comparing different supplemental foods for artemia in the intensive culture system

CAN THO UNIVERSITY
COLLEGE OF AQUACULTURE AND FISHERIES

COMPARING DIFFERENT SUPPLEMENTAL FOODS FOR
ARTEMIA IN THE INTENSIVE CULTURE SYSTEM

By

BUI THANH DIEU

A thesis submitted in partial fulfillment of the requirements for
the degree of Bachelor of science in Aquaculture

Can Tho City, January, 18th 2013


CAN THO UNIVERSITY
COLLEGE OF AQUACULTURE AND FISHERIES

COMPARING DIFFERENT SUPPLEMENTAL FOODS FOR
ARTEMIA IN THE INTENSIVE CULTURE SYSTEM

By

BUI THANH DIEU

A thesis submitted in partial fulfillment of the requirements for
the degree of Bachelor of science in Aquaculture

Supervisor
Assoc.Prof. NGUYEN VAN HOA

Msc. TRAN HUU LE
Can Tho City, January, 18th 2013


ACKNOWLEDGEMENT
I would like to thank the head of the Department of Aquaculture and Fisheries of
Can Tho University has created favorable conditions for learning, studying and
teachers imparted to me knowledge that will become the foundation for my future.
I wish to express my deep appreciation and sincere gratitude to my advisor Dr.
Pham Minh Duc for his constant guidance to me throughout the time at Can Tho
University.
I sincerely thank Assoc. Prof. Nguyen Van Hoa and Msc. Tran Huu Le have taught
and instructed me to complete this thesis.
I would like to thank Mr. Le Van Thong, and his workers in Artemia Experimental
farm Vinh Chau - Can Tho University has dedicated help and support during this
thesis achievement.
I would like to thank my classmate who encourage, support and create favorable
conditions for me during the study and implementation of the thesis.

i


ABSTRACT
The research was conducted in field conditions at Vinh Chau district, Soc Trang
province.
The use of fermented rice bran and tiger shrimp feed (early PL stage) in Artemia
intensive production as supplemented food source was evaluated. This trial was
carried out in 9 earthen pond (500m2 each) with 3 treatments as following:
Treatment I (the control known as traditional food supply in Artemia production):
Algae+chicken manure; Treatment II: Algae+chicken manure+rice bran and

Treatment III: Algae+chicken manure+shrimp feed). Artemia was inoculated at a
density of 100 inds/L and culturing for 6 weeks. Results indicated that growth and
densities of population during the culture were not statistically significant difference
among treatments (P>0.05). Similarity, fecundity also did not show statistical
difference among them even though the observed fecundity in treatment III was
highest (53±18 embryo/female), following by treatment I (43±10 embryo/female)
and treatment II was the lowest (42±9 embryo/female). The cyst yield reached
157.22±15.02 kg/ha/crop, was highest in treatment III and significantly differences
compared to other treatment (P <0.05).
As a consequence, this bring back the highest net income for treatment III
(130,689±16,445 millions/ha) and significantly differed from the remaining
treatments (P <0.05). However, return on investment (ROI, also known as rate of
profit) was highest in treatment III (3.09±0.38 times) but not significant difference
with treatment II (2,51±0,58 times), meanwhile it was differed to treatment I
(1.41±0.23 times, P<0,05). These results indecated that using tiger shrimp feed No.
0 as a supplemental feed in Artemia intensive production could lead to a better
economic efficiency than utilizing of fermented rice bran as well as traditional
feeding.

ii


TABLE OF CONTENTS

Contents

page

ACKNOWLEDGEMENTS .........................................................................................i
ABSTRACT................................................................................................................ii

