Appendices

APPENDIX A
LIST OF PERSONALITIES MET

Mr. G. Abesamis
San Miguel Avenue
6766 Ayala Avenue
Makati, Metro Manila
Philippines

Mr. Hans Ackefors
University of Stockholm
10691 Stockholm
Sweden

Dr. David Aiken
Biological Station
Saint Andrews NB EDG 2X0
Canada

Mr. Dean Akiyama
541 Orchard Rd. #11–03
Liat Towers 0923
Singapore

Mr. Edgar Arellano
ESPOL
Guayaquil, Ecuador

Dr. Jim Avault
1058 Oak Hills Pkwy
Baton Rouge LA 70810
United States

Mr. Jessie Banno
Oceanic Institute
Waimanalo HI 96795
United States

Dr. Lorena Barck
University of Hawaii
1800 East West Road
Honolulu HI 96822
United States

Dr. John Bardach
Honolulu, Hawaii
U.S.A.

Dr. Claude Boyd
203 Swingle Hall
Auburn AL 36830
United States

Dr. Robert Brick
P.O. Box 1346
Kaneohe HI 96744
United States

Dr. James Brock
Dept. of Land & Natural Resources
335 Merchant St., Room 359
Honolulu HI 96813
United States

Dr. Homer Buck
220 W. Porter
Salem IL 62881
United States

Mr. William Cahill
30 Meadow Glen Road
Northport NY 11768
United States

Mr. Robert Cantrell
14 Aulike St. #704
Kailua HI 96734
United States

Mr. John Castille
2705 F Saint Joseph
Corpus Christi TX 78418
United States

Mr. William Chauvin
417 Eliza St.
New Orleans LA 70114
United States

Dr. Daniel Cheney
15916 NE 1st Street
Bellevue WA 98008
United States

Dr. Kenneth Chew
School of Fisheries WH-10
University of Washington
Seattle WA 98195
United States

Dr. Dan Cohen
39/5 Meir Nakar St.
Jerusalem
Israel

Mr. Harry Cook
Ocean Ventures, Inc.
Rt 3, Box 80D
Port Lavaca TX 77979
United States

Mr. Peter C. Cook
Ocean Ventures, Inc.
Rt 3, Box 80D
Port Lavaca TX 77979
United States

Dr. John Corbin
335 Merchant Street, Suite 359
Honolulu HI 96813
United States

Mr. Harry Daniels
Swingle Hall
Auburn University AL 30849
United States

Dr. E.M. Donaldson
4160 Marine Drive
West Vancouver BC V7V 1N6
Canada

Ms. Kelen Dunford
Natural Energy Laboratory of Hawaii
P.O. Box 1749
Kailua-Kona HI 96745
United States

Dr. James Ebeling
53–567 Kam Hwy #304
Hauula HI 96717
United States

Dr. Hillary Egna
CRSP Office of Int1 Res & Dev
Oregon State University
Corvallis 0R 97331
United States

Ms, Eleanor Enriquez
18 Tanguile Street
Project 7
Quezon City 3008
Philippines

Mr. Arlo Fast
P,0, Box 1346
Kaneoho HI 96744
United States

Mr. Cayetano Ferreria
Don Tim Development Corporation
5468 South Superhighway
Makati, Metro Manila
Philippines

Dr. R.B. Fridley
Aquaculture Fisheries Program
University of California
Davis CA 95616
United States

Mr. Takuji Fujimura
98–710 Kaamilo Street
Aiea HI 96707
United States

Mr. William Garcia
P.O. Box 2232
Manila
Philippines

Dr. John Glude
2703 West McGraw
Seattle WA 98199
United States

Dr. John Halver
16502 41 NE
Seattle WA 98155
United States

Dr. Philip Helfrich
P.O. Box 1346
Kaneohe HI 96755
United States

Dr. William Hershberger
School of Fish WH-10
University of Washington
Seattle WA 98195
United States

Dr. Gerald Heslinga
MMDC Box 359
Koror
Rep of Palah HI 96940
Caroline Islan

Dr. Hachiro Hirata
Faculty of Fisheries
Kagoshima Univ
Shimoarata 4, Kagoshima 890
Japan

Dr. Yosuke Hirono
P.O. Box 659
Guauaquil
Ecuador

Dr. Kevin Hopkins
CRSP Office of Intl Res & Dev
Oregon State University
Corvallis OR 97331
United States

Mr. U. Win Htin
Burma
c/o Bob Brick U of H
P.O. Box 1346 Coconut Island
Kaneohe HI 96744–1346
United States

Mr. Chi-Ming Huang
Tungkang Marine Laboratory
Tungkang Pingtung
R.O.C. 92804
Taiwan

Dr. David Hughes
203 Swingle Hall
Auburn University AL 36849
United States

Mr. Fritz Jaeniki
2814 Mariposa
Harlingen TX 78550
United States

Dr. Kitjar Jaiyen
National Inland Fisheries Institute
Bangkhen Bangkok 10900
Thailand

Dr. Ken Johnson
2804 Manzano
College Station TX 77840
United States

Dr. Addison Lawrence
P.O. Drawer Q
Port Aransas TX 78373
United States

Mr. Kenneth Leber
Makapuu Point
Waimanala HI 96795
United States

Ms. Concepcion Ledesma
16 Jovita Avenue
Bacolod City
Negros Occidental 6001
Philippines

Dr. Cheng-Sheng Lee
The Oceanic Institute
Makapuu Point
Waimanalo HI 96795
United States

Dr. Kendrick Lee
1071 Kalikimaka Street
Honolulu HI 96817
United States

Mr. Agustin Leong
Don Tim Development Corporation
5468 South Superhighway
Makati, Metro Manila
Philippines

Mr. Arthur Leong
Don Tim Development Corporation
5468 South Superhighway
Makati, Metro Manila
Philippines

Mr. Mark David Leslie
Casilla 10646
Guayaquil
Ecuador

Dr. Paul Liao
Kramer Chin & Mayo, Inc.
1917 First Avenue
Seattle WA 98101
United States

Dr. I-Chiu Liao
Tungkang Marine Laboratory
Tungkang Pingtung
R.O.C. 92804
Taiwan

Dr. Eliot Lieberman
Argent Laboratories
8702–152nd Ave NE
Redmond WA 98052
United States

Dr. Donald Lightner
Environmental Research Laboratory
2601 E. Airport Drive
Tucson AZ 85706
United States

Mr. Jason Lim
AA Import & Export
1000 Churucca Street
Ermita, Manila
Philippines

Dr. C. Kwei Lin
c/o AIT
G.P.O. Box 2754
Bangkok 10501
Thailand

Mr. George Lockwood
P.O. Box A
Kailua-Kona HI 96745
United States

Mr. Fidencio Loja
San Miguel Corporation
6766 Ayala Avenue
Makati, Metro Manila
Philippines

Dr. Spencer Malecha
P.O. Box 61970
Honolulu HI 96839
United States

Mr. Reuben Manik
c/o Aquatic Farms Ltd.
1164 Bishop Street Suite 1608
Honolulu HI 96813
United States

Dr. John Manzi
SC Wildlife & Marine Resources Dept.
P.O. Box 12559
Charleston SC 29412
United States

Mr. Ronald Mayo
Suite 204
108 S. Washington
Seattle WA 98104
United States

Ms. Erin McAndrew
World Aquaculture Society
341 Pleasant Hall
Baton Rouge LA 70803
United States

Dr. James McVey
12528 Knightsbridge Ct.
Rockville MD 20850
United States

Dr. Samuel Meyers
Food Science Department
Louisiana State University
Baton Rouge LA 70803
United States

Dr. Clarence McNabb
Michigan State University
East Lansing MI 48824
United States

Mr. Cornelius Mock
38 West Dansby Drive
Galveston TX 7751
United States

Dr. D.D. Moss
Fisheries Department
Auburn University
Auburn AL 36849
United States

Dr. Boedi Mranata
J1. H.R. Rasuna Said Blok B,
kav. 32–33
Jakarta 12910
Indonesia

Mr. Michael Mulvihill
Area Inc.
P.O. Box 1303
Homestead FL 33090
United States

Mr. Ram Mylvaganam
Frippak Feeds
Armstron Road
Basingstoke, Hants RG24 ONU
United Kingdom

Dr. Royden Nakamura
Biologica Sciences Department
San Luis Obispo CA 93407
United States

Dr. Colin Nash
Fisheries Devel. Food & Agric
Organization of UN
Via Del Terme Di Caracella
Rome 00100
Italy

Dr. Gary Newkirk
Dalhousic University
Halifax Nova Scotia B3H4J1
Canada

Mr. David O'Sullivan
Austasia Aquaculture Magazine
P.O. Box 1275
East Victoria Park WA 6101
Australia

Mr. Antonio Padua
San Miguel Corporation
6766 Ayala Avenue
Makati, Metro Manila
Philippines

Mr. Hector Palma
San Miguel Corporation
6766 Ayala Avenue
Makati, Metro Manila
Philippines

