CANADA FUNDS-IN-TRUST FAO/GCP/MAL/009/CAN March 1986

A report prepared for the
Besut Integrated Fisheries Development Project
based on the work of

Niwes Ruangpanit
Consultant
(Aquaculture)

This report was prepared during the course of the project identified on the title page. The conclusions and recommendations given in the report are those considered appropriate at the time of its preparation. They may be modified in the light of further knowledge gained at subsequent stages of the project.

The designations employed and the presentation of the material in this document do not imply the expression of any opinion whatsoever on the part of the United Nations or the Food and Agriculture Organization of the United Nations concerning the legal or constitutional status of any country, territory or sea area, or concerning the delimitation of frontiers.

FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
Rome, 1986

Hyperlinks to non-FAO Internet sites do not imply any official endorsement of or responsibility for the opinions, ideas, data or products presented at these locations, or guarantee the validity of the information provided. The sole purpose of links to non-FAO sites is to indicate further information available on related topics.

This electronic document has been scanned using optical character recognition (OCR) software. FAO declines all responsibility for any discrepancies that may exist between the present document and its original printed version.

TABLE OF CONTENTS

1. INTRODUCTION AND TERMS OF REFERENCE

1.2 Counterpart staff

2. WORK PROGRAMME

3. WORK DONE

3.1 Training on the Mass Culture of Food Organisms

3.1.1 Tetraselmis sp. culture
3.1.2 Rotifer mass culture

3.2 Transfer and Conditioning of Lates calcarifer Broodstock for Breeding Purpose

3.2.1 Transfer of broodstock
3.2.2 Care of mature brood stock
3.2.3 Spawning and eggs collecting

3.3 Training for Finfish Hatcheries

3.3.1 Trials in primary larval rearing
3.3.2 Trials in secondary larval rearing

3.4 Nursing Seabass Fry Up to Fingerling Size for Cage Culture

3.5 Finfish Hatchery Desigh and Specification

3.6 Training for Marine Shrimp Hatchery

3.6.1 Trials in including ovary maturation of Penaeus monodon in captivity
3.6.2 Trials in rearing shrimp larvae
3.6.3 Trials in nursing post-larvae

4. CONCLUSION AND RECOMMENDATION

4.1
4.2

4.2.1
4.2.2
4.2.3
4.2.4
4.2.5
4.2.6

5. REFERENCES

Appendix 1 CHRONOLOGICAL LIST OF CONSULTANT'S ACTIVITIES

Appendix 2 HATCHERY FACILITIES FOR PRACTICAL COUNTERPART STAFF AT TANJONG DEMONG BESUT HATCHERY

Appendix 3 FISH HATCHERY LAYOUT, TYPES 1 AND 2

Appendix 4 ITINERRARY AND LIST OF PERSONS MET

LIST OF TABLES

1. Work programme agreed by the author and the project manager (22 June– 21 October 1985)

2. Media used to culture Tetraselmis starter

3. Media used to mass culture Tetraselmis

4. Information of brood stock (Lates calcarifer) raised in the spawning tank

5. Natural spawning of seabass (Lates calcarifer) in spawning tank (150 t capacity), July-October 1985

6. Survival rate of 15 day old larvae of seabass rearing in 5 t round fibreglass tanks

7. The survival rate of 30 day old (1–1.5 cm) seabass fry nursing in the secondary rearing

8. Type and relative amounts of food given at various stage of the seabass larvae

9. The production of larvae and fry of seabass and their distribution period July-October 1985

10. The growing and survival rate of the seabass fingerling nursing in the 1.2 × 3 × 0.6 m fibreglass tank

11. The amount food given to the fish fry during on nursing period

12. The body weight of males and females Penaeus monodon used for practice in inducing ovaries maturation

13. The results of inducing avaries maturation of Penaeus monodon in captivity

14. The survival of Penaeus monodon postlarvae during the practical training

15. Feeding levels of each larvae stage of Penaeus monodon

16. Results of nursing Penaeus monodon postlarvae

LIST OF FIGURES

1. Chart showing management method for seabass nursing tank within the first 40 day period

1. INTRODUCTION AND TERMS OF REFERENCE

The Malaysian Government, with technical assistance from the Food and Agriculture Organization of the United Nations and financial aid from the Canadian International Development Agency (CIDA), has been engaged in the Besut Integrated Fisheries Development project (GCP/MAL/009/CAN) whose main objective has been to assist in the improvement of the socio-economic status of those engaged in small-scale fisheries. Project activities include the production of fry of both marine and freshwater prawns and fish at the Tanjong Demong Hatchery, and the development of aquaculture in Besut.