TABLE OF CONTENTS...........................................................................................iii
LIST OF TABLE ........................................................................................................v
LIST OF FIGURES ...................................................................................................vi
LIST OF ABBREVIATIONS................................viError! Bookmark not defined.
Chapter I......................................................................................................................1
INTRODUCTION ......................................................................................................1
1.1 Background of the study ...................................................................................1
1.2 Objectives of the study......................................................................................2
1.3 Contents of the study.........................................................................................2
Chapter II ....................................................................................................................3
LITERATURE REVIEW ...........................................................................................3
2.1 Profile of the biological characteristics of Artemia...........................................3
2.1.1 Classification system ..................................................................................3
2.1.2 Distribution and habitat of Artemia ............................................................4
2.1.3. Life cycle of Artemia .................................................................................5
2.1.4 Feeding of Artemia .....................................................................................6
2.1.5. Reproductive traits.....................................................................................6
2.2 History research and development of Artemia..................................................7
2.2.1 In the world.................................................................................................7
2.2.2 Artemia production in Viet Nam ................................................................8
2.3 Intensive system of Artemia culture in Vinh Chau-Soc Trang ........................9
2.3.1 Siting and construction of pond..................................................................9
2.3.3 Care and pond management .....................................................................10
2.3.4 The method increase cyst yield ................................................................11
Chapter III .................................................................................................................12
METHODOLOGY....................................................................................................12
3.1 Materials ..........................................................................................................12
3.1.1 Study location ...........................................................................................12
3.1.2 Material and method .................................................................................12
3.1.3 Brine source ..............................................................................................12

3.2 Methodology ...................................................................................................13
3.2.1 Prepare the salt water................................................................................13
3.2.2 Green water in fertilized pond ..................................................................13
3.2.3 Artemia incubation ...................................................................................13
3.2.4 Method of stocking ...................................................................................13
3.2.5 Experimental set up ..................................................................................13
3.3 Data processing method ..................................................................................16
Chapter IV.................................................................................................................17
RESULTS AND DISCUSSIONS.............................................................................17
4.1 Physical parameters.........................................................................................17
4.1.1 Temperature..............................................................................................17
4.1.2 Water depth...............................................................................................18
iii


4.1.3 Salinity......................................................................................................18
4.1.4 pH .............................................................................................................19
4.1.5 Dissolved Oxygen.....................................................................................20
4.2 Growth of Artemia...........................................................................................21
4.3 Fecundity of Artemia.......................................................................................22
4.4 Population density ...........................................................................................23
4.5 Yield ................................................................................................................25
4.6 Economic Efficiency .......................................................................................26
Chapter V ..................................................................................................................28
CONCLUSIONS AND RECOMMENDATIONS ...................................................28
5.1 Conclusions .....................................................................................................28
5.2 Recommendations ...........................................................................................28
REFERENCES..........................................................................................................29
APPENDICES ..........................................................................................................31

iv


LIST OF TABLES
Table 3.1: Environmental indicators monitored during the experiment ..............15
Table 4.1: Economic efficiency (calculated on 10,000m2) ...................................27

v


LIST OF FIGURES
Figure 2.1: Distribution of Artemia in the world (Sorgeloos, 1986).......................4
Figure 2.2: life cycle of Artemia (Jumalon, ctv.,1982) ...........................................5
Figure 2.3: Artemia adult male and females carrying eggs ....................................6
Figure 2.4: The amount of cysts in the Great Salt Lake (GSL)...............................8
Figure 2.5: Area and cysts production in Vinh Chau, Soc Trang ...........................9
Figure 3.1: Pond design for Artemia culture in this experiment ..........................14
Figure 4.1: Temperature fluctuation in the morning (7am) and afternoon (2pm)
among treatments during the experiment ..............................................................17
Figure 4.2: Changes in depth during of experiment..............................................18
Figure 4.3: Changes in salinity during the experiment .........................................19
Figure 4.4: Fluctuation of pH in the morning (7am) and afternoon (2pm) in the
experiment .............................................................................................................20
Figure 4.5: Oxygen fluctuation morning (7am) and afternoon (2pm) in during of
the experiment .......................................................................................................21
Figure 4.6: Length (mm) of Artemia through out the culture ...............................21
Figure 4.7: Fecundity of Artemia over time (embryos/female) ............................22
Figure 4.8: Average number of cysts and nauplii among treatments
(embryos/female)...................................................................................................23
Figure 4.9: Density of Artemia population in the experiment period (ind/L).......24