Mr. Siu Philippe
E.V.A.A.M. Box 11 Avatoru
Rangiroa
French Polynesia

Dr. Gary Pruder
The Oceanic Institute
Makapuu Point
Waimanalo HI 96795
United States

Mr. Raymond Rhodes
SC Wildlife and Marine Resources Dept.
P.O. Box 12559
Charleston SC 29412
United States

Dr. Robert Romaire
School of Forestry Wildlife & Fisheries
Louisiana State University
Baton Rouge LA 70803
United States

Mr. David Rouse
203 Swingle Hall
Auburn University AL 36849
United States

Mr. Eugene Rurangwa
University of Rwanda
Butare, Rwanda
Africa

Dr. M. Sakthiviel
MPEDA, Inda
c/o Bob Brick U of H
P.O. Box 1346 Coconut Island
Kaneohe HI 96744–1346
United States

Dr. Paul Sandifer
SC Wildlife & Marine Resources Dept.
P.O. Box 12559
Charleston SC 29412
United States

Dr. Edward Scura
1164 Bishop Street
Suite 1608
Honolulu HI 96734
United States

Dr. Wayne K. Seim
Oregon State University
Corvallis OR 97331
United States

Dr. Yung Shang
Dept. of Ag/Resource Economics
University of Hawaii
3050 Maile Wy Gilmore Hall 112
Honolulu HI 96822
United States

Dr. Kunihiko Shigueno
2631 Yoshinocho
Kagoshima City 892
Japan

Dr. Robert Shleser
P.O. Box 560
Waimanalo HI 96795
United States

Mr. Somsuk Singholka
Aquafauna Bio-Marine
P.O. Box 5
Hawthorne CA 90250
United States

Mr. Julian Smets
Artemia Systems N.V.
F. Laurentplein 29
B-9000 Gent

Dr. Theodore Smith
SC Wildlife & Marine Resources Dept,
P.O. Box 12559
Charleston SC 29412
United States

Dr. P. Sorgeloos
Artemia Ref Center
Rozier 44 9000 Gment
Belgium

Dr. Robert Stickney
School of Fisheries WH-10
University of Washington
Seattle WA 98195
United States

Mr. Alan Stockwell
#600 222 Somerset St. W.
Ottawa, Ontario K2P 2G3
Canada

Mr. Mahmod Tahir
Ko-Nelayan, Locked Bag 150
88999 K.K.
Kota Kinabalu, Sabah
Malaysia

Mr. George Tan
AA Import & Export
1000 Churucca St.
Ermita, Manila
Philippines

Dr. Hideyuki Tanaka
FAO Aquaculture Project
c/o UNDP Private Mail Bag
Suva
Fiji Islands

Dr. David Teichert-Coddington
Auburn University AL 36849
United States

Dr. Sujint Thammasart
Thai Prawn Culture Center Ltd.
36 Soi Yenchit, Chand Rd.
Bangkok 10120
Thailand

Dr. Ron Thune
Louisiana State University
Baton Rouge LA 70810
United States

Mr. Chu Chiun Tien
Nan Rong Fishing Machinery Co.
75–10, I-Chou Li,
Yiang Hsue Cheng
Tainan Hsiang, R.O.C.
Taiwan

Mr. Amadeo Timbol
Kauai Community College
University of Hawaii
3–1901 Kaumualii Hwy
Lihue HI 96766
United States

Dr. Richard Tubb
Oregon State University
Corvallis OR 97331
United States

Ms. Isidra Tuburan
15 Tantiado St.
Tigbauan, Iloilo
Philippines

Ms. Deborah Turnbull
#600–222 Somerset St. W.
Ottawa, Ontario K2P 2G3
Canada

Mr. Vanich Varikul
Department of Fisheries
Ministry of Agriculture & Cooperatives
Rajadamnern Avenue, Bangkok
Thailand

Ms. Karen Veverica
Department of Fisheries OSU
Corvallis OR 97331
United States

Mr. Untung Wahyono
Department of Fisheries - Indonesia
c/o Bob Brick U of H
P.O. Box 1346 Coconut Island
Kaneohe HI 96744–1346
United States

Dr. Richard Weisburd
Department of Oceanography
1000 Pope Rd
Honolulu HI 96822
United States

Mr. Ronald Young
Don Tim Development Corporation
5468 South Superhighway
Makati, Metro Manila
Philippines

Mr. Michael Yunker
1164 Bishop Street
Suite 1608
Honolulu HI 96813
United States

Dr. Felix Yusay
Sugarland Hotel
Bacolod City
Negros Occidental
Philippines

Mr. Edgardo Zaragoza
2280 Pasong Tamo Extension
Makati, Metro Manila
Philippines

APPENDIX B
LIST OF EXHIBITORS

ADPI ENTERPRISES, INC.
3621 B Street
Philadephia, PA 19134
(215) 425–8866

AERATION INDUSTRIES, INC.
1107 Hazeltine Blvd.
Chaska, MN 55318
(612) 448–6789

ALMA-FEEDS
Postbox 1345
D-8960 Kempten/Allgaeu FRG
0831-70-3313

AQUACULTURE INTERNATIONAL
Box 202–999 Canada Place
Vancouver, B.C. V6C 3C1
(604) 681–1988

AQUACULTURE MAGAZINE
P.O. Box 2329
Asheville, NC 28802
(704) 254–7334

AQUAFAUNA BIO-MARINE, INC.
P.O. Box 5
Hawthorne, CA 90250
(213) 973-52-75

AQUATESS (CANADA) LTD.
1350 East Kent Ave.
Vancouver, B.C.
(604) 327–6327

AQUATIC ECO SYSTEMS, INC.
P.O. Box 1446
Apopka, FL 32704
(305) 886–3939

AREA, INC.
P.O. Box 1303
Homestead, FL 33090
(305) 248–4205

ARGENT LABORATORIES
8702-152nd Ave. NE
Redmond, WA 98052
(206) 885–3777

ARTEMIA SYSTEMS N.V.
F. Laurentplein 29
B-9000 Gent, Belgium
(009) 123–9552

ATEC, INC.
877 N. 8th W
Riverton, WY 82501
(307) 856–9271

AUSTASIA AQUACULTURE MAGAZINE
P.O. Box 1275
East Victoria Park W.A. 6101
Australia, 61-9-361-6600

BAYLAND FISHERIES CORPORATION
P.O. Box 850
Panacea, FL 32346
(904) 984–0082

BIOMED RESEARCH LABS, INC.
1720 130th Ave. N.E.
Pellevue, WA 98005
(206) 882–0448

ELSEVIER SCIENCE PUBLISHING CO., INC.
52 Vanderbilt Ave.
New York, NY 10017
(212) 916–1013

THE ESTATE OF JAMES CAMPBELL
828 Fort St. Mall, Suite 500
Honolulu, HI 96813
(808) 536–1961

FLEX-A-LITE CONSOLIDATED
4540 South Adams
Tacoma, WA 98409
(206) 475–5772

FRIGID UNITS, INC.
3214 Sylvania Ave.
Toledo, OH 43613
(419) 474–6971

FRIPPAK FEEDS
Armstrong Road
Basingstoke, Hants, RG24 ONU England
0256 46–0414

FRITZ AQUACULTURE
P.O. Box Drawer 17040
Dallas, TX 75217
(214) 285–5471

HACH COMPANY
P.O. Box 389
Loveland, CO 80539
(303) 669–3050

HARRINGTON MEDI
P.O. Box 2306
Twin Falls, ID 83303
(208) 734–2884

HYDROLAB CORPORATION
P.O. Box 50116
Austin, TX 78763
(512) 255–8841

IMPORT ASSOCIATES
P.O. Box 16350
San Francisco, CA 94116
(415) 591–2200

INDUSTRIAL PLASTICS, INC.
740 South 28th Street
Washougal, WA 98607
(206) 835–2129

INOTEC INTERNATIONAL
18 Avenue De La Rivette
27400 Louviers, France
(333) 240–2711

INTERNET INCORPORATED
2730 Nevada Avenue North
Minneapolis, MN 55427
(612) 541–9690

ISLAND SCIENCE
Box 564
Novato, CA 94948
(415) 898–1422

LIPPERT INTERNATIONAL/STERLING SYSTEMS
P.O. Box 8766
Jacksonville, FL 32239
(904) 724–3400

MARIQUEST, INC.
18 Corporate Plaza
Newport Beach, CA 92660
(714) 759–5500

MARYLAND DEPT. OF AGRICULTURE
50 Harry S. Truman Parkway
Annapolis, MD 21410
(301) 841–5770

MFDIPHARM U.S.A.
10215 Dennis Drive
Des Moines, IO 50322
(515) 270–6851

MET-PRO CORPORATION
160 Cassell Road, Box 144
Harleysville, PA 19438
(215) 723–6751

MUREX AQUA FOODS, INC.
#207–20701 Hwy 10
Langley, B.C. V3A 5E8 Canada
(604) 530–7217

NAN RONG FISHING MACHINERY CO., LTD.
75–10, I-Chou Li, Yiang Hsuei Cheng,
Tainan Hsiang, Taiwan, R.O.C,
02–3932204

