1. Scientific name: Mugil cephalus
2. Common name: Striped mullet
3. Distribution
The mullet distributes throughout the world, mostly inhabiting the trophic and subtrophic areas.
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4. Ecology
The global species has a spawning migration. Larvae are
migrating up to freshwater area where they spend their juvenile life. The fish,
at size 25cm, migrate to coastal waters. The fish feed on small fish, squids,
crustaceans, etc. The fish are growing fast, reaching 25cm in total length in
a year.
5. Aquaculture
Healthy ripe males and females, weighing 1.5¡4.0 Kg for
female and 0.7¡2.5 Kg for female, are selected. Eggs and sperm are obtained
separately by squeezing each gonad of the adult fish, and fertilization is performed
by dry method. The fertilized eggs are contained in the hatching chamber at
density of 100¡200/L. The eggs hatch in 40¡50 hrs. at water temperature
22.2 ¡24.5¡É, salinity 32.5 psu, and illumination 1,000¡2,000 lux.
The larvae are cultured in 20¡30 ton with initial culture
densities 2¡3x103/m3. The culture density decreases
with the culture progress, 4¡5x103/§© at larval size 1¡2cm in body length and 1¡2x103/§© at larval sizes over 3cm
in body length. The just hatched larvae are maintained without water exchange
for 10 days only with gentle aeration. The green water from Chlorella sp. of 500x103cells/mL is preferred. During the larval culture the culture tanks
are illuminated at 2,000¡5,000Lux.
The hatched larvae start to feed from 2 days after hatching. Therefore, rotifers
at density 10¡15/ml should be maintained in the green water. Artificial diet
should be supplied from day 15 after hatching. Under normal culture scheme,
the larvae can reach 41.61mm in body length 50 days after hatching.
The procedure for the seed production of
the mullet in the hatchery
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Mature adult |
Egg squeezing |
Fertilization |
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Fertilized egg after
4-hour |
Embryogenesis after
24-hr |
Embryos before hatching |
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Just hatched lava
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Larval culture tank |
Harvesting seeds
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Transportation of
the seeds |
Transportation |
Seed releasing |
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