As part of the project operations, FAO assigned Niwes Rwangpanit as aquaculture consultant from 22 June to 21 October 1985 with the following terms of reference:

• Management and operation of the Tanjong Demong Hatchery in conjunction with the local counterpart staff to enable them to take over the running of the hatchery eventually.

• Preparation and conditioning of existing broodstock at Kuala Setiu for transfer to Tg. Demong Hatchery for breeding purposes.

• Collection and conditioning of Lates calcarifer and Penaeus monodon broodstock for breeding at the hatchery.

• Development of techniques and demonstration of the production of fry of Lates calcarifer and post-larvae of P. monodon.

• Development of techniques for raising fry of Lates calcarifer up to fingerling stage for use in cage culture.

• Any other duties connected with the breeding of finfish and prawns.

This report details the training given to the counterpart staff, covering commercial mass production and related activities in hatchery operation. Also included are theoretical aspects of various organism cultures, plus practical and technical management techniques specific to this hatchery.

1.2 COUNTERPART STAFF

2. WORK PROGRAMME

A breakdown of the work programme agreed by the consultant and the project manager, and the amount of time devoted to each phase are shown in Table 1. The facilities available are listed in Appendix 2. Activities were carried out with the main purpose of giving practical training to the project staff with emphasis on the finfish hatchery. Informal lectures and discussions were held during the course of daily activities.

3. WORK DONE

3.1 TRAINING ON THE MASS CULTURE OF FOOD ORGANISMS

An area of major concern in larval rearing of finfish and shrimp in a hatchery system is the provision of suitable food sources. Unicellular micro-algae and some zooplankton such as rotifer have been cultured as food for marine shrimp and finfish larvae. Therefore, a technique of culturing adequates of these living organisms is necessary.

3.1.1 Tetraselmis sp. Culture

Tetraselmis sp. is green flagellate which can be cultured in natural sea water between 15 and 36 ppt and grows at temperatures between 15° and 33°C under natural light conditions. As the temperature of the outdoor tank for culturing phytoplankton was between 26° and 33°C, Tetraselmis was suitable for culturing in this hatchery. Moreover, culturing only Tetraselmis could be used for feeding both shrimp and finfish larvae.

The first stage culture in 2 1 flasks were maintained in the algal culture room and continually exposed to light provided by ordinary fluorescent lamps. After three days, they had reached a density of 100 000 cells/ml and could provide the supply for the intermediate stage of culture. The nutrients added are shown in Table 2.

Glass aquaria of 30 1 capacity were used for the intermediate stage culture. Seawater in each aquarium is inoculated with 3 1 of starter obtained from the previous stage and propagated under sunlight. A density of 80 000–120 000 cells/ml could be obtained in 3–4 days. In the last stage, 500 l, 1 000 l annd 5 000 l were used for the mass culture; a one-third inoculation was applied in each tank. The nutrient added are shown in Table 3. After 3 days Tetraselmis could be harvested to feed the zoea stage of marine shrimp and rotifer.

3.1.2 Rotifer Mass Culture

There are many species belonging to class Rotiferae, but the most suitable for mass culture appears to be Brachionus plicatilis. It is a very important and indispensable food for marine finfish larvae and has also been used as food for the mysis stage of penaied prawn.

Rotifer was cultured in 10 t tanks. Tetraselmis was first cultured to reach 80 000–100 000 cells/ml. Starter was added at a density 10–20 ml. Rotifer density reached 80–100/ml after 5 days. It was then ready for harvesting by syphoning the water from the rotifer cultured tanks through 63 micron mesh bags, leaving half of the original volume to serve as starter for the next batch. Then Tetraselmis (80 000–100 000/ml) were added to the rotifer cultured tanks to the 10 t level in order to grow the next batch of rotifer. Dry baker's yeast was added as supplement food at the rate of 0.5g/million rotifer when water in rotifer culture tanks became clear. Each rotifer culture tank was used for culturing from 7 to 10 days after which the tank should be cleaned and culture started.