NIPPAI SHRIMP FEED INC.
3–9 Moriya-Cho Kanagawa-Ku
Yokohama, Japan (221)

NORTH STAR ICE EQUIPMENT CO.
P.O. Box 70668/4511 Shilshole Ave NW
Seattle, WA 98107
(206) 784–4500

NOVALEK INC.
2242 Davis Court
Hayward, CA 94545
(415) 782–4058

OCEAN STAR INTERNATIONAL, INC.
P.O. Box 643
Snowville, VT 84336
(801) 872–8217

RANGEN, INC.
P.O. Box 706
Buhl, ID 83316
(208) 543–6421

RED EWALD INC.
P.O. Box 519 Hwy 181 South
Karnes City, TX 78118
(512) 780–3304

ROWLAND FIBERGLASS, INC.
P.O. Box 971
Ingleside, TX 78362
(512) 776–7753

ROYCE INSTRUMENT COMPANY
4301 Poche Court West
New Orleans, LA 70129
(504) 254–3500

RYAN INSTRUMENTS
P.O. Box 599
Redmond, WA 98073
(206) 883–7926

SAN FRANCISCO BAY BRAND, INC.
8239 Enterprise Dr.
Newark, CA 94560
(415) 792–7200

SANDERS BRINE SHRIMP CO.
3850 So. 540 W
Ogden, UT 84405
(801) 393–5027

SEA FARMS INC.
29 Congress Street
Salem, MA 01970
(617) 745–4569

SORT-RITE INTERNATIONAL, INC.
P.O. Box 1805
Harlingen, TX 78551
(512) 423–2427

STATE OF HAWAII
Aquaculture Development Program
335 Merchant St. Suite 359
Honolulu, HI 96813
(808) 548–5495

SWEENEY ENTERPRISES, INC.
Rt 2 Box 2452
Boerne, TX 78006
(512) 537–4175

UNISYN OF HAWAII
P.O. Box 12520
Seattle, WA 98111
(206) 622–6767

WATER MANAGEMENT INC.
Box 4747
Englewood, CO 80155
(303) 792–5777

WENGER INTERNATIONAL, INC.
One Crown Ctr. 2400 Pershing Rd #510
Kansas City, MO 64108
(816) 221-5084

YSI INCORPORATED
P.O. Box 279
YellowSprings, OH 45387
(513) 767–7241

APPENDIX C
ABSTRACTS OF SELECTED PAPERS OF INTEREST
TO PHILIPPINE AND ASIAN AQUACULTURE

1.     RESPONSE TO PENAEUS INDICUS POSTLARVAE TO VARIOUS FEEDS.

Veronica R. Alava*, Aquaculture Department, Southeast
Asian Fisheries Development Center, P.O. Box 256
Iloilo City, Philippines.

Penaeus indicus postlarvae 5 (9 mm mean total length, 3 mg mean wet body weight) were fed with five dry artificial diets (commercial feed A, B, C, experimental diets PL-P and 2S) and a control (fish muscle). The shrimps were reared under the following conditions:feeding level, 30% of the body weight/day (dry matter basis); feeding frequency, three times a day; particle size of diets, 425 urn; stocking density, 200 individuals/30 liters of water; salinity, 32–34 ppt; water temperature 28–29°C. On day 30, shrimps attained mean total lengths of 13 to 22 mm. The mean wet body weight of shrimps fed PL-P (57 mg) was significantly higher (P < 0.01) than those of shrimps fed Diets A, B, 2S and fish muscle but not with those red Diet C. The survival rate of shrimps fed PL-P was the highest (92%), significantly higher (P<0.01) than those fed Diet B (69%) and fish muscle (14%). Results showed the feasibility of rearing P. indicus postlarvae with PL-P formulated diet,

* Presenting author

2.     A TENTATIVE YIELD-DENSITY MODEL FOR MACROBRACHIUM ROSENBERGII REARED UNDER DISCONTINUOUS CULTURE CONDITIONS.

AQUACOP and Loic Antoine, IFREMER, Centre Oceanologique du Pacifique, BP 7 004 Taravao, Tahiti, French Polynesia.

A simple model has been imagined to give the evolution of the individual mean weight (g) and yield (t/ha/year) with initial densities varying from 1 to 21 individuals/m². The mean initial weight is 1 g, supposing an initial rearing from PL to 1 g not included in the model.

Data for growth and mortality have been found AQUACOP experiments in Tahiti, IFREMER experiments in Martinique and from literature. The model can be used as a forecasting tool for farmers rearing Macrobrachium under discon-tinuous culture system.

3.     A BIOTECHNICAL MICROCOMPUTERIZED MANAGEMENT PROGRAM FOR A TROPICAL SHRIMP FARM (MACROBRACHIUM OR PENAEIDS).

AQUACOP, Regis, F. Bador and Jean-Nicolas R. Bazin IFREMER Centre Oceanologique de Pacifique, BP 7 004 Taravao, Tahiti, French Polynesia.

Operating a commercial shrimp farm implies the integration of various and biological, technical and financial data. A microcomputerized program can greatly alleviate such a management. The proposed program concerns as a Macrobrachium or Penaeid shrimp farm working under a discontinuous culture system. The data management system used is Knowledge-Man (2.01 Version) working through MS-DOS. Survival and feeding rates, estimated from IFREMER/COP results, are entered as biological hypothesis and can be adjusted to peculiar local conditions.

At pond scale, physicochemical parameters are recorded daily, whereas fertilizer and food quantities, sampling data and harvest results are entered every two weeks. At farm scale, purchases and sales are entered every two weeks.

From the latest data input, the farmer is proposed an estimation of the growing biomass and the daily rations for each pond and for the next two weeks. The farmer can modify these proposed figures according to special observations or events.

A biotechnical synthesis for each grow-out pond, along with a cash-flow and book-keeping summary are printed once a month. An end-of-rearing analysis sheet is printed after the final harvest, and presents all the calculated results necessary to estimate the performance of the grow-out.

This program will be improved from experiences in farms which use it. A special version for Macrobrachium continuous culture farms will be soon realized.

4.     EFFECTS OF DISSOLVED OXYGEN CONCENTRATION ON SURVIVAL AND GROWTH OF PENAEUS VANNAMEI AND PENAEUS STYLIROSTRIS.

AQUACOP, Edouard Bedier and Claude Soyez, IFREMER Centre Oceanologique du Pacifique, BP 7 004 Taravao Tahiti, French Polynesia.

The water dissolved oxygen concentration (DO; is one of the most important parameters of pond management. If lethal values of DO are fairly well known, there are few data on long term effects of sub-lethal values on survival and growth of peuaeid shrimps. A profitable management of ponds (water renewal, use of aeration devices, etc.) largely depends on these data.

A DO continuous monitoring system allowed us to submit Penaeus vannamei and P. stylirostris individually tagged to the following conditions:saturation of DO as reference, continuous level of 3 ppm, continuous level of. 1.5 ppm and diurnal like 6 h-18 h cycle at respectively. 1.5 ppm and saturation.

No significant survival and growth difference occurred for P. vannamei sub-mitted to a continuous concentration of 3 ppm, but mortality occurred as early as the fourth day at a continuous concentration of. 1.5 ppm. Survival and growth of P. vannamei and P. stylirostris were significantly lowered under diurnal-like cycle condition; the molting cycle of these shrimps was modified in comparison to the cycle of those maintained at a constant level of 3 ppm and higher.

As a consequence, it is very likely that in grow-out conditions, an important decrease of the dissolved oxygen concentration during the night time affects the growth of shrimps even if diurnal conditions are adequate.

5.     MAINTENANCE OF WATER QUALITY BY BACTERIAL SYSTEMS IN INTENSIVE TROPICAL PENAEID SHRIMP CULTURE:PRELIMINARY RESULTS.

AQUACOP and Edouardo Bedier, IFREMER, Centre Oceanologique du Pacifique, BP 7 004 Taravao, Tahiti, French Polynesia. Micheline Bianchi, CNRS ER223, Campus de Luminy Case 907 70 route Leon Lachamp 13 288 Marseille Cedex 9, France.

The “Centre Oceanologique du Pacifique” in Tahiti has investigated for several years the tropical penaeid shrimp intensive culture. Extrapolated yields up to 27 metric tons/ha/year have been obtained in aerated ponds with low water renewal rates. Considering the high biomass reached in these ponds, the maintenance of a suitable water quality constitutes a critical point, mainly for the elimination of nitrogenous wastes; the development in the pond water itself of planktonic and bacterial populations, insures the mineralization of organic matter and the nitrification of wastes.

The experiments conducted in 1 and 10 cubic meter circular tanks showed that the nitrification process occurred systematically and that only the duration of each step of the process was influenced by initial biomass and water quality. The establishment of this process was studied for 200, 400, 560, 600 and 800 g/m² biomasses, and the respective ammonification and ammonium oxidation rates (Kl and K2) were calculated. Reference tanks without animals fed at the same rate as the ones with a shrimp biomass exhibited the same ammonification rate, which suggests that this process is independent from animal biomass and must be related to food only.