Figure 4.10: The average number of Adult and young (nauplii + juvenile) among
treatments (inds/L) ................................................................................................25
Figure 4.11: Yield of cysts (fresh) of three treatments (kg/ha/crop)....................26

vi


LIST OF ABBREVIATIONS
0

C: Temperature C
% : Percentage
‰: Part per thousand
IND: Individual
T: treatment
STDEV: Standard deviation
HUFA: Highly unsaturated faty acid
A: Average
PL: Post larvae
Vnd: Viet Nam dong
Ind/L: Individual/litter

vii


Chapter I
INTRODUCTION
1.1 Background of the study
Artemia is a tiny crustacean species which is non selective filter feeder, they have
high nutritional value, play an important role in aquaculture (Bengtson et al, 1991;

Sorgeloos et al., 1980, 1998, 2001). In a live condition they are applying to rearing
fish, shrimp larvae, the larvae Artemia is the most widely used (Van Stappen, 1996)
in the world Aquaculture hatcheries.
In the early 1980s many countries started to develop the culture of Artemia as
Indonesia, Philippines, Vietnam, Brazil (Sorgeloos et al, 1986) but they have not
achieved successfully except in Vietnam (Nguyen Van Hoa et al.., 2007).
The success of Vietnam in production of Artemia cysts on saltworks since 1988
along with its higher prices leads activity become more sustainable than salt
production. So it has encouraged farmers in the area quickly to acquire and learn the
techniques for raising and now it has become dominated occupations in this coastal
area. In 2001, Artemia culture area was highest and over a thousand of hectares
(including areas adjacent Bac Lieu salt) and from 2005 onwards, farming area of
Vinh Chau district varied from 300-400 ha with average yield of 50-70kg/ha
(Nguyen Van Hoa, 2007).
At Vinh Chau District, Soc Trang province has about 3,000 hectares of land which
can be used to produce table salt and Artemia culture. Artemia ponds culture were
not well designed to built fertilization pond that have often face many difficulties
later on for the culture system. In addition, culturing process did not improve since
many years while water pollution is continuing, along with climate change over
time (unusual weather, short dry season. etc) and farmers sometimes with
conservative mind and more important that the lack of extension team, these have
made Artemia yields a significant reduction by years. The average yield of Artemia
in early year was around 80-100kg/ha compared to only 40-50kg/ha recently.

1


Therefore, the current situation of Artemia cysts production showed that the study to
find out a model of high-cyst yield farming (intensive system), more sustainable and
consistent with local conditions is essential.

1.2 Objectives of the study
The main objective of this study is to evaluate different supplementary foods in the
intensive pond system of Artemia culture.
1.3 Contents of the study
Evaluating the effect of fermented rice bran and tiger shrimp feed in Artemia
intensive pond.
Evaluating of economic efficiency in the intensive pond of Artemia culture.

2


Chapter II
LITERATURE REVIEW
2.1 Profile of the biological characteristics of Artemia
2.1.1 Classification system

Phylum: Arthropoda
Class:

Crustacea

Subclass:

Branchiopoda

Order:

Anostraca

family:

Artemiidae
Artemia, leach(1819)

species:

According to Sorgeloos (1986), Linnaeus called Artemia Salina in 1758 are no
longer valid in terms of classification for the crossing experiments have shown that
the difference between the populations of Artemia with closely related species are
recorded under different name.
Between the bisexual Artemia or heterozygous (population included males and
females), there are 6 sibling species of the same family are described as follows:
Artemia salina

: lymington (England, is now extinct)