3.2 TRANSFER AND CONDITIONING OF LATES CALCARIFER BROODSTOCK FOR BREEDING PRUPOSE

3.2.1 Transfer of Broodstock

On 9 July 1985 seabass broodstock were transferred from the cage net at Kuala Setiu to the spawning tank. It is a round tank, 10 m diameter and 2 m depth. Thirty fish were kept in the tank, female:male sex ratio 3:2. Male and female seabass adult fish can be determined by the shape of male which is more slender and generally weighs less than the female spawner even at the same total length. The abdomen of the male does not bulge like that of the female spawner, and the body is thinner than that of the female. The scale around the anal area of the male becomes thicker than that of the female. In the spawning period the female spawner carries large quantities of eggs causing the abdomen to bulge. With slight pressure by hand the eggs will flow out. For the male, if the abdomen is pressed the milt comes out from the urogenital opening. The reared broodfish should be ready to start spawning at the end of their third year when they attain about 3–5 kg body weight. The best milt comes from males of 2–4 years whereas the females are not used before their third or fourth year. Approximately one month before the spawning season the parent fish should be moved from the cages into the spawning tank.

3.2.2 Care of Mature Broodstock

Water supply in the spawning tank was seawater with salinity 30–32 ppt. Every day 80–100 percent of the total volume of water was drained out and renewed with clean seawater. Sufficient aeration was always supplied to the spawning tank.

Fish sardine and Caranx were used for feeding the spawners. They were fed once a day after changing the water. The daily feeding rate was approximately 1–2 percent of their body weight (Table 4). Since the spawners were kept in the tank for a long time they were sometimes damaged by bacteria and protozoa which resulted in the fish refusing food. They were then treated with 1–2 ppm KMnO₄ solution for 1 hour and formalin 20 ppm. The treatment was continued for about 3–4 days. When the fish began to eat food again antibiotics such as tetracycline hydrochloride was applied at 10–20 mg/kg of body weight per day for 3–4 days continually.

3.2.3 Spawning and eggs collecting

The fish began to spawn on 20 July 1985, 11 days after transfer to the spawning tank. This is the first successful attempt to induce seabass reared broodstock to spawn in captivity in Malaysia. Spawning occurred between 19.00 and 23.00 h between the fourth and the twelfth day of both full moon and new moon. The duration of spawning each time was 3–5 days. The fertilized eggs floated on the surface while the unfertilized ones sank to the bottom. The floating fertilized eggs were scooped out from the spawning tank and placed in the hatching/rearing tanks. (The production of fertilized eggs, newly hatched larvae, is shown in Table 5). After fertilized eggs are removed, the spawning tank should be cleaned and new seawater supplied in preparation for future spawning activity.

3.3 TRAINING FOR FINFISH HATCHERIES

The process of larval rearing was divided into two stages. The first, “primary rearing”, extended from hatching to a larval size of 4–6 mm in total length or 10–15 days after hatching. The second step, “secondary rearing”, covered the period up to 6–15 mm size or 16–35 days after hatching.

3.3.1 Trials in primary larval rearing

Fertilized eggs were placed in round fibreglass tanks, 3 m and 0.9 m diameter depth. Each tank was filled with seawater with 30 ppt salinity and aerated continually. The eggs hatched out in 17 hours at an average water temperature of 27°C. After hatching, aeration of the tanks was stopped for a few minutes so that the sediment of developed embryos and other dirt could be siphoned out. The larvae stocked in each tank are shown in Table 6. Every morning 30 percent of seawater was changed and replaced with new seawater. Feeding with rotifer Brachionus plicatilis commenced on the second day after hatching corresponding with the completion of mouth opening which was generally observed in the afternoon of the second day. Rotifer should be given in adequate amounts up to 15 days of age. A rotifer density of 10–20/ml was required for one rearing tank. Green water, Tetraselmis sp., was added to the rearing tanks during the period of rotifer feeding. Brine shrimp fed to the larvae together with rotifer from 8 days of age. The larvae were reared in these tanks until 15 days old. They were then distributed in nursing tanks for the second stage, “secondary rearing”.