With a biomass of 560 g/m², and with water initially inoculated from an intensive grow-out pond, ammonia disappeared within 30 days and nitrite within 50 days; counts of total bacteria fluctuated around 1 million/ml, and those of heterotrophic bacteria around 10,000/ml. Evolution of microorganism populations (bacteria and predatory protozoa) was studied.

The results presented in this paper are a first step towards a better understanding of this particular kind of intensive culture system, and towards its modelization.

6.     PRELIMINARY NUTRITIONAL STUDIES OF SEABASS LATES CALCARIFER (BLOCH):PROTEIN AND LIPIN REQUIREMENTS.

AQUACOP, Gerard Cuzon and Jacques Fuchs, IFREMER Centre Oceanologique du Pacifique,, BP 7 004 Taravao Tahiti, French Polynesia.

Some dietary requirements of seabass fry imported from Singapore were studied at the Centre Oceanologique du Pacifique.

In a first experiment, four diets ranging from 35 to 55% protein content mainly from Norway fish meal were compared to a control diet at 52% protein including fish meal plus fish protein concentrate. Protein/energy ratio was fixed around 140 mg protein/kcal. Juveniles weighing 35 grams were randomized and distributed at 35 to 38 fish per tank in two replicates. The preliminary results from the four experimental diets revealed an optimum of protein requirement ranging from 45 to 55%. The highest growth rate was obtain with the 52% protein reference diet, a result that can be related to the protein quality of this formula.

In a second experiment, three diets at 6, 10 and 14% lipid and 52% protein content were allocated in three blocks of 21 fish per tank (average initial weight:20, 25 and 30 grams). No significant difference of growth and survival rates were recorded. The sparing action of the dietary lipid was not proved in the studied range of 6 to 14% of the diet. From these results, it can be estimated that the digestible energy requirement could be reduced around 6.7 kcal per gram of diet for Seabass juveniles. The formulation of a commercial fish feed for Seabass is still under progress, studying energy-ratio and protein source quality.

7.     MONITORING OF DISSOLVED OXYGEN LEVEL IN PENAEID INTENSIVE GROW-OUT PONDS.

AQUACOP and Alan Febvre, IFREMER, Centre Oceanologique du Pacifique, BP 7 004, Taravao, Tahiti, French Polynesia.

Intensive grow-out ponds of Penaeid shrimps undergo great variations of dissolved oxygen (DO) concentration related to changes in culture conditions (phytoplanktbn density biomass, water renewal, bottom condition, ...). Culture methods are briefly discussed, considering mainly their impact on DO level, which was monitored continuously over the rearing period. The selection of oxygen transfer systems, and the optimization of their use are particularly studied.

An analysis procedure of the DO concentration variations in pond water is proposed, with respect to the usually recorded physicochemical and biological parameters. This procedure is utilized to evaluate the performances of the different aeration devices in conditions close to the intensive culture ones.

The changes and incidents observed during the grow-out period are correlated to the DO concentration variations; this enables to classify these changes, and select the appropriate measures to recover adequate culture conditions. This study further allows one to make an objective evaluation of the commonly used intensive pond management strategies, and to propose new types of interventions.

8.     REPRODUCTION OF GROUPER EPINEPHELUS MICRODON IN FRENCH POLYNESIA. NATURAL CYCLE CHARACTERISTICS AND FIRST RESULTS IN CAPTIVITY.

AQUACOP, Jacques Fuchs and Laurent Debas, IFREMER, Centre Oceanologique du Pacifique, BP 7 004 Taravao, Tahiti, French Polynesia. Bernard Jalabert, INRA, Laboratoire de Physiologie des Poissons, Campus de Beaulieu, 35 042 Rennes Cedex, France. Eric Morize, ORSTOM BP 529 Papeete, Tahiti, French Polynesia.

Little basic information is available on Epinephelus microdon, a candi-date species for aquaculture in Erench Polynesia. Researches were therefore, conducted in 1985–1986 on the reproduction cycle and the sexual dimorphism of this species in the wild and its propagation in captivity.

Regular collection of fish in Tikehau atoll (Tuamotu Islands) clearly showed the seasonal characteristic of the reproduction in the wild, with a maximum sexual activity in March, although some mature individuals were observed all over the year. First maturations were noticed on 0.4–0.5 kg mean weight fish, and the sex reversal of this protandric hermaphroditics species appeared from 1 kg on. Studies to identify sex by morphometric variations were not statistically conclusive (24% error) when compared to the mean weight criteria (26% error).

In captivity, the grouper has been observed to spawn naturally, from November to April, according to lunar cycle, with a peak of activity in February. Nineteen natural spawnings and 16 million eggs (860 jim diameter; 95% fertilization rate) were obtained in 1986, each female deposing 0.8 to 1 million eggs per kg. In 1985 comparative studies were carried out using hormone injections (LHRH and HCG):few females correctly responded to the treatment, but produced good quality eggs.

Preliminary larval rearing trials showed a peak of mortality on days 4–5 corresponding to the first feeding period, and on days 10–15, with a total mortality after day 20. An inadequate food sequency was suspected to be the major.reason for these strong mortalities. Further research has to be conducted both on the control of maturation and the larval rearing of this promising species for aquaculture.

9.     A COMPUTER MANAGEMENT INFORMATION SYSTEM FOR A COMMERCIAL SHRIMP CULTURE OPERATION.

Sidney B. Ashmore*, Amorient Aquafarm, Inc.
P.O. Box 131, Kahuku, Hawaii 96731 USA.

A menu driven computer management information system was set up at the Amorient Aquafarm, Inc. Kahuku operation. The system stores data and generates weekly and monthly production reports for both the hatchery and farm operations. The system consists of an IBM PC “AT class” clone that runs at 4.77 or 8 mhz with DOS 3.1 and 760 Kb RAM. A 45 Mb fixed disk, 360 Kb floppy and a 20 Mb tape back-up provide ample disk space. A battery back-up and line conditioner are on line to collectively supply enough power to save all open files and bring the system down during a blackout and prevent any damaging voltage spikes or surges.

10.  NAUPLII PRODUCTION RESULTS FROM A COMMERCIAL PENAEUS VANNAMEI MATURATION FACILITY IN HAWAII.

Sidney B. Ashmore*, Amorient Aquafarm, Inc.
P.O. Box 131, Kahuku, Hawaii 96731 U.S.A.

Amorient Aquafarm, Inc., in Kahuku, Hawaii constructed and stocked three 4.6 meter diameter maturation tanks in September of 1986. Two F2 and one F3 Penaeus vannamei generations were stocked at 5.5 broodstocks/m². The F3 gene-ration was stocked at a 1.6:1 female:male ratio while the F2 generations were stocked at 1:1 and 1.6:1 female:male ratios. Mean size at stocking was 49 g, 40 g and 37 g for the F3, F2 1:1 ratio and F2 1.6:1 ratio populations, respec-tively. Approximately two months elapsed before the three populations reached average monthly nauplii production levels for the 7.5 month production period. Total nauplii production from September 1986 to the middle of May 1987 was 27.4 million, 19.4 million and 13.9 million for the F3, F2 (1:1 ratio) and F2 (1.6:1 ratio) populations, respectively. The F3 population recorded 417 fertile spawns while the F2 populations recorded 313 (1:1 ratio) and 263 (1.6:1 ratio) fertile spawns. Differences in average nauplii per spawn and percent hatch rate were less dramatic between the three tanks, ranging from 53K to 66K nauplii per spawn while the average percent hatch rate ranged from 39% to 46%. Individual spawning histories of female broodstock from all three maturation populations were recorded. The results suggest that manipulation of stocking ratios and monitoring of individual female performance may lead to a maximization of nauplii produced under the present system.

11.  AMMONIA-AMMONIUM NITROGEN UPTAKE BY CHAETOCEROS GRACILIS WITH APPLICATIONS IN SHRIMP MARICULTURE.

Daniel J. Avery, Texas A & M University Galveston Galveston, TX 77553. David V. Aldrich, Department of Marine Biology, Texas A & M University Galveston Galveston, Texas 77551.

Water quality control is of major importance in high density shrimp rearingimp operations. The microalgae Chaetoceros gracilis, which is a common larval shrfood source, was tested for its ability to utilize ammonia-ammonium nitrogen (NH₃/NH₄-N).

Each of three uniform log phase cultures of Chaetoceros gracilis was divided into three treatments per experiment; 1) culture medium with added NH3/NH4-N and without Chaetoceros, 2) culture medium with added NH3/NH4-N and with Chaetoceros, 3) culture medium with added NH₃/NH₄-N and with Chaetoceros. Two light intensities (106.1 and 3.2uE) were also tested to simulate different environmental conditions. At the higher level the original amount of NH₃/NH₄-N (.375 mg/l) was reduced by approximately 69% after one hour, and by about 99% after three hours. Reductions of slightly less magnitude were observed at the lower light intensity (68% and 90Z, respectively). This data indicates that Chaetoceros gracilis reduces NH₃/NH₄-N levels at a rapid rate under experimental conditions, and may be useful in this role in shrimp hatchery operations,

12.  SELECTION INDEX FOR COMPARATIVE EVALUATION OF OREOCHROMIS NILOTICUS STRAINS DURING EARLY DEVELOPMENT.

Zubaida U. Basiao*, Southeast Asian Fisheries Development Center, Binangonan Freshwater Biology Station, Binangonan Rizal, Philippines. Roger W. Doyle, Department of Biology Dalhousie University, Halifax, NS B3H 4JI, Canada.

