your fish are spawning…now what? adventures in marine live feeds

Transcription

your fish are spawning…now what? adventures in marine live feeds
YOUR FISH ARE SPAWNING…NOW WHAT?
ADVENTURES IN MARINE LIVE FEEDS
Eric J. Cassiano
University of Florida
Tropical Aquaculture Laboratory
1408 24th Street S.E.
Ruskin, FL 33570
• Demersal Spawners
~4-7 days to hatch
→
Feed that day
• Pelagic Spawners
~1 day to hatch
→
~2-3 days to feed
Clownfish eggs/larvae
http://www.bluevisions.eu
http://www.flickr.com/photos/luko/9283703717/
Diversity of Newly
Hatched Larvae
Ocellaris Clownfish
Striped Blenny
Sergeant major
Bundoon Blenny
Comet
Courtesy Matthew L. Wittenrich
Courtesy Matthew L. Wittenrich
Live Feeds
• Used during the early feeding phase of
most fish larvae (marine and freshwater)
– Higher survival, growth, performance
– Prepared diet not developed for most species
• Used during
broodstock
acclimation
-Micscape Magazine
Live Feeds in Marine Fish Aquaculture
• ‘Traditional’ = wide spread use
– Microalgae
– Rotifers
– Brine shrimp
• ‘Alternative’ = limited use
– Copepods
– Ciliates
– Bivalve larvae
– Barnacle larvae
– Others…
Microalgae
• Numerous species used
– Tahitian strain Isochrysis
galbana (T-ISO)
– Nannochloropsis oculata
– Chaetoceros gracilis
– Pavlova sp.
• Direct / Indirect nutrition
– Active consumption (dinos)
– Passive consumption
– Food for prey
• Shading
Microalgae
• Vessels
• Starters
• Carboys
• Mass
• Cultures
• Batch
• Continuous
Credit: Bay Shellfish Co., manufacturer of the SeaCAPS systems in the Americas
Rotifers
• 2000 species described
• Brachionus sp. (~100 µm BW)
– B. plicatilis (L-strain)
– B. ibericus (S-strain)
– B. rotundiformis (SS-strain)
• Accepted by marine fish larvae
• Ease of culture
– Dense = ~1000/mL
– Algae paste
– Tolerance to water quality issues
– Enrichments
Rotifers
•
•
•
•
Colurella adriatica
Estuarine rotifer (Tampa Bay)
Picture ID (UF)
Culture parameters
–
–
–
−
15 g/L optimal
300 rotifers/mL
Algae paste / bacteria (?)
~45 µm BW
Rotifers
Aquaculture 315:355-360 (2011)
• Proales similis
– 40 µm BW
– Mass cultured
Brine Shrimp
• 7-8 Artemia sp. (?)
• Most widely used live feed
• Produce cysts, timed
hatching
http://agsolution.com/28/artemia-cysts
Brine Shrimp
• Accepted by marine fish
• Large size (450 µm - 12 mm)
• Secondary feed
• Adults used to wean
broodstock
• Microalgae / Enrichments
http://jcoll.org/genoma/vida_microsubmarina/crustaceos/artemia.html
Copepods
• ~27,000 species described
• Dietary component of many
wild marine fish larvae
• Small size (40 µm - 1 mm)
• Appetite stimulatory effect
• Maintenance can be variable
Copepods
• Cyclopoida
– Accept a variety of diets ??
– Nauplii harvest suited for automation
– Variable taxonomic group
• Harpacticoida
– Highest densities
– Epibenthic, wide range H2O quality
– Accept a variety of diets (prepared diet)
• Calanoida
– Well developed production systems
– Egg collection and storage
– Most need live microalgae
Generalized Life Cycle (P. pelagicus)
Nauplii (~90µm)
Copepodite
(~400µm)
Adult with egg sacs (~1mm)
Ciliates
• Strombidium sp.
– Crosshatch Triggerfish
• Fabrea salina
– Red Snapper
• Euplotes sp.
– Golden neon goby
– Pacific blue tang
• Balanion sp.
– Atlantic cod
• Stalked ciliates
• Variable
maintenance
• Used as initial feed
• Quickly grow and
reduce water quality
Other Live Feeds
• Mollusc larvae (clams, oysters)
– Commercially available
– Known diet of some fish
• Barnacle larvae
• Annelid larvae
• Nudibranch larvae
http://www.flickr.com/photos/viucsr/7417983618/
– Bulla striata
• Wild zooplankton
– Sieve and bloom
– Sterilize ?
http://www.microscopy-uk.org.uk
What Now ??
Typical First Feeding Regime
-Main et al., 2007; SRAC 7206
• Florida pompano, developed at Mote Marine Laboratory
• Nannochloropsis sp. (paste or live)
Environment
• Tank size (Larger is better…water quality)
– May vary with species
– Live feed density
• Air flow
– Heavy / light (oxygen levels)
• Water
– Movement
– Shading (live microalgae / paste / clay)
• Lighting
– Photoperiod / wavelength
Feeding
• Feed appropriately
– Low fish larval density ????
• Rotifers
– Multiple feedings of enriched rotifers (4-5x daily)
– System designed to flush excess
• Copepods
– Single daily feedings
– System designed to retain excess
• Artemia (2nd feeding)
– Start slow while co-feeding
– Wean onto pellets as soon as you can
Monitoring
• Water quality…water quality…water quality
• Understand your water source
• Microscope
– Larvae
– Live feeds
– Tank
• Assistance
– Extension agents
– “Specialists” (Rising Tide Conservation)
– Hobbyists forums
Live Feed Resources
• Plankton Culture Manual
Hoff, F.H. and Snell, T.W. (1987)
• Manual on the Production and
Use of Live Food for Aquaculture
Lavens, P., Sorgeloos, P. (1999)
• Live Feeds in Marine Aquaculture
Stottrup, J.G. and McEvoy, L.A. (2003)
• Copepods in Aquaculture
Lee, C-S., O’Bryen, P.J., Marcus, N.H. (2005)
Contact Information:
Eric J. Cassiano
University of Florida
Tropical Aquaculture Laboratory
1408 24th Street S.E.
Ruskin, FL 33570
Phone: (813) 671-5230 ext. 114
Email: ericcass@ufl.edu
Web: http://tal.ifas.ufl.edu/index.htm