Of the 1 950 800 newly hatched larvae used in rearing, 440 000 larvae survived to 15 days of age (Table 6). Because of the limited nursing tanks, some of these larvae were kept for further trials in secondary rearing, while the remainder was sent for nursing at the other hatchery and released into natural water (Table 9).

3.3.2 Trials in secondary larval rearing

When the larvae were 15 days old they were distributed for nursing in the rectangular figreglass tanks (1.2 × 3 × 0.6 m) and round fibreglass tank (diameter 3 × 0.9 m depth); stocking density in each tank is shown in Table 7. These larvae were fed with brine shrimp nauplii. The larvae could be trained to feed on dead food such as minced fish meat from the twenty-fith day onward. All food was given gradully, according to the type and amount (see Table 8).

Changing the water is necessary in larval rearing. The rate and frequency of exchange depend on the water quality and feeding period. At this hatchery, water in the rearing tanks was changed about 50 percent every day. Detritous, brine shrimp egg shells and left-over food were siphoned out every day in order to keep the bottom of the tank in good condition. The normal practice of water management is shown on Figure 1.

Size-grading is essential to minimize the decrease in larvae due to cannibalism. Fish production will be greatly affected if fry of different sizes are stocked together; and cannibalism will occur after they are two weeks old. The material normally used for grading consists of plastic containers punched at the bottom with holes of diameter 2, 3.5, 5, 6 and 7 mm. The frequency of grading depends on the variation observed daily in the size of the fish. Usually they should be graded within 5–7 days at a time (at intervals of 5–7 days).

Table 7 shows that of the 110 000 larvae (15 days old) kept for trials in secondary rearing, 91 200 fry (1–1.5 cm) survived. The total production of larvae and fry and their distribution are shown in Table 9.

3.4 NURSING SEABASS FRY UP TO FINGERLING SIZE FOR CAGE CULTURE

Up to the present fish farmers rearing seabass fry from 2 cm up to fingerling size (5 cm and over) in the nursing cages have faced many problems. One of the main difficulties is the high mortality (95 percent) of juvenile seabass during the nursing period. In spite of good management, mortalities have still remained at 30–50 percent. The high mortalities can, therefore, affect the economics of seabass culture. To the country where the fry have to be imported, and for remote areas far from the fry supply centres, the high cost of fingerlings for grow-out operations can thus be seen as a potential major constraint confronting the future development of seabass culture in the region. There are several causes of nursery mortalities: cannibalism due to high stocking density and different sizes, water quality, dietary deficiency and disease infection.

Five thousand fry (1.2–1.5 cm initial stocking size) were kept for nursing trials up to fingerling size. They were nursed in rectangular fibreglass tanks (1.2 × 3 × 0.6 m). The initial stocking density was 2 500 fry/tank (694 fry/m² or 1 388 fry/m³). After each grading the stocking density were reduced to the optimum level (Table 10).

Water quality management: The quality of the water in nursery tanks depends on several factors, such as concentration of metabolite and the food remaining at the bottom. To maintain good water conditions in the nursery tanks, the water was changed 100 percent twice a day, and the remaining food siphoned out.

Feed and feeding method: Dietary deficiency and feeding bad quality food resulted in a stock of fry with retarded growth and susceptible to disease. The trash fish diet presently used for nursing seabass may be in bad condition, the degree of spoilage of the materials used suggests at least a deficiency of vitamins and trace nutrients and also unhygienic conditions. To avoid these problems the diet selected for nursing the seabass used only good quality fish suitable for human consumption. The fish meat was minced and 3 percent vitamin mixture and mineral added. The fish fry were fed four times a day at 9.00, 12.00, 15.00 and 18.00 h. The amount of food given was adjusted depending on fish growth (Table 11).

Grading of fry: To reduce mortality caused by cannibalism, the grading of fry into size groups is essential. The process of separating the fry into different sizes is by using a grader, a basin perforated with holes of a certain size. Graders with hole diameters of 8, 9 and 10 mm were used progressively as the fry grew. These grading diameters can separate the fish sizes at 3, 4 and over 5 cm respectively. The frequency of grading depends on the variation observed daily in the size of the fish. Usually they should be graded within 1–2 weeks at a time.

The nursing of the fry up to fingerling size and their survival are shown in Table 10. All the fry grew through 5 cm within 6 weeks with a survival rate of 93.82 percent.