Artemia tunisiana

: European

Artemia franciscana : Americas( north, central and south)
Artemia perrsimilis

: Argentina

Artemia urmiana

: Iran

Artemia monica

: Mono lake, CA-USA

3


2.1.2 Distribution and habitat of Artemia
According to Sorgeloos (1986) Artemia populations are found in more than 300
natural and artificial lakes in the world in different geographical regions. Artemia
can survive very well in natural seawater, but because the body does not have
ability to against predators, they can not grow in the sea where there is so much
competition and preys. Therefore Artemia distributed mainly in waters with high
salinity (70 ‰) which limits the predators. They can live in high salinities near
saturation (250 ‰). Artemia live in an environment with temperatures between 635°C and grow and reproduce well from 24-32.5° C, suitable pH ranged for
development is 7.5 to 8.
Artemia distributed in tropical, subtropical and temperate along the coast and
inland. In Vietnam, an adopted Artemia Franciscana, which originated from the SFB
strain (USA), being adapted almost to the Vinh Chau environmental condition after
introduction to the site since late 80’s and called Artemia Vinh Chau (or Vinh Chau
strain) , they now can grow well in the range of 80-120 ‰ salinity, temperature 2235°C. Dissolved oxygen is higher than 2 mg/litter, pH (7.0-9.0) (Nguyen Van Hoa,
2007).

Figure 2.1: Distribution of Artemia in the world
(source from: www.aquaculture.ugent.be/Education)

4


2.1.3. Life cycle of Artemia
Artemia cysts are inactive status, they are brown color, spherical bi-concave, 200300  m in dimension, they are existing in lakes, fields or be washed in saline

coastal area. When kept dry and in the absence of oxygen, the eggs will cease its
activity but do not affect the viability and hatching of eggs for years, when faced to
suitable condition, embryos would interrupt their diapause and began to metabolize
and activities (Vos and Rosa, 1980) cited by Sorgeloos, 1986.
In sea water after 24 hours, the egg membrane was broken, embryonic appearance
and is surrounded by a hatching membrane, several hours later embryos left out of
the shell, but still attached to the bottom shell (abdominal phase) called as “umbrella
stage”, shortly thereafter, the membrane was broken and hatch (hatching stage),
larvae are released and swim freely in the environment (Sorgeloos et al., 1986).

Figure 2.2: life cycle of Artemia (Jumalon, ctv.,1982)
(www.fao.org/docrep/field/003/ac420e/AC420e03.htm)

5


2.1.4 Feeding of Artemia
Artemia is a non-selective filter feeders (Reeve, 1963; Johnson, 1980; Dobbeleir et
al., 1980), and we can use a wider variety of foods (Dobbleir et al. , 1980; Sorgeloos
et al., 1986) cited by Nguyen Van Hoa et al, 2006.
The agricultural by products such as manure, rice bran, cornstarch, can be used as
supplementary food for Artemia (Nguyen Thi Ngoc Anh, 2009). In Artemia culture
in solar saltworks, farmers typically used manure (mainly chicken manure)
combined with inorganic fertilizers (urea, DAP, etc.) to stimulate the growth of
algae. Chicken manure could be directly applied into the Artemia pond as direct
food, to provide nutrients stimulate the algae growth, which intern to be filtered by
Artemia lately.
2.1.5. Reproductive trait
According to Sorgeloos (1986), while adult males sometimes used claws as holding
the belly of female so-called "coupling", Males will use 1 of 2 genital spines to

move sperms into the ovaries of reproductive females and fertilized eggs.

Figure 2.3: Artemia adult male and females carrying eggs
(Nguyen Van Hoa, 2011)
Eggs are developed in the abdomen tube of ovaries, normally fertilized eggs are
developed into free swimming larvae (ovoviviparous method) and mothers release