Several strains of Oreochromis niloticus, O. mossambicus and their hybrids occur in the Philippines and others are likely to be introduced or developed locally in the near future. There is a tendency towards genetic deterioration of strains under commercial cultivation owing to inbreeding, population bottlenecks, uncontrolled hybridization and reverse selection.

The objective of the project is to develop an “index” for between-strain monitoring, comparison and selection that is usable at the young juvenile stage. The methodology is to measure variables relating to early growth and stress resistance, and associate them, (by multivariate techniques) with the grow-out performance and quality of the same strains in commercial environments.

The paper reports on 3 aspects of the work on young fish:1) the use of a control population of “red” genotypes to provide internal statistical control over among replicate variability in growth; 2) the use of size-specific growth estimators to reduce non-genetic maternal effects; and 3) the use of micro-developmental abnormalities in scale morphology to measure stress responses individually and non-destructively, without resotting to LD-50 or similar popu-lation-level responses. Used together, the procedures reduce environmental error while greatly increasing the degrees of freedom available for statistical hypothesis testing in experiments of modest size.

(Note:For oral presentation at the 1988 meeting of the World Aquaculture Society).

13.  SELECTED SECTIONS FROM A HANDBOOK OF NORMAL PENAEID SHRIMP HISTOLOGY.

T.A. Bell*, D.V. Lightner and W.C. Randall, University of Arizona Environmental Research Laboratory 2601 E. Airport Drive, Tucson, AZ 85706.

The presented poster depicts excerpts from an upcoming publication. The excerpts illustrate selected micrographs from several representative chapters. In addition to the micrographs, the poster contains a pictorial representation of the macroscopic location of the selected micrographs.

The forthcoming publication will be a definitive handbook of B&W, and color light micrographs, characterizing the complete histology of a typical penaeid shrimp. The handbook will include limited text, consisting of chapters covering:techniques, nomenclature, bibliography and index. The majority of the handbook is composed of micrographic plates with facing pages of expanded captions. The micrographs are arranged in chapters, each of which describes the normal histology of a particular anatomical system. Color micrographs supplement the B&W in those sections where relevant information can only be visualized with tissue-specific histochemical stains.

14.  MICROBIAL PRODUCTION OF NUTRITIONAL PROTEIN FOR AQUACULTURE SYSTEMS.

J.A. Bender, I. Ekpo, Y. Vatcharapuarn and E.R. Archibold Department of Biology, Morehouse College, Atlanta, GA 30314.

The objective of this research was to develop a low-cost, high quality protein for application in aquaculture systems. Since the intent was to develop a method which is easily transferred to developing countries, only available waste biomass and low-technology processes were used. Grass clippings were anaerobically digested by a simple silaging process, then used as a feed-stock for nitrogen fixing, asymbiotic bacteria and cyanobacteria in simulated labora-tory ponds. Protein levels increased from 10–15% in the silage to 20–30% in the final microbial biomass in 7–10 days. The microbes attached to the silage forming a buoyant gelatinous mat which was easily harvested by raking the surface of the pond. Outside ponds in Santiago, Dominican Republic, showed productivity similar but somewhat lower in protein to that of the simulated laboratory ponds. Results from digestion studies with T. nilotica and H. molitrix (Silver carp) indicated that the silage/microbe product competed favorably with commercial cat-fish feed in percent digestibility.

15.  ENHANCED GROWTH OF THE NEMATODE, PANAGRELLUS REDIVIVUS. BY FATTY ACID MANIPULATION AND THE EFFECT OF THAT MANIPULATION ON THE GROWTH OF LARVAL PENAEUS VANNAMEI.

James M. Biedenbach*, Linda L. Smith and Addison L. Lawrence Shrimp Mariculture Project, Texas Agricultural Experiment Station, Texas, A&M University System, P.O. Drawer Q Port Aransas, TX 78373.

Corn oil, menhaden oil and yeast were added in varying combinations to culture media of Paragrellus redivivus to effect a change in growth and fatty acid content. The addition of corn oil, menhaden oil or yeast to cultures increased nematode growth by 13%, 32% and 36%, respectively over standard media. Combinations of corn oil + yeast and menhaden oil + yeast increased nematode growth 68% and 63%, respectively.

Fatty acid content was altered in nematodes cultured on media containing oils. Significant increases in fatty acids 18:0 and 18:2 were observed in those nematodes cultured in the presence of corn oil, while significant increases in fatty acids 14:0, 16:0, 16:1, 20:5 and 22:6 were found in those nematode cultured on media containing menhaden oil.

Experiments with Penaeus vannamei larvae fed standard, yeast modified, corn yeast modified, and menhaden-yeast modified nematodes resulted in no significant differences in survival and metamorphosis between any of the nematode-algae fed treatments and the standard algae Artemia control. Significant differences in growth (dry weight) were observed between larvae fed nematodes modified by yeast or menhaden-yeast and those fed nematodes modified with corn oil suggesting a lack of essential fatty acids in the corn oil modified nematodes. Although nematodes cultured with menhaden oil accumulated high amounts of highly unsaturated fatty acids, these levels did not improve growth of P. vannamei over unmodified nematode controls.

16.  IMPROVED ACUTE TOXICITY TESTS WITH PENAEID POSTLARVAE.

Patrick W. Borthwick, U.S. Environmental Protection Agency, Environmental Research Labotarory, Gulf Breeze FL 32561. John E. Bente and Christopher D. Howell Continental Fisheries Ltd., 4104 West 23rd Street Panama City, FL 32405.

Contamination of water sources for shrimp farming facilities may reduce the quality of the marketable shrimp. A simple bioassay and toxicity test for water quality was developed which uses early postlarvae of penaeid shrimp. This test procedure is based on existing static acute toxicity tests for mysiads. Seven day old postlarvae (PL-7) of penaeid shrimp are recommended for testing because PL 14-21-28 jumped out of the test media. Tests with PL-7 gave acceptable survival and concentration/effect relationships. Sensitivity to toxic compounds was similar to that of mysids and other estuarine crustaceans. The added advantage of the penaeid shrimp test is that it directly relates to industry needs. Data are presented that show sensitivity of Penaeus vannamei in comparison to mysis and other crustaceans. Recommendations are made for incorporation of the penaeid test as a screening method for adequate water quality in shrimp culture.

17.  SMALL SCALE COMMERCIAL SHRIMP FARMING IN THE CARIBBEAN-FACT OR FANTASY?

Nigel L. Bowers, Leeward Islands Shrimp Company Ltd.
P.O. Box 284, St. Kitts, West Indies.

Profitable commercial shrimp farming on any scale in the Caribbean has yet to become a reality. The purpose of this paper is to discuss some of the major reasons for this failure and to demonstrate ways in which many of these obstacles can be overcome. The paper focuses primarily on the systems developed over the last four years by Leeward Islands Shrimp Company Ltd., a small totally integrated commercial farm on St. Kitts. The results of three years of commercial maturation, hatchery and grow-out operations are discussed in terms of maximizing system efficiency under sub-optimal culture conditions.

Particular attention is given to pond production data for small ponds at high salinities (greater than 40 ppt) and the effects on growth rates using post larvae from pond raised broodstock and from wild caught ones. Preliminary observations suggest that the FI generation from shrimp raised in high salinity ponds exhibits superior grow-out performance to either their parents or their offspring.

18.  EVALUATION OF SURFACE AERATORS FOR USE IN AQUACULTURE PONDS.

Claude E. Boyd, Department of Fisheries and Allied Aquaculture, Auburn University, Alabama 36849 USA.

Thirty-two aerators representing all basic types of surface aerators were tested for standard oxygen transfer rate (SOTR) and standard aeration efficiency (SAE). Electric paddle wheel aerators were more efficient than other types of aerators in transferring oxygen. Specifications for construction of electric paddle wheel aerators that have SAE values of around 4.5 lb 0₂/hp.hr under standard conditions are presented. Methods for estimating oxygen transfer under actual pond conditions and calculating cost of operation are provided. Paddle wheel aerators also may be driven by diesel or gasoline engines. Strategies for optimum use of aeration in ponds is discussed and supported with results of recent studies.

19.  DEVELOPMENTS IN GIANT CLAM MARICULTURE IN AUSTRALIA.

R.D. Braley, Zoology Department, James Cook University Townsville, Queensland 4811, Australia.

