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LIVE FEED. AKU3201 Principles of Aquaculture. Life cycle. Broodstock –> larvae -> fry -> fingerling -> juvenile. Larvae. Very small Extremely fragile Physiologically not fully developed Small mouth Still developing organ (i.e., eyes, chemoreceptors, digestive system).
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LIVE FEED AKU3201 Principles of Aquaculture
Life cycle • Broodstock –> larvae -> fry -> fingerling -> juvenile
Larvae • Very small • Extremely fragile • Physiologically not fully developed • Small mouth • Still developing organ (i.e., eyes, chemoreceptors, digestive system)
Natural/Live food • Phytoplankton/ Microalgae • Zooplankton • Invertebrate • Nematode
Phytoplankton • Microalgae • 2-20 mikrometer
Nutritional value • High unsaturated fatty acids (HUFA) • Eicosapentaenoic acid (EPA; 20:5n-3) • Arachidonic acid (ARA; 20:4n-6) • Docosahexaenoic acid (DHA; 22:6n-3)
Microalgae Food for: • Bivalves • Penaeid shrimp • Fish • Rotifer, Artemia
Problem: • Crash of algal culture Solution:
Zooplankton • Rotifer • 50 – 200 mikrometer
Rotifer • Brachionus plicatilis • Euryhaline: able to tolerate wide range of salinities • Suitable for crustaceans & fish
L- type = 119-241 mikron S- type = 93 – 179 mikron SS- type = 90 – 159 mikron
Advantages • Small size & slow swimming velocity • Suitable for fish that can’t ingest Artemia nauplii • Possible to rear at high density • Suitable for bioencapsulation/ enrichment
Brine shrimp (Artemia) • 400m- 800 mikrometer
NAUPLII ADULT
Artemia • Nauplii of Artemia mostwidely used food item
Able to tolerate > 70 ppt & up to 250 ppt. Why? • Able to produce dormant eggs (cyst) = Diapause
Available in cysts • Advantages? • Place cyst in well-aerated seawater => hatch into nauplii after 24 hours • Nauplii positive phototaxis
Problems with live food • Problems in obtaining steady supply of adequate quantities at appropriate times • Hard to ensure the quality & quantity of natural food • Nutritive value vary according to culture conditions • Contamination