reduce stress and for easier and safer handling.
Fish should not be fed at least 24 hours before
hand to prevent faeces and regurgitated feed from
fouling transport water.
31. TREATMENT BEFORE STOCKING
Quarantine the fish
To reduce the opportunity for new fish to transmit parasites or
diseases to the established fish. Quarantine process-takes
between 1and 4 weeks in small tanks(0.5-2 cubic meter)to
facilitate water exchange and fish handling.
This period focuses on reducing parasite load of fish regularly
by placing them in freshwater bath for 5 min. to eliminate
common parasites (skin flukes, protozoans etc.)
If water quality in broodstock tanks markedly different form
previous holding environment, fish acclimation by placing
them in a tank filled with original water, and slowly add new
tank water for up to 1 hr. before releasing them into the tank.
32. BROODSTOCK TANKS
Tank size. When fish is(>10kg.) size ranges bet.50-100cubic meters.
Preferred tank color. Medium-range blue, brown or grey not very light or dark-shades.
Depth. 2m preferably >2.5 to allow sufficient room for spawning behavior.
Broodstock tanks are roofed in order to reduce the growth of algae on tank walls
making egg collection difficult and increasing egg parasite infestation.
Dirty tanks must be cleaned frequently w/c may stress broodstock and cause
spawning failure or lower quality spawned eggs.
Continously supplied with fresh seawater at daily exchange rate of 200-300%.
Seawater should be filtered and clear with stable salinity (33-35ppt) and water
temperature (27-30.5 degrees celsius).
Tanks located outside are subject to the natural photoperiod, while indoor may be
provided with artificial lightning to simulate different photoperiod regimes.
33. TANK CLEANING
Siphoning of excessive feed that accumulate on
bottom to prevent water quality degradation.
After spawning remove excess dead eggs w/c
decay and pollute the water .
Broodstock should be bathed in freshwater for 5-7
min. During tank cleaning to reduce incidence of
parasite infestation.
34. BROODSTOCK MANAGEMENT
Feeding
feed to satiation (6x a week),w/fish (4x a week) ,w/ squid(2x a
week)
Feeding may vary, depending on availability of fish and
squid.{herrings and mackerels are commonly used as feed}
Feed is supplemented with a vitamin mix included at 1% of feed.
Commercial or custom-formulated vitamin mixes can be used.
35. COMPONENTS OF FEED MIX
Ingredients Amount
Minced fish, squid, shrimp, etc. 793g
Rice flour or other finely ground
starch product
195g
Transglutaminase B 10g
Vitamin mix 1-2g(depending on recommended
inclusion rate)
Total 1kg
38. NATURAL SPAWNING
o Occurs at night 9pm-3am for 3-6 nights
each month during the new moon phase.
However, studies shown that they spawn
throughout the year.
o 0.8-6.0 M eggs each night.
o cease to spawn when temperature drops
around 25 degrees celsius.
39. IMPORTANT ENVIRONMENTAL PARAMETERS
ph 7.5-8.3
temperature 25-32 degrees celsius
salinity 20-32 ppt
Dissolved oxygen 4-8 ppm
NO2-N(Nitrogen Nitrite) 0-0.05 ppm
Unionized ammonia < 0.02 ppm
Australian Center for
International Agricultural
Research ,2012
40. INDUCED SPAWNING
Prior to Induction: after acquisition of broodfish is
stocked at concrete tanks at 6-12 months;
Stocking density:1/2 cubic meters;
Feed: fed daily with fresh trashfish;
Feeding rate: 5% body weight;
Tank water:50-70% is changed daily.
And condition simulating the natural
environment.
41. INDUCED SPAWNING CONTINUE…
o Species selected for induction:
female-having mean egg diameter of 400ug.
male- with running milt.
o Ratio: female to male is 10:4
o Weight range: female(3.6-6.5 kg),male(10-16 kg).
o Hormones used: Human Chorionic
Gonadotropin(HCG), Pituitary
Gland(PG),Luteinizing Releasing Hormone –a
(LRH-a).
o Hormone administration type: Multiple dosages.
42. INDUCTION PROCEDURE
First injection, at dosages of 500 IU HCG + 3mg of
PG per kg of fish, and at final injection at 1000 IU
HCG + 3mg of PG per kg of fish at an interval of 24
hours, results showed that treated fish spawned
naturally in spawning tank 12 hours after final
injection.
o However, at lower dosages of 500 IU HCG + 3mg
of PG at 24-hour intervals or using 10 mg LRH-a at
12-hour intervals, eggs can be artificially fertilized.
In cases where ovulation did not occur after the
second injection,a third injection was given.
43. FERTILIZATION
After injection the fertilized egg that
naturally spawned in tanks were
collected with a fine dip net(100
micron mesh size). Planktonic
organisms and detritus were removed
by screening, unfertilized eggs settled
down on bottom of tanks were
removed by siphoning.
45. TABLE 1.TYPE OF HORMONES, DOSAGES AND TIME
INTERVALS USED FOR INDUCED SPAWNING
Treatment Hormones used Dosage Time interval(hr)
A HCG + pituitary
gland of Chinese
carp
500 IU + 3 mg
PG / kg
12
B HCG + pituitary
gland of Chinese
carp
500 IU + 3 mg
PG / kg
24
C LRH-a 10ug/kg 12
D HCG + pituitary
gland of Chinese
carp
(1st) 500 IU +
3mg /kg
(2nd) 1000 IU +
3mg PG/kg
24
50. C 8 4.1 12 3 Partial
ovulation,15
hr after final
injection.
Fertilization
rate 40%;
hatching rate
50%; larvae
healthy.
9 4.5 12 3 LRH-a
10u/kg of
fish
Ovulation 12
hr after final
injection.