3.5 FINFISH HATCHERY DESIGN AND SPECIFICATION

The Department of Fisheries requested a design and specification for a finfish hatchery to be set up at Tanjong Demong, Kuala Besut (and possibly elsewhere). The size and capacity of the hatchery will depend on government policy and function of the hatchery. For convenience the hatchery has been designed to produce fry (1–1.5 cm) at the rate of about 1 million/year. The basic culture tanks required are the following:

The design criteria for a finfish hatchery are as follows:

1. Rearing tanks and nursery tanks are 1 × 2 × 8 m holding 0.8 m of water or volume of 12 m³. About 50 percent of the water in each tank is changed daily. One-day-old larvae are stocked in these rearing tanks and held for 14–15 days. Each tank is stocked with 360 000 larvae, a stocking density of 30 000/m³. About 1–1.5 million newly-hatched larvae are required per cycle. After 14–15 days the larvae are transferred to nursery tanks and held until they grow to about 1–1.5 cm. Each tank is stocked with 30 000–36 000 larvae, a stocking density of 2 500–3 000/m³. Estimated production of 1–1.5 cm fry 1 month age is 1 500–2 000/m³. Production of fish fry would be 180 000–240 000/cycle and total production about 1.08–1.44 million/ year (estimated 6 cycles/year).

2. Rearing and nursery tanks should have 50–70 percent clear roofing and food organism culture tanks constructed out-of-doors.

3. The ratio of rearing tanks, rotifer culture tanks and green water culture tanks is approximately 1:2:4.

4. The seawater supply tank is 2 × 5 × 10 m. It should be elevated at least 1 m above the culture tanks. Seawater pumping to increase the pressure supply to the culture tanks may be installed if necessary.

5. The seawater reservoir should carry half the volume of the total of the culture tanks. In the case of seawater needing to be treated before use for culturing, reservoir volume should be 1–2 times the volume of the culture tanks.

6. The seawater pipe should be 4–5 inches in diameter and the water inlet PVC valves 1–1.5.

7. The aeration supply in the culture tanks should be strong enough to circulate and agitate the food organisms to remain suspended with a uniform distribution. Following are the data of an air blower suitable for the hatchery:

3.6 TRAINING FOR MARINE SHRIMP HATCHERY

3.6.1 Trials in including ovary maturation of Penaeus monodon in captivity

About 27 shrimp (13 from the wild and 14 from the pond) were held in the round fibreglass tank (3 m diameter and 90 cm depth). One eye of each female was pinched off with the fingernails before being released into the tank. Ten females and 17 males were released on 18 July 1985 and ended on 20 August 1985: the body weights of both males and females are shown on Table 12. Seawater flowed continually 24 hours daily into the maturation tank which allowed a complete exchange 1–2 times each day. Aeration was provided to maintain a dissolved oxygen concentration of more than 5 ppm. Temperature range throughout the operation was from 26° to 29°C, and salinity level 30–31 ppt. The tank surface was covered with a black cloth to prevent development of benthic algae and also to decrease the solar light for non-burrowing species.

The maturation diet consisted of cockle, squid and cow liver in a ratio of 4:5:1. The daily feeding rate was from 5 to 10 percent net weight of the shrimp biomass and they were fed twice daily, morning and afternoon. The ovarian development was examined after ablation by using a waterproof handlight which permitted viewing the ovaries without handling. Examination began 3 days after ablation. When the colour, shape and texture of the ovaries indicated readiness to spawn, a shrimp was removed from the maturation tank and placed into the 200 1 spawning tank. After the shrimp had spawned, it was put back into the maturation tank. Ten gravid females were used in the experiment but only 6 gave vital eggs. Out of the 6 gravid females only 3 gave healthy larvae that could be reared to early post-larval stage. The other, gave weak larvae all of which died at zoea 1. Each gravid female gave on the average 100 000–220 000 nauplii (Table 13).