Studies of methods for farming giant clams have resulted from the awareness of the rapid decline of natural populations from overfishing in the Pacific region and the clams' intrinsic peculiarity of autotrophy, which obviates the need for feeding. An international research program funded by the Australian Centre for International Agricultural Research (ACIAR) is based at James Cook University and Orpheus Island with affiliated programs in the Philippines, Fiji and Papua New Guinea. There is also a high level of communication between this program and the Giant Clam program at the MMDC in Palau. Contrary to the culture of Tridacna derasa in Palau, the ACIAR program has focused on the largest and fastest growing species, Tridacna gigas, with less emphasis on Hippopus hippopus and Tridacna squamosa. Selection of broodstock utilizing a biopsy technique and spawning induction by serotonin are used routinely. The larvae have been reared successfully using modified temperate intensive bivalve hatchery techniques. Semi-intensive methods of culture have yielded about 10-fold lower survival from eggs to 5 month old seed than intensive methods. Nevertheless, mortality of post-settled to metamophosing larvae remains high and requires further research. In a comparison of four positions of holding juvenile clams during the ocean-nursery phase (floating, subtidal rack, benthic and intertidal benthic), the intertidal position resulted in high survival, near maximum growth rates, and tolerance of clams to considerable periods of intertidal exposure without negative effects. Protected fringing reefs resulted in better growth than exposed fringing reefs. Cultute in the intertidal zone is more economical in construction and maintenance. Large-scale systems using 30 m × 1 m × 0.2 m 'Lines' (rectangular boxes) and mesh 'Covers' directly over the clams on the natural substrate are now being tested for ocean nursery of Tridacna gigas. Private enterprise has shown an interest in T. gigas farming in North Queensland with the establishment of two operations near Cairns using semi-intensive land-based and extensive ocean-based larval and seed culture.

20.  INFLUENCE OF DIETARY FATTY ACIDS ON REPRODUCTION OF PENAEUS STYLIROSTRIS

William A. Bray* and Addison L. Lawrence, Shrimp Maricultural Experiment Station, Texas A&M University System, 4301 Waldron Road, Corpus Christi, TX 78418.

Fatty acid profiles of gonad, hepatopancreas and muscle tissues of female Penaeus stylirostris were compared after animals were fed various diets for 90 days. Treatments consisted of an all fresh-frozen diet (squid, bloodworms, shrimp and brine shrimp in a 4:2:2:1 ratio) and three combination diets of 40% squid and 60% prepared dry feed. The combination diets were similar in composition, but varied in total dietary lipid.

Fatty acid composition of tissues in the combination diet treatments differed strongly from the fresh-frozen diet treatment. Treatments containing 50% prepared diet components showed increased C14 and C16 fatty acids, and decreased levels were increased in combination diet treatments 200–800% over the tissue levels found in the fresh-frozen diet treatments. Gonad tissue long chain fatty acid levels in the fresh-frozen treatment were most similar to those of control females (wild matured), with the following levels (mean± SD):18:2, 1.23±0.55%; 20:4, 2.33 ± 0.45%; 20:5, 9,33 ± 0,9%; 22:6, 14.83 ± 1.50%. Reproductive performance, evaluated by number of eggs per spawn, percent hatch, number of nauplii per spawn, and protozoea 1 length, was significantly better in the all fresh-frozen diet.

21.  SUCCESSFUL REPRODUCTION OF PENAEUS MONODON AETER, CULTURE UNDER HYPERSALINE CONDITIONS,

William A. Bray*, Addison L, Lawrence and Joanna R. Leung-Trujillo, Shrimp Mariculture Project, Texas Agricultural Experiment Station, Texas A&M University System, 4301 Waldron Road, Corpus Christi, TX 78418.

Penaeus monodon postlarvae (Malaysian origin, N = 100) were cultured to adulthood, with the final six months of grow-out under salinity levels ranging from 42–52 ppt. Upon transfer from a hypersaline earthen pond, broodstock were olive drab in appearance an exhibited no ovarian development. Adults were acclimated to oceanic salinity (35 ppt) in a laboratory recirculating system and-ablated after two days. For two weeks, all shed exoskeletons of females were dissected to determine presence of spermatophores. Results Of dissections and light microscope evaluation of sperm indicated all females (N = 20) had mated under the hypersaline pond conditions prior to placement in the labora-tory. Sperm appeared morphologically normal.

After three to four weeks of exposure to oceanic salinity in laboratory conditions, strong brown and black markings on the exoskeleton were exhibited by the broodstock, and ovarian development followed. The first mature female was isolated for spawning five weeks after eyestalk ablation, and then reproductive performance was evaluated for 80 days. Mean spawn size was 315,000±28,920 (SE) eggs, with 195,000 ± 24,400 nauplii per spawn and 59.6 ± 5.61 percent hatch (N = 60). Mean weights were 146.6 and 104.5 g for females and males, respectively.

22.  THE USE OF EDTA IN AQUACULTURE:A POSSIBLE MECHANISM OF BROAD-SPECTRUM TOXICITY REDUCTION.

David E. Brune, Agricultural Engineering Department Clemson University, Clemson, SC 296340357. Albert Garcia, Agricultural Engineering Department Texas A&M University, College Station, TX 77843. Herschel A. Elliott, Agricultural Engineering Penn State University, University Park, PA 16802.

Disodium ethylenediamine tetraceate (EDTA) is routinely used in aqua-culture as a broad-spectrum “cure-all” in preventing metal toxicity to aquatic organisms. On the other hand, it is routinely used to keep certain essential metals in solution when needed for phytoplankton culture. The reaction of EDTA in multi-metal solutions is complex and not surprisingly the outcome of blind addition of EDTA to culture water produces highly variable results. Recently, the authors reported on the ability of EDTA to catalyze the oxidation of soluble Mn⁺⁺ to insoluble MnO₂ certain conditions. This paper offers evidence to suggest that higher than expected levels of Mn⁺⁺ are often times observed in aquaculture water supply, as a result of stabilization by inorganic and organic sequestering agents. Furthermore, it is demonstrated that chelation of Mn⁺⁺ by phosphate may be counteracted by the addition of low levels by EDTA. Once the metal ligand is competitively bound by EDTA, it is then possible to oxidize the EDTA-model complex to insoluble MnO₂., This mechanism is proposed as the basis of a possible technique for the removal of stabilized heavy metals from aquaculture water supply when they appear at concentrations higher than expected, based on predictions from chemical equilibrium relationships.

23.  MICROBIAL ACTIVITY AND GROWTH IN A BRACKISHWATER SHRIMP POND:SOME CURRENT METHODS COMPARED.

Jeff M. Burgett¹, Shaun M. Moss¹ and David M. Karl²

Bacteria and algae dominate the metabolism of semi-intensive aquaculture ponds, but few techniques have been developed to measure their activity and growth rates. Using water samples from a Hawaiian shrimp pond, we compared several current methods used to measure microbial growth rates, biomass and amino acid uptake.

Water column samples from early, middle and late stages of grow-out were separated into <1, <20 and < 335 μm. size fractions before each analysis. Growth rates and microbial carbon production were calculated from the rate of incorporation of ³H-adenine into nucleic acids. These results were compared to rates obtained using three concentrations of ³H-thymidine. Particulate ATP content was used to calculate total microbial biomass. The ratio of ATP and non-ATP luminescence was assessed as a possible index of growth rate. Algal biomass was measured by Chl a fluorescence. The uptake and respiration of 14_c-glutamate provided an estimate of heterotrophic potential within each size fraction. The uptake of ³H-glutamate gave an independent measure of the meta-bolism of this substrate.

The measured dependence of ³H-thymidine uptake on concentration, and its corporation into RNA and protein as well as DNA, suggests that the established protocol for this technique could lead to substantial errors in estimates of heterotrophic growth rates. Bacteria and algae smaller than 1 μm were at times the dominant planktonic organisms in the study pond. Essentially all glutamate was taken up by organisms < l μm implying that most active bacteria were not attached to particles. Microbial growth rates were inversely proportional to size. The relative reliability of the techniques and their potential in aqua-culture research are discussed.

¹Department of Zoology,
²Department of Oceanography University of Hawaii at Manoa.

24.  THE INCIDENCE AND EFFECTS OF THE VIRUS BACULOVIRUS PENAEI (BVP) ON THE PERFORMANCE OF PENAEUS VANNAMEI NURSERY PONDS.

Julian Calderon*, Nick Carpenter and David K. Kawahigashi Pesquera Acuesemilas S.A., Av. las Americas, Ed, Mecanos 5to. Piso, Ofs. 503–504, P.O. Box 191-P, Guayaquil Ecuador.

A field analysis for the presence of the virus Baculovirus Penaei (BVP) inclusion bodies was conducted on Penaeus vannamei juveniles at the Acuespecies S.A. nursery ponds in Ecuador. The study was conducted on 24 nursery ponds of 0.6 hectares over a period of four months. Three 30 shrimp samples per pond were taken on seven-day intervals until harvest. Twenty wet-mount examinations were taken from hepatopancreas of each shrimp. The weight of the shrimp were recorded. The production data will demonstrate that the presence of virus Baculovirus in the nursery phase is not a significant factor.

25.   CHINESE INTEGRATED AGRICULTURE AND AQUACULTURE:AN ECONOMICALLY AND ECOLOGICALLY EFFICIENT SYSTEM.

W.Y.B. Chang, Great Lakes Research Division University of Michigan, Ann Arbor, Michigan.