Fertilization
rate 80%;
hatching rate
40%;larvae
healthy.
51. 10 5.2 24 2 1st
injection-
HCG 500
IU + 3mg
/kg of fish .
2nd
injection –
HCG 1000
IU + 3mg
PG/kg of
fish.
All fish
spawned
naturally
12 hr after
final
injection.
Fertilizatio
n rate
30%;
hatching
rate 70%,
larvae very
healthy.
D 11 5.5 24 2
12 6.6 24 2
52. RESULTS FOR INDUCED SPAWNING
The fish under treatment D (Table 1),spawned
naturally in tank 12 hours after the final
injection(Table 2). Fish under treatment B (Table1)
ovulated 12-15 hours after the final injection, but
fertilization was completed only by artificial
stripping.
Fish in treatments A and C required a third injection
for ovulation, eggs were artificially fertilized 9-15
hours after the final injection.
Ovulation rate of the females treated with hormonal
injections at 24-hour intervals was higher than
those at 12-hour intervals(Table 2),this is due to
handling that cause fish stress.
53. LARVAL AND FRY REARING
(Epinephelus salmoides)
The larvae from hatching containers were collected and
stocked in nine 250-1 fiberglass larval rearing tanks at a
stocking rate of 2500 larvae per tank.
3 types of feed were tested in 3 replicates on a
completely randomized design.
o Type of feed fed to fry:
1st type- sea urchin eggs and Isochrysis;
2nd type-Isochrysis and Brachionus;
3rd type- Tetraselmis and Brachionus
The larvae were reared indoor under intensive care
conditions.
Beginning on day 3 feed was introduced.
20-30% of water was changed daily.
54. RESULTS FOR LARVAL AND FRY REARING
sea urchin eggs are suitable feed for grouper
larvae, diameter of sea urchin egg was about 50ug.
Survival rate of fry fed with:
• sea urchin eggs and Isochrysis from hatching to 20
days old was 9%;
• 2% for those fed with Isochrysis and Brachionus;
• none of the fry fed with Tetraselmis and Brachionus
survived; all the larvae died after a culture period of
6 days.
55. FINGERLING PRODUCTION
At 45 DAH-larvae have metamorphosed into
juveniles ranging from 2.0-2.8cm.
5-40%-survival rates at 45 DAH.
15-25%-survival rates at density of 10larvae/L.
20,000 fingerlings-expected harvest at density of 10
larvae/L, at 10 cubic meter tank.
batch basis –in hatchery mgt. that is each batch of
larvae is treated as separate production cycle, and
hatchery is shut down between each production
cycle.
58. COLLECTION
Fertilized eggs are collected from the overflow of
egg collector tank using fine net.
Removal from collection net once the embryo has
developed optic vesicles.(i.e., at the eyed stage.
However, handling eggs before this stage increases
mortality and deformity.
59. DISINFECTION
Treated with ozone to minimize the chances of
vertical transmission of VNN (Viral Nervous
Nacrosis) from parent to offspring.
Ozone at concentration of 1 mg/L for 1 min.
Equivalent 0.8mg/L for 1.25 minutes.
Precautionary measure should be taken when
treating Ozone.
60. INCUBATION
After treatment, eggs are rinsed with clean and
disinfected seawater.
Eggs are transferred into 0.5-1.0 cubic meters with
aerated seawater.
61. LARVAL REARING PRACTICES AND
REQUIREMENTS
Larval Tanks-volume of 10cubic meter, depth of 1.2m,
color of bright yellow or pale blue to allow grouper larvae
to discriminate prey more easily and tank cleaning
easier, roofed, and enclosed to maintain water temp.,
and facilitate biosecurity. Quarantined area with entry
and exit of authorized person only, disinfection of all
equipments.
Aeration-provided in a grid pattern to ensure even water
mixture, maintained DO levels, placed in corner to
prevent stagnation, should be in the light in the early
stage to prevent physical damage and could be
increased if the larvae become robust.
Water-should be filtered [filtered through ultraviolet or
ozone disinfection],help maintain biosecurity.
62. LARVAL REARING PRACTICES AND
REQUIREMENTS
Sea water used must be per-treated using sand
filter to remove particulates, and then sterilized to
reduce potential pathogen intro.
in water.
10 larvae/L-recommended initial stocking density
for grouper.
Oil-added to form thin film on water surface(around
0.2/m L-meter square)at 1-5 DAH to prevent
surface aggregation mortality in early stage.
63. PROBLEMS IN LARVAL REARING
Surface aggregation mortality.
Larvae are attracted to patches of sunlight in the
tank hence, where that patch is present they may
swim to surface of tank. Results in becoming stock
in water and entangled in each other spines.
Larval mortality at first feeding.
64. LIVE FOODS
NUTRITIONAL ENHANCEMENT
Larvae of grouper require high levels of highly
unsaturated fatty acids, EPA, ARA, DHA. Provision
via incorporation in live foods.
Recommended for larvae:
Artemia
Brachionus
Isochrysis
Tetraselmis
66. PHILIPPINES
Grouper aquaculture in the Philippines is based on
the grow-out of wild-caught fry and fingerlings.
Grouper fry and fingerlings are caught using a
variety of methods including hook and line, scoop
or dip nets, traps, gango or fish nest, fish corral, and
several types of nets. In the Philippines, the major
sources of grouper fry include the provinces of
Pangasinan, Cavite, Mindoro, Quezon, Masbate,
Bulacan, Cagayan, Dadiangas, Zamboanga del Sur
and Negros Oriental. The Philippines is one of the
largest suppliers of wild-caught grouper fry, fingerlings
and juveniles in Southeast Asia.
67. REFERENCES
Australian Center for International
Agricultural Research
SEAFDEC,AQD Iloilo, Philippines
Full- Cycle Aquaculture Status and Trends