6


into environment. In unfavorable conditions, the embryos only developed to the
stage embryos, they would now be wrapped in a thick shell eggs and turn into cyst.
In the life cycle females can have both reproductive methods either producing
nauplii or laying eggs, each female can lay 300 eggs / time, 4 days per brood and an
average of about 1500-2500 embryonic offspring per lifetime.
2.2 History research and development of Artemia
2.2.1 In the world
Most Artemia cysts are harvested in the world, which originated from Great Salt
Lake (90%, USA) and the remainder (10%) contributed from China, Siberia, the
San Francisco area salt (U.S.), the Vinh Chau, Bac Lieu in Vietnam (Nguyen Van
Hoa et al, 2007), Colombia and East - North (Brazil), Canada (Lake Chaplin),
Australia (Shark Bay) (Stappen, 1996).
In recent years, the world Artemia culture have been extended as the need of
aquaculture development. After the first step success, cysts production began
declining in 1982. The reason was believed that the low nutrient content in the
lower pond environment lead to the decline of primary productivity. However, it
was also indicated that Artemia populations have possibly adapted to environmental
conditions, and hence adapted Artemia tended to have ovoviviparous mode in the
reproduction ( Camara and Tackaert, 1992 cited by Nguyen Van Hoa et al, 2007).
The production of Artemia with small cysts are very successful technically as in

Southeast Asia, Latin America (Sorgeloos, 1987) cited by Nguyen Van Hoa, 2007,
however, it has not been confirmed contribute significantly to the supply of cysts in
the world market since it only accounts for 2% of total annual cysts production
annually.

7


Yield(tonnes)

14000
12000
10000
8000
6000
4000
2000
0
89 9 91 9 93 9 95 9 97 9 99 0 01 0 03 0 05 0 07 0 09 0 11
9
1
1
1
1
1
1
2
2
2
2

2
2

crop(year)

Figure 2.4: The amount of cysts in the Great Salt Lake (GSL)
(Lavens and Sorgeloos, (2000), and
/>2.2.2 Artemia production in Viet Nam
Artemia is not a native species in general and Vietnam's Mekong Delta in particular
that it is entered by way of feeding the larvae rearing freshwater prawn in the early
80s of last century. However, the price was so high that Artemia farming
researchers tried to culture in saltworks of Cam Ranh, Phan Thiet, Bac Lieu, Soc
Trang. After successful trials, It is only effective in the salt field Bac Lieu, Soc
Trang.
Currently the annual cysts production in Soc Trang - Bac Lieu is estimated about 23% of world total. However, the cysts produced in these areas are small in size and
very high levels of HUFA, and these satisfy to most hatcheries, especially for
shrimp, crab and other species of marine fish larvae.
Nowadays, Artemia has become the object of popular culture cysts obtained of
coastal farmers in Soc Trang, Bac Lieu.

8


Figure 2.5: Area and cysts production in Vinh Chau, Soc Trang
(Nguyen Van Hoa, per.com.unpublished data)
2.3 Intensive system of Artemia culture in Vinh Chau-Soc Trang
2.3.1 Site selection and pond construction
Pond culture
According to Nguyen Van Hoa et al., (2007), pond should be built with bulldozers
and tractor to build the pond, avoid water leaking.

Area (2000-3000m2/pond), dike (wide 3m, high 0,6m). Intensive ponds should be
installed with aeration system to supply oxygen in the bottom of the pond, to install
a “wave-brake” system at the end of the wind direction to protect the dike and
facilitate for cyst harvesting.
Fertilizer pond
The area accounts for 20-25% of the total farming area, water depth ≥ 60 cm. If
farming area of 2 hectares or more should allocate two fertilized ponds in the green
water supply system for rotating.
2.3.2 Pond preparation
Follow the steps below when the crop started:
- Discharge water in the pond
- Remove black mud and dry pond
9


- Take seawater and evaporate for salinity increasing (to make saline water)
- Salinity ≥ 80 ‰, eliminate predators
- Stocking of Artemia
Stocking conditions
- Salinity: ≥ 80 ‰
- Turbidity: 20-25 cm
- Depth: ≥ 10 cm and be raised continously at least 20 cm after a week since
inoculation.
- Density: 100 inds/litter
- Inoculation: 6-7am in the morning or 7-8pm in the afternoon