3.6.2 Trials in rearing shrimp larvae

As gravid females from the natural water were not available, the trial in rearing shrimp larvae had to use the gravid females from induced ovary maturation. Only 3 gravid females came from the maturation tank in this experiment. The nauplii were reared to post-larval stage in round fibreglass conical tanks of approximately 1 300 1 (Table 14). The metamorphosis of the nauplii larvae to the zoea stage occurred on the second day after hatching and they began to feed. Tetraselmis were transferred to the larval rearing tanks one day before the nauplii metamorphosed into zoea. Tetraselmis served as food for zoea stages I-III. Bread yeast was added as supplementary food in the afternoon when it was anticipated that the Tetraselmis was insufficient for feeding the larvae. When all the larvae had reached mysis stage, rotifer were added to the tanks. The number of rotifers added depended on the density of the larvae. Each mysis larvae consumed about 200–300 rotifers per day. After 3 days, the mysis metamorphosed into the postlarval stage and brine shrimp were fed in the early stage of post-larvae. When the larvae developed into mysis, water quality was maintained by a daily water exchange rate of 50 percent and by siphoning out the detrital matter from the bottom of the tanks. Post-larvae were harvested from the rearing tanks three days after the larvae changed from mysis to post-larvae because the rearing tanks in this hatchery were designed for rearing only larvae and early post-larvae. The survival of the post-larvae reared in these tanks is shown in Table 14 and the feeding level of each larvae stage was shown in Table 15.

3.6.3 Trials in nursing post-larvae

Nursing the post-larvae is best done in nursing ponds or larger tanks where postlarvae can be sparsely stocked and where hiding places are available. Nursing in small tanks with a high stocking density results in high mortality levels due to cannibalism. Under such constraints as lack of nursing ponds and large tanks, they were nursed in the existing rectangular fibreglass tanks (3.6 m² 60 cm depth). Initial stocking rates of post-larvae for nursing were shown in Table 16. They were fed with finely chopped boiled squid three times a day. Eighty percent of water in nursery tanks was changed daily and the remaining food siphoned out every morning. They grew to an intermediate size (2 cm) for stocking in grow-out ponds within 3 weeks. The results of nursing are shown in Table 16.

4. CONCLUSION AND RECOMMENDATIONS

4.1 The work done from July to October 1985 consisted of demonstration, training and practising the techniques of care of seabass broodstock, natural spawning seabass in captivity, hatchery management, larval rearing, nursing fry up to fingerling stage, culture of food organisms (both phytoplankton and zooplankton), induced ovary maturation of Penaeus monodon, shrimp larvae rearing and post-larval nursing.

4.2 Following are the recommendations for future hatchery activities.

4.2.1 Seabass broodstock should be reared in the spawning tank all the year round to observe the actual spawning period in order to obtain more information for programming the hatchery operation.

4.2.2 Every spawning period, seabass spawners produced several million eggs. They were kept in this hatchery for larval rearing. Then the fertilized eggs or newly hatched larvae could be distributed to other hatcheries, private or governmental.

4.2.3 To obtain good quality fertilized eggs and healthy larvae, the broodstock should be changed every 4 months if possible.

4.2.4 Seawater used for culturing food organisms and larval rearing should be treated with calcium hypochlorite and dechlorinated with sodium thiosulfate to prevent contamination with undesirable organisms and disease infection.

4.2.5 The seawater main pipe to the culture tanks should be increased to 4–5 inches to provide the necessary pressure to feed seawater into several tanks at the same time.

4.2.6 The current production of 1.5 cm seabass fry is 50 000–80 000; the production of fry can be increased to 100 000–140 000 by adding another 14 food organism culture tanks (1 × 5 × 10 m).

5. REFERENCES

Anderson, D.W., and Noel Smith. 1983 The culture of larval food at the Oceanic Institute, Waimanalo, Hawaii. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 15–41

Aquacop. 1983 Constitution of broodstock maturation, spawning and hatching systems for penaeid shrimp in the Centre Oceanologique du Pacifique. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 105–121

Aquacop. 1983 Penaeid larval rearing in the Centre Oceanologique du Pacifique. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 123–127

Fox, J.M. 1983 Intensive algal culture technique. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 15–41.

Kosutarak, P. 1984 Effect of supplemental vitamin on feeding fish meat to juvenile seabass, Lates calcarifer. Report of Thailand and Japan Joint Coastal Aquaculture Research Project (Apr. 81-March 84) No. 1 pp. 7–12.

Liao, I.C., Huei-Meei Su and Jaw-Hwa Lin. 1983 Larval food for Penaeid prawns. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 43–69.

