comparative study of the reproductive performance of four strains of artemia
DESCRIPTION
Comparative Study of the Reproductive Performance of Four Strains of Artemia. Eythan Moren u , Alexandra M é ndez, Robert J. Mayer, and Liza V. Jim é nez. University of Puerto Rico at Aguadilla Department of Natural Sciences. March 1, 2007. - PowerPoint PPT PresentationTRANSCRIPT
Comparative Study of the ReproductivePerformance of Four Strains of Artemia
Eythan Morenu, Alexandra Méndez, Robert J. Mayer, and Liza V. Jiménez
University of Puerto Rico at AguadillaDepartment of Natural Sciences
March 1, 2007
This presentation evaluates important aspects of the ecological physiology of the genus Artemia inPuerto Rico
Discussion of research data and conclusions
Background on the genus Artemia
Preliminary work – Effects of Neem on Artemia
Artemia are Anostracan Branchiopods that are well adapted to the extreme conditions of hypersaline environments
Synthesis ofhemoglobins
Heat tolerance
Flexibility in diet
Production of resistant stages
Efficient osmoregulation
oviparous
ovoviviparous
Life cycle of Artemia is tightly coupled tothe environment
Continuous reproduction
Alternation of reproductive mode
There are sexual and parthenogeneticspecies
Artemia is a very important organism from an ecological and economic perspective:
Artemia biomass is used inaquaculture (fish food)
Artemia are important for the production of salt and for thesurvival of many species of birds in salt flat systems
What is the importance of locating and characterizing populations of Artemia?
Main question
• Are there significant differences in the reproductive performance of various populations of Artemia when reared under constant conditions?
Ventilationchamber
Nylon mesh (100 m)
Water level
Isolation chamber
Plankton isolation chambers were used toisolate reproductive couples
Animals grown in mass culture until sexual maturity
Introduced in isolation chamberupon reaching sexual maturity
A plankton recirculation apparatus was used in the life history experiments
Control chamberExperimental chamber
Pump Pump
Water intake(100 m mesh)
Water intake(100 m mesh)
Isolation chambers
Isolation chambers
Water distribution pipe Water distribution pipe
Rigid plastic tubing Rigid plastic tubingClear plastic partitions
Spigot Spigot
Heater Heater
TOP VIEW
23° C
Salinity of 45
Populations
APAR LPPR CRPR GSL
Nu
mb
er o
f o
ffsp
rin
g p
rod
uce
d p
er c
oh
ort
0
400
800
1200
1600
2000
Number of nauplii
Number of cysts
Life history experiments showed that the totalnumber of offspring produced was higherfor APAR
The production of nauplii was lower than that of cysts
Production of mixed broods
Random alternationbetween reproductivemodes
Populations
APAR LPPR CRPR GSL
Lif
esp
an
(d
ays
)
0
40
80
120
160
Max = 106
Min = 72
Max = 120
Min = 72
Max = 79
Min = 36
Max = 219
Min = 75
The lifespan of APAR individuals was higherthan that of the other populations
Higher reproductivepotential for APAR
Time Units (10 days)
1 2 3 4 5 6 7 8
0
200
400
600
800
1000
GSL
Time units (10 days)
0 1 2 3 4 5 6 7 8
Nu
mb
er o
f o
ffsp
rin
g p
rod
uce
d p
er c
oh
ort
0
200
400
600
800
1000
nauplii cysts
APAR
There was a significant time - dependent reduction in reproductive potential forall populations
Conclusions
The reproductive performance of Artemia
varies between strains and is affected by
environmental conditions
A. parthenogenetica had the highest
reproductive performance of all the
population tested
This tree is originally from India.
Its many properties can be used to cure many diseases and in the creation of insecticides.
Preliminary work with neem seed extracts and Artemia suggests that this extract could increase the growth rate of these animals.
Quick facts about Neem (Azaridachta indica)
We want to know if neem seed extracts have a significant effect on the survival, growth and development of Artemia.
This research can have important aquacultural applications.
Results can shed light on the culture of other
economically important crustaceans
Future direction of the research – Neem
Neem Experiment -
Research question:How will a series of concentrations of neem seed extract affect the survival of Artemia larvae?
After 24 hours of the experimental test tubes were observed and the live and/or dead Artemia nauplii were counted.
An acute toxicity assay was performed
Concentration (g/l)
0 10 20 30 40 50
Per
cent
of L
ive
Ani
mal
s
65
70
75
80
85
90
95
100
Significant mortality at concentrations above 25 g/l
• If neem seed extract would promote a faster growth rate it could be used to accelerate development of Artemia satisfying the growing demand of Artemia in the aquaculture industry.
Future direction of the research – Neem
The reproductive performance of Artemia
varies between strains and is affected by
environmental conditions
A. parthenogenetica had the highest
reproductive performance of all the
populations tested
Reproductive Performance Experimen Neem Experiment
At concentrations of 1g/l – 25g/l Artemia nauplii had high survival
We will continue experiments to determine the effects of Neem on
development and growth of Artemia.
Acknowledgements
R. B. Forward and D. RittschofDuke University Marine Laboratory
UPR Sea Grant College Program Award Number NA16RG2278
University of Puerto Rico at Aguadilla
US Fish and Wildlife Service – Caribbean Islands NWR
Artemia Reference Center – Gent, Belgium
PR-LSAMP
The reproductive performance of Artemia
varies between strains and is affected by
environmental conditions
A. parthenogenetica had the highest
reproductive performance of all the
population tested
Reproductive Performance Experiment - Results
Neem Experiment - Importance
At concentrations of 1g/l – 25g/l Artemia organisms survived.
We will continue experiments to determine the effects of Neem on Artemia at these concentrations.
Questions?