Aquaculture practice in China dates back more than 3,000 years with the first document on the culture of common carp (Cyprinus carpio) assembled in 500 B.C. by Fan Li, who described widely used culture methods of the time. This document showed that even this early in human history Chinese fish culture had been integrated with agricultural production. Since then many improvements have been made; the Chinese have perfected culture practice and led the world in per unit pond fish production (exceeding 10,000 kg/ha in 1985). Two main types of integrated agriculture/aquaculture practices are found in China today. Integrated pond aquaculture, which turns the wastes from animal husbandry and the by-products from fields into food and feed and uses a high fish stocking density and rotation in harvesting to achieve high rates of fish growth and production, is the principal method used. This is an efficient ecological system since the agricultural wastes are used to produce fish while the aquaculture wastes such as pond soil are used for crop production. Integrated lake farming systems have further improved 'this operational efficiency by reducing the problem of low dissolved oxygen and increasing the production of aquatic plants which have higher growth rate and are more efficient as fish feed than phytoplankton. My presentation will cover the basic ecological concept of Chinese integrated aquaculture, various operational models used in Chinese integrated aquaculture, and the economical benefits of the integrated culture systems.

26.   ACCUMULATION OF INORGANIC NITROGEN COMPOUNDS IN THE PRAWN PONDS.

Jiann-Chu Chen*, Ping-Chung Liu and Tzong-Shean Chin Department of Aquaculture, National Taiwan College of Marine Science and Technology, Keelung, Taiwan, 20224 Republic of China.

Inorganic nitrogen compounds were monitored both in the hatchery and grow-out ponds of Penaeus monodon in Taiwan. The newly hatched P. monodon nauplii were reared in the ponds (4 x 7 m) with a stocking density of 100 nauplii/L until they reached the 10–12th day of the postlarva stage. The P. monodon postlarvae (PL23–25) were cultured in the ponds (45 x 31 m) about four months with a stocking density of 143 postlarvae/m². There were changes in 0.021–0.650 mg/L ammonia-N, 0.003–0.031 mg/L NH₃-N, 0.001–0.078 mg/L N0₂-N, 0.013–0.184 mg/L NO₃-N and 0.010–1.281 mg/L ammonia-N, 0.001–0.133 mg/L NH₃-N, 0.002–0.069 mg/L NO₂-N, 0.003–0.112 mg/L NO3-N at the first and second trials in the hatchery ponds. There were changes in 0.002–6.598 mg/L ammonia-N, 0.002–0.136 mg/L NH₃-N, 0.013–4.543 mg/L NO₂-N and 0.018–0.520 mg/L NO₃-N in the grow-out ponds. Nitrate rather than ammonia contributes to the survival rate of larvae in the hatchery ponds. Higher concentrations of ammonia and nitrate affected the growth and survival in the grow-out ponds. Besides providing oxygenation, water replacement is suggested.

27.   INTENSIVE GROW-OUT TRIALS OF TIGER PRAWN AND RED-TAILED PRAWN IN TAIWAN.

Jiann-Chu Chen*, Ping-Chung Liu and Yao-Tsu Lin Department of Aquaculture, National Taiwan College of Marine Science and Technology, Keelung, Taiwan, 20224 Republic of China. Chin-Kai Lee, Ching Shing Shrimps Aquatic Farms, Tungkang Pintung, Taiwan, 92804 Republic of China.

One grow-out trial of the tiger prawn Penaeus monodon and two continuous trials of the red-tailed prawn P. penicillatus were operated in a highly inten-sive system in Taiwan. The P. monodon postlarvae (PL 25–27) of 600,000 were reared in six 0.14 ha ponds and the P. penicillatus postlarvae (PL 8–12) of 720,000 and 1,200,000 were reared in three 0.14 ha ponds, respectively. Each pond is 2.2 m depth and is installed with two 1-Hp paddlewheels. Both species of the prawns were only fed with commercially formulated feed four times a day. Yield obtained for P. monodon was 848–1,500 kg/0.14 ha with an average of 1,212 kg/0.14 ha. Whereas, yield was 4,650 kg/0.42 ha and 5,160 kg/0.42 ha for P. penicillatus at first trial. The production were also compared with those reported before and a survey from conventional grow-out farms. The pro-ductivity of this system producing P. monodon and P. penicillatus was 8.7–21 tonnes/ha/crop and 11–12 tonnes/ha/crop, respectively. The studies indicated that increasing stocking as well as air supply, controlling inlet and drainage of water flow and deepening water level are capable of elevating the production in a small impounding area.

28.   STUDY ON THE ELIMINATION OF AMMONIA AND NITRATE IN THE LAVICULTURE OF PRAWN,

Jiann-Chu Chen*, Ping-Chung Liu and Yao-Tsu Lin Department of Aquaculture, National Taiwan College of Marine Science and Technology, Keelung, Taiwan, 20224 Republic of China.

Since ammonia and nitrite, the most common toxicants, increased expo-nentially both in the hatchery and grow-out ponds many efforts have been made to eliminate or reduce the concentration of these chemicals. Besides water replacement, a well balanced ecosystem is considered for the ponds having microorganisms, algae, Artemia nauplii, artificial feed and prawn larvae. Tiger prawn, Penaeus monodon postlarvae were cultured in the holding tanks with and without adding nitrifying bacteria solution, repectively. Parameters of ammonia, nitrite, nitrate, sulfide and chemical oxygen demand (COD), etc. and growth and survival of the animals were monitored. The results indicated that an appropriate use of nitrifying bacteria could help reduce the ammonia and nitrite concentrations in both closed and recirculated systems. The postlarvae reared in the recirculated system has better growth and survival than those in the closed system. A new hatchery system with recirculated water developed for commercial use is suggested.

29.   QUALITATIVE LIPID REQUIREMENTS OF MILKFISH (CHANOS CHANOS) JUVENILES FED PURIFIED DIETS,

Andrew Chiaraviglio*, Marine Sciences Research Center State University of New York at Stony Brook (SUNY) Stony Brook, NY 11790 USA. Warren G. Dominy, The Oceanic Institute, Makapuu Point, Waimanalo, HI 96795 USA.

Five purified diets, diferring only in their lipid source, were fed to juvenile milkfish (Chanos chanos). Dietary lipids were selected to cover a wide range of omega 3:omega 6 fatty acid ratios, and to provide different degrees of unsaturation. The control diet was lipid free, and the four remaining diets contained one of the following oils, added at a 10% inclusion level:coconut oil, soybean oil, menhaden oil and mixture composed of 3 parts menhaden to 7 parts soybean oil.

After 21 days, the best growth performance (85% increase in body weight) was observed in fish receiving the diet supplemented with the 3:7 mixture of menhaden and soybean oil, followed by those receiving the diet supplemented with coconut oil (69.3% increase). Growth performance of fish receiving the diets supplemented with menhaden oil and soybean oil was virtually identical (61.5%). Growth was poorest (47.3%) in milkfish receiving the lipid-free control diet. Survival rate was 100% for milkfish receiving the diets sup-plemented with 10% lipid, and 96% for those receiving the lipid-free survival, and feed conversion, the diet supplemented with a 3:7 mixture of menhaden and soybean oil came closest to providing an adequate source of dietary lipids for juvenile milkfish.

30.   THE EFFECTS OF AGED SEDIMENT AND STOCKING DENSITIES ON FRESHWATER PRAWN MACROBRACHIUM ROSENBERGII CULTURE.

Yew-Hu Chien*, Department of Aquaculture Hong-Tsu Lai, Institute of Fisheries, National Taiwan College of Marine Science and Technology, Keelung Taiwan, R.O.C.

Excess feed and metabolites from intensive culture system always cause deterioration of the sediment and water quality. To assess the effects of aged sediment and stocking densities on the freshwater prawn Macrobrachium rosenbergii culture, 32 tanks were assigned to 16 treatments in a 4 x 4 factorial arrangement; 4 stocking densities:0, 16, 23, 31/m² by sediment of 0 ooze content:0, 25, 50, 100%. Survival and growth of prawn were recorded routinely, water and sediment were analyzed. Besides the density factor, increase of NH₃, NO₂-, and NO₃- in surface sediment was the reason which caused the growth retardation when stocking density increased. Constant aeration might keep the toxic substance under lethal level and result in insignificant difference in mortality among treatments. The increase of ooze content enhanced the drop of Eh (redox potential), the increase of TN (total N), NH₃ and S²- in the sediment. Crawling activity of prawn and constant aeration kept the Eh above highly reduced level and minimized the differences of sulfide among treatments of various stocking densities. Along with the increase of stocking density, NO₃- and NH₃ in water, surface and subsurface sediment, TN in surface sediment, TN, NO₂- and sulfide in sub-surface sediment increased.

31.   CHOLESTEROL REQUIREMENT OF POSTLARVAL PENAEUS VANNAMEI.

Ann E. Clark* and Addison Lawrence, Shrimp Mariculture Project, Texas Agricultural Experiment Station, Texas A&M University System, P.O. Drawer Q, Port Aransas Texas 78373.