Liao, I.C., and Yi-Peng Chen. 1983 Maturation and spawning of Penaeid prawns in Tungkang Marine Laboratory, Taiwan. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 155–159

L.C., William. 1982 Management of the nursery of seabass fry. Report of training course on seabass spawning and larval rearing SCS/GEN/82/39, pp. 34–37

Maneewongsa, S. and T. Tattanon. 1982 Care and maintenance of seabass broodstock. Report of training course on seabass spawning and larval rearing, SCS/ GEN/82/39, pp. 42.

Maneewongsa, S. and T. Tattanon. 1982 Collection and Selection of seabass spawners. Report of training course on seabass spawning and larval rearing, SCS/GEN/82/39, 17 p.

Maneewongsa, S., T. Tattanon, and T. Watanabe. 1984 Studies on the seed production of the seabass, Lates calcarifer. I Present status of production and some results of rearing in 1982 at NICA. Report of Thailand and Japan Joint Coastal Aquaculture Research Project (April 81-March 84) No. 1 pp. 13–35

Mc Vey J.P. and Joe M. Fox. 1983 Hatchery techniques for penaeid shrimp utilized by Texas A & M-NMFS Galveston Laboratory Programme. Handbook of Mariculture, Volume 1: Crustacean Aquaculture, pp. 129–154

Pechmanee, T., S. Maneewongsa and N. Ruangpanit. 1984 Mass production of rotifer, Brachionus plicatilis, at NICA in 1983. Report of Thailand and Japan Joint Coastal Aquaculture Research Project (Apr. 81-March 84) No. 1 pp. 111–115

Ruangpanit, N. 1982 Report of Consultancy on Hatchery Techniques of Brackishwater shrimp and Fin fish Hatchery in Malaysia, BOBP, GCP/RAS/040/SWE

Ruangpanit, N., S. Maneewongsa, and T. Tattanon. 1984 Induced ovaries maturation and rematuration by eyestalk ablation of Penaeus monodon Fab. collected from Indian Ocean (Phuket Province) and Songkhla Lake, NICA., Tech. paper No. 4/1984, 13 p.

Ruangpanit, N., T. Tattanon and P. Kraisingdeja. 1984 The study on the larval rearing of Penaeus merguiensis de Man, NICA. Tech. paper No. 5/1984, 14 p.

Ruangpanit, N., S. Maneewongsa and T. Pechmanee. 1984 Fry production on seabass, Lates calcarifer, at NICA in 1983. Report of Thailand and Japan Joint Coastal Aquaculture Research Project (Apr. 81-March 84) No. 1, pp. 7–12

Tattanon, T., and S. Maneewongsa. 1982 Larval rearing of seabass, Report of training course on seabass spawning and larval rearing, SCS/GEN/82/39, pp. 29–30

Tattanon, T. Hatchery Techniques of Penaeid Shrimp and seabass. 1984 A Report proposed for the Government of Malaysia, FAO/UNDP/MAL/78/018, 26 p.

Tattanon, T. and S. Maneewongsa. 1984 Natural spawning of seabass under controlled environment. Report of training course on seabass spawning and larval rearing, SCS/GEN/82/39, 19 p.

Watanabe, T. 1982 The production of food organisms with particular emphasis on rotifer. Report of training course on seabass spawning and larval rearing, SCS/GEN/82/39, pp. 26–28

¹ Normally expressed in “weight” rather than in length to show the dailyration and its percentage to the total biomass

Fig. 1 Chart showing management method for seabass nursing tank within the first 40 day period

Appendix 1
CHRONOLOGICAL LIST OF CONSULTANT'S ACTIVITIES

Appendix 2
HATCHERY FACILITIES FOR PRACTICAL TRAINING COUNTERPART STAFF AT TANJONG DEMONG BESUT HATCHERY

Appendix 3

FISH HATCHERY LAYOUT: Type 1

FISH HATCHERY LAYOUT: Type 2

1. Rearing tanks 1×2×8 m

2. Nursery tanks 1×2×8 m

3. Rotifer culture tanks 1×4×8 m

4. Green water culture tanks 1×4×8 m

5. Sea water supply tank 2×5×10 m

6. Resevoir∅10×2 m

Appendix 4
ITINERARY AND LIST OF PERSONS MET

Persons met