Artemia culture in Southeast Asia: Special emphasis to Vietnam

By: Nguyen Thi Hong Van and Nguyen Van HoaAquaculture and Fisheries Sciences InstituteCantho University

- In most of the countries that belong to Southeast Asia like Philippine, Malaysia, Indonesia…ect Artemia culture in the salt-pan presently are notyet done except indoor culture in the hatcheries

- In Thailand, there are a few places that culturing Artemia biomass for ornamental fish industry and exporting to the Singapore.

- Artemia culture indoor in most of the hatcheries in Southeast Asia not only used as live food for shrimp and fishes but also used as a bio-filter to clean the seawater

In Viet Nam, on the year 2001, the Artemia cultured area declined more than 50% compared to last year since the cyst price loosed about ¼ and most of farmers switched into salt production

The relationship between Artemia cyst production and cultured area versus time

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

11000

12000

13000

14000

15000

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001

Yie

lds

(kg

dry

wei

ght

0

100

200

300

400

500

600

700

800

900

1000

tota

l cul

ture

d ar

ea (

ha)

Cyst (kg/dry weight) Cultured area (ha)

Large Production

This activity was done mainly under the aid of AFSI extension team (est. 60ha). Most of remaining cultured area were self-management by experienced farmers (est. 360to 370ha).

- The yields varied from 20kg to more than 100kg/ha/crop- Average yields: 45kg/ha/crop

Extension activities of AFSI

Training at AFSI

Transporting nauplii to farmers

Advantages:Culture technique were gradually transferred to the farmers and the culture area are expanding by time.To decrease the working pressure on extension team when the culture area are expanded.

Disadvantages:Less experienced or new farmers normally have poor production.Farmers usually manage the production by their feeling and experiences rather than their understanding on biological processes that appear in the ponds.

Some characteristics on management of large production:- Salinity: 70 ppt upwards- Water level: normally shallow (2-3cm at the beginning and 5-10 at the end of the culture)- Stocking densities: high: 200-300 nauliar/litter. Farmersprefer to stock with very high densities and after few daysthe densities were lowered by transferring Artemia to another pond.

* Problem: - Water levels are very shallow, shortage of food - Salinity are slowdown dramatically - Copepode population grow quickly - Macro-algae and Lab-lab development

Survival is very low

- Fertilized pond are not well management- Heavily rely on supplement food: Rice bran, chicken manures

Lab-lab

Seaweed

Chicken manures

Research at AFSI

Sampling

Observation

Collected samples

Alga culture

Turbid measure

Prepare for sampling

Research

1. Wild algae as food for Artemia.

3 algae species are used to test on growth and survival of Artemia:+ Chaetoceros Best growth and survival+ Nizchia can survive but slow growth+ Oscillatoria no growth, died after few days

2. Control problem of ‘water bloom’ in Artemia pond.

Water bloom (algae bloom) appear

Pond with poor organic matters

Ponds with richorganic matter

Less Always

Stocking densities

High yields

60-70ind/l 120-150ind/l

3. Comparison life characteristics of Artemia between field and lab conditions

Water flow

A: bottle coverred with net at 3 sides

B: rack for individual culture in pond

C: Rack was hung in the water column of the culture ponds

Figure 2: individual culture system in pond

+ Pair culture in the laboratory: The animals were fed with water from the culture pond, the culture medium was maintained similar as in the pond

Results:

The reproductive characteristics (reproductive mode, fecundity)- Pond culture (sampling)- Pair culture in pond- Pair culture in the laboratory

No sinificant differences

4. Effect of using Artemia nauplii of successive generations on cyst production- Objective: Investigating the relationship of cyst yields and successive generations (P, F1, F2, F3)- Principle:

Inoculum (P=cysts) 14 days

Naupliar transferF1

F2F314 days

14 days

Naupliar transfer

Naupliar transfer

Result:- Survivals: After 7days of the inoculation: 50-60%

After 9-10 days (reach adult sizes): 25-40%

The major reason for this decline could be the food availability in pond and environmental stress (especially is high temperature).

- Reproductive characteristics:+ Fecundity: varies from 30 to more than 100

offspring and not much different between generations+ Number of female - bearing nauplii do not

follow any rule but number of female-bearing cysts are follow the same rule for each generation.

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

120.0%

1 2 3 4 5 6

WEEKS

SU

RV

IVA

L (%

)

P

F1

F2

0.0%

20.0%

40.0%

60.0%

80.0%

100.0%

120.0%

1 2 3 4 5 6

weeks

su

rviv

als

(%

)

P

F1

F2

Proportion of number of female-bearing cysts in the population between each generation

0

20

40

60

80

100

W2 W3 W4 W5 W6

%

P

F1

F2

The cyst yields: (kg/ha/5week) 1999-2000 2000-2001 2001-2002

Parent 60.06 53.01 24.58F1 68.84 46.2 5.43F2 81.07 20.98 28.75F3 12.47

The cyst yields were largely changed over years, beside the unknown factors that need to be investigated (environment stress, genetics…). Other factors also might influence to cyst production included:

  +    Seasonal reproduction of Artemia  +     Food availability + Temperature Most importance

Future researchSuitable pond management fit to different kind of pond bottom soil, especially emphasizing to the proper stocking densities and fertilization.Effects of biotic factor (food availability), abiotic factor (temperature) to reproductive characteristics and cyst production of successive generations Effect of quality and quantity of food (algae) on Artemiacyst production of successive generations .Genetic variation and heritable traits of Artemia between generations (P, F1, F2, F3).

Thanks for your attention