A purified diet was used within an innovative experimental system to determine the cholesterol requirement of Penaeus vannamei. Cholesterol is a dietary essential due to its inability to be synthesized de novo. Post-larval shrimp averaging 63 ± 14 mg and 58± 7 mg were fed casein-gelatin based purified diets containing varying levels of cholesterol. The levels tested were 0%, .5%, 1%, 2%, and 4%. Data suggests that the minimum requirement for good growth is .5%. Growth at this level after 14 days averaged 679± 64% and 672 ± 103%, survival averaged 93 ± 5% and 92 ± 12%.

32.   LECITHIN REQUIREMENT OF POSTLARVAL PENAEUS VANNAMEI,

Ann E. Clark* and Addison Lawrence, Shrimp Mariculture Project, Texas Agricultural Experiment Station Texas A&M University System, P.O. Drawer Q Port Aransas, Texas 78373.

The lecithin requirement of Penaeus vannamei was evaluated using a casein-gelatin based purified diet. Lecithin is a questionnable essential lipid in shrimp diets, especially because of its varying fatty acid composition. Post-larval shrimp averaging 63± 14 mg and 58 ±7 mg were fed diets containing different levels of soy lecithin. The levels tested were 0%, .5%, 1%, 2%, 4% and 8%. Results suggest that the requirement is between 2% and 8%. Growth at these levels after 14 days ranged from 596± 120% to 688± 126%. Survival ranged from 68 ± 4% to 91 ± 9%.

33.   A NEW SYSTEM FOR DOUBLE CROPPING SHRIMP.

Harry L. Cook*, Richard A. Creelman and Ed Cook Ocean Ventures, Inc., Port Lavaca, TX 77979, USA.

The purpose of this research was to investigate the feasibility of a method of managing ponds to produce more than one crop of shrimp per year along the Gulf of Mexico. The culture unit was comprised of three growing ponds of 2.2 acres each which are inter-connected by sluice gates. The two exterior ponds were stocked in May with shrimp which had been head-started in a covered nursery. Stocking density was about 28,000 per acre. At about the same time 660,000 postlarvae (5–6 mm) were stocked in the middle pond. The two outside ponds were harvested in late July. These ponds were then refilled and restocked by opening the sluice gates connecting them to the middle pond. Large juveniles from the middle pond swam into the newly refilled ponds. All three ponds were harvested in early November.

34.   POLYCHAETE BIOMASS AS AN INDICATOR OF NATURAL PRODUCTIVITY IN PENAEID SHRIMP CULTURE PONDS.

Jack Crockett*, Leslie Sturmer, Addison Lawrence and John Whitson, Shrimp Mariculture Project, Texas Agricultural Experiment Station, Texas A&M University System, 4301 Waldron Road Corpus Christi, Texas 78418.

Benthic polychaete worms contribute significantly to the nutritional requirements of penaeid shrimp cultured in ponds. There exists a complex relationship between feed, polychaete population and shrimp population. To facilitate the study of this dynamic interaction, a practical method of monitoring polychaete population was developed.

Core samples were taken on a weekly basis from six 0.1 ha ponds stocked with 10.13 juvenile Penaeus vannamei per m². The samples were washed in a benthos bucket. Material retained on a 500 μ screen was immersed in 10% buffered formalin solution containing rose bengal stain for 24 hours. A second washing through a 2 mm screen supported over a 500 μ screen separated polychaetes from detritus and compacted substrate. Polychaetes were isolated from any remaining material with forces and counted. They were dried at 95°C for 75 minutes and weighed to the nearest 0.01 mg,

Biomass of dried polychaetes ranged from 0.119 to 3.870 g per m² while polychaete density varied from 1,919 to 22,311 organisms per m². The average individual weight of dried polychaetes fluctuated from 0.02 mg to 0.55 mg.

Biomass measurements provided a more accurate indication of the nutri-tional potential of a polychaete population, as variation of average individual weight caused numbers of polychaetes to be misleading. The relationships bet-ween polychaete biomass, shrimp biomass and feed are discussed.

35.   OPTIMAL DIETARY PROTEIN LEVEL FOR JUVENILE FRESHWATER PRAWN MACROBRACHIUM ROSENBERGII.

Louis R. D'Abramo and Laurieann Reed, Department of Wildlife and Fisheries, Mississippi State University Mississippi State MS 39762 USA.

Juvenile freshwater prawn Macrobrachium rosenbergii were fed purified isoenergetic diets containing protein levels of 15, 20, 25, 30 and 35%. Purified crab protein served almost exclusively as the protein source. After 90 days and at least 12 molts survival and weight gain was determined. The mean wet weight increased with increasing protein levels. Significant differences in wet weight existed between all groups except those that were fed the 25 and 30% protein levels. The observed significant reductions in weight gain were the result of decreases in wet weight increase/molt rather than a protraction of the time interval between each successive molt. The optimal dietary protein level for juvenile freshwater prawn is estimated to be between 33 and 35% (dry weight).

36.   PREDATION RATE OF TIGER SHRIMP (PENAEUS MONODON) LARVAE ON ROTIFER (BRACHIONUS PLICATILIS).

Edward Danakusumah, Bojonegara Research Station for Coastal Aquaculture, P.O. Box 01, Bojonegara Cilegon-42454, Indonesia.Dadi Koswara, Faculty of Fisheries, Bogor Agricultural University Darmaga, Bogor, Indonesia.

Experiments on the predation rate of tiger shrimp (Penaeus monodon) larvae on rotifer (Brachionus plicatilis) had been conducted under laboratory conditions. The study was aimed to understand the rotifer requirement of P. monodon larvae. The larvae were cultured in beakers of 1,000 ml capacity. They were fed with rotifers at different densities of 10, 20 and 30 individuals per ml.

Result showed linear relationship between density of rotifer and pre-dation rate. To some extent, the higher rotifer density, the higher predation rate. Relationship between larval substage and predation rate showed quadratic curve. Most active predation was found between Mysis-1 and Mysis-2.

37.   AN INTEGRATED DISSOLVED OXYGEN MONITORING AND CONTROL SYSTEM, INCLUDING TOTAL DATA MANAGEMENT CAPABILITY, FOR A COMMERCIAL AQUACULTURE OPERATION.

Jim Dartez*, Royce Instrument Corporation
4301 Poche Court West, New Orleans
Louisiana 70129.

Dissolved oxygen (DO) monitoring has become one of the most important operational criteria in commercial aquaculture operations. Natural environ-mental conditions often tend to change the DO holding capacity of water, some-times in very short periods of time. These changes require excessive manpower usage and often cause increased expenses due to the “overuse” of aeration equipment of oxygen generating equipment.

Continuous monitoring DO instrumentation can now be combined with automatic paging systems, alarms, and/or computer control and data management systems for the purposes of saving the aquaculturist money and allowing him to work smarter in controlling this very important parameter. With new monitoring technologies like self-cleaning DO sensors, proportional control capabilities, etc. the grower acquires the necessary control of the water conditions that are so important for the well-being of his stock. Existing continuous monitoring systems, with various levels of automation, are shown and discussed. Financial considerations are explored and cost justifications defined.

38.   EFFECTS OF FERTILIZATION RATE ON PRIMARY PRODUCTION AND YIELD OF TILAPIA IN PONDS.

James S. Diana* and C. Kwei Lin, Great Lakes and Marine Water Center, University of Michigan, Ann Arbor Michigan 48109 USA.

Carrying capacity in extensive fish culture ponds is constituted by the quality and quantity of food stuff, as well as water quality. These are influenced primarily by the nature and quantity of the fertilizers applied. We conducted a series of fertilization experiments in earthen ponds in Thailand to determine the carrying capacity for optimal tilapia (Oreochromis niloticus) production. The experiments involved applications of:1) inorganic phosphate; 2) phosphate and urea; and 3) organic fertilizer. Each experiment was run in 3–4 replicates for a 5-month period. Fish yield, production of potential food organisms (plankton and benthos) and water quality were determined in response to respective fertilizer application. The results show that the pond carrying capacity ranged 'below the poverty line' to 'excessively wasteful' situations. Based on equal amount of P and N fertility, the organic fertilizer (chicken manure) created greater pond carrying capacity than the inorganic fertilizer. An optimal carrying capacity was established in ponds receiving chicken manure at a rate of 500 kg/ha/week, which produced average organic carbon at 100 kg/ha/day and fish yield at 24 kg/ha/day, The indirect food conversion ratio of chicken manure was 3 and the net organic carbon conversion ratio was approximately 5.

39.   CHARACTERIZATION OF LEACHING RATE IN SHRIMP FEEDS:MEASUREMENTS OF LOSS IN WEIGHT AND ORGANIC MATTER.

S. Divakaran* and Eirik 0. Duerr, The Oceanic Institute Makapuu Point, Waimanalo, HI 96795 USA.

The rate of leaching and consequent loss of macronutrients from five commercial shrimp feeds was determined by measuring their loss in weight and non-volatile organic matter. Weight loss and leaching of organic matter from the feed material into water containing 32 ppt sodium chloride was measured at eight