2.3.3 Pond management
If the pond appears “water-bloom”, we need to prepare again the pond fertilization
by raking 1-2 times/day to minimize the development of lab-lab in the pond and
provide the food source for Artemia, do not rake when supplying green water

because it will limit the growth of algae. Copepods are the main predators of
Artemia, and need to eliminate them before stocking, usually to prevent tilapia
development by rised level-up the pond salinity (≥ 80%). Beside, tilapia can be
removed easily by debris-root (rotenon).
Supplemental fertilizer
Dipping directly of chicken manure in ponds in order to maintain water color with
doses of 2-3 pack/week, in the pond (2000-3000 m2); moreover, combination of
complementary foods is one of the manure to increase the cysts yield.
Feeding and aeration
Before feeding, the feed is mixed with water, and then thrown into the pond surface
where Artemia being accumulated, try to avoid feeding while supplying water or

10


raking. Besides, farmer should use aeration for 6-12h at night when high density of
Artemia or standing wind.
Dose and type of feed
Tiger shrimp feed No.0 was used as the main food source at a dose of 4-6
kg/ha/day. Food source is provided after 1 week of culture and feeding once a day
and in the evening when water temperature was cooling down.
Collection and storage cysts
Collecting cyts daily to ensure quality and to avoid thieves, cysts must be filtered,
cleaned through a fine nylon mesh (0.5 mm mesh-size) with water in pond before
selling or stored in saturated salt water (sea brine 250 ‰) for further processing.
2.3.4 Enhancement of cysts yield
To improve cysts yield of Artemia in Soc Trang, Bac Lieu, farmers have applied
method to replace alternative traditional farming processes such as increased
density, water depth and expanding the area of the pond to increase the production
of Artemia. Besides, the farmer was more interested in stage management and taken

care Artemia more carefully. They have approach more techniques, process that
they are using pond fertilization, fermented rice bran, tiger shrimp feed as food
source for Artemia.

11


Chapter III
METHODOLOGY
3.1 Materials
3.1.1 Study location
Location: Vinh Chau Experimental Farm - College of Aquaculture and Fisheries,
Can Tho University.
Address: Bien Duoi Hamlet, Vinh Phuoc commune, Vinh chau district, Soc Trang
province.
Duration: during 12/2012-06/2012 this experiment was implemented.
3.1.2 Material and method
- pH meter, oxygen-meter temperature, refractometer, turbidity (secchi disc),

binocular, microscopes, electronic balances, refrigerators.
- 250 ml triangular bottles, petri dishes, plastic pipette, buckets, plastic bottles.
- Formalin, Lugol solution .etc.
- Feed: algae (chaetoceros sp), rice bran, chicken manure, yeast breads.
- Scoop net, sampling net, brine for preservation of Artemia eggs.
3.1.3 Artemia cyst source
Vinh Chau Artemia cysts (SFB origin, USA), an inoculum provided by the
Aquaculture College and Fisheries, Can Tho University.
3.1.4 Brine source
Brine source is obtained directly from the sea (about 20-30ppt) through the process
of evaporation. The pond salinity will increase to the level up to 80-90ppt before

stocking.

12


3.2 Methodology
3.2.1 Prepare the salt water
Once seawater was taken directly to the Artemia ponds, under solar energy and
wind action, after a couple of day the salinity of natural seawater (20-30 ppt) will be
raised gradually up to 80-100 ppt (the process will take about 30 days).
3.2.2 Green water in fertilized pond
Applying of organic fertilizer (chicken manure) to create water color in ponds
fertilized with the dose of 30-50 kg/100 m3 and combine with inorganic fertilizers
(urea and DAP at a ratio of 3:1 by weight) at a dose of 2-3 g/m3, periodically
applied 1-2 times/week to stimulate algae growth. After 2-3 days green water can be
pumped into culture ponds to feed for Artemia (Nguyen Van Hoa, 2007).
3.2.3 Artemia incubation
Density incubation was from 2-5gam eggs cyst (dry) in 1 liter of water,
Provided with light continuously during incubation, incubated light buckets placed
above 20 cm (to reach the light intensity up to 2,200 lux) of hatching tanks.
-Incubation

temperature:

incubation

at

room

temperature

(25-30oC),

-Salinity: 30 ppt.
After 18-20 hours, the eggs have hatched as observed in the hatching tanks. Now,
most of them are Instar I (high adaptability to environmental changes) is very
convenient in the culture inoculation (Nguyen Van Hoa et al., 2007).
3.2.4 Method of stocking
Stocking density was 100 nauplii/L. we were usually Stocking Instar I stage in the
early morning or late evening, avoiding the direction of the wind because they can
stick into the pond by waves and wind. The water column was 10 cm.
3.2.5 Experimental set up
Experiment: To determine the effect of fermented rice bran and tiger shrimp feed
in Artemia intensive ponds (pond water level maintained at 50 cm, initial stocking
was 10cm and to be increased later).
13


The experiment was arranged with 3 treatments and 3 replicates each. Pond area is
500m2 each, stocking density 100 nauplii/L, salinity 80 ‰, 10-50 cm water depth.
Treatment

Treatment 2:

1

(control):

green

water

+

chicken

manure.

green water + chicken manure + fermented rice bran.

Treatment 3: green water + chicken manure + tiger shrimp feed No.0
.

Figure 3.1: Pond design for Artemia culture in this experiment
(Tran Huu Le,2012)

• The method provides supplementary food (for 500m2 pond)
Feeding: once/day in the afternoon (cool temperature)
Feeding rate: Daily feeding with rice bran (1kg/pond/day)( 20kg/ha/day). Shrimp
feed (0.1-0.3kg/pond/day) (4-6kg/ha/day).
Food supplementation will be adjusted to satisfy (ad-libitum) the demand of
Artemia in the pond by observing the gut (i.e. full- or empty-) of Artemia in the
ponds and pond water colors to adjust feed intake.
14


The amount of feed supplementation was recorded daily.
• Pond management
Daily observation (morning and afternoon) the Artemia health by using sampling

net and Erlenmeyer flask (250ml) picked up Artemia to observe the growth and
development, perceived ability to catch prey as well as amount of that Artemia food
intake through the gastrointestinal tract and swimming activities as well as other
symptoms to recognize the health of the population of Artemia in the pond.
Pond raking was applied twice a day in the morning and at noon to avoid
filamentous

algae development (i.e. to create socalled “lab-lab”). Algae from

fertilizer pond pumped into Artemia ponds. The water is supplied to maintain
salinity control at 80-100ppt and provided food for Artemia in experimental ponds.
• Data collection
Physical and chemical parameters:
Table 3.1: Environmental indicators monitored during the experiment
Data
facilities
time
Temperature (oC)
Depth(cm)
Salinity(ppt)
pH
Dissolved oxygen (mg/l)
Turbidity(cm

Temperature, pH Meter
Ruler
Refractometer
pH meter
Oxygen meter
Secchi dish

7am and 2pm
7am
7am
7am and 2pm
7am and 2pm
2pm

• Artemia parameters
Density of population (Ind/L) : 1 time/week, using sampling net , 200 μm mesh
size and surface area (50cm x 50cm), each pond collecting five points (four corners
points and one middle point of the pond), all samples obtained into the plastic
bucket and used the magnifying glass to count the number of Artemia.

15


Growth of Artemia (length in mm): From the first day (at the new stocking) until
day 10 (adult Artemia), each pond sampled 30 animals, 1 time/day. Using a ruler
round to measure length of Artemia.
Fecundity: 1 time/week, first sampling when Artemia started couple (about 15 days
old). The number of samples collected 30 females/pond, ovarian surgery
(dissection), and use magnifying glass (binocular) to count the number of embryos
(cysts/nauplii) per ovary
Artemia cysts yield (kg/ha/crop): Artemia cysts harvested of each experimental
will be remove impurities and weigh separately to compare the yield of each
treatment.
Economic Accounting: Profit = Total revenue - Total expenses
3.3 Data processing method
Data processed with Excel spreadsheets to get the average value, standard

deviation, standard error and Statistical program to compare the mean difference
among treatments at p <0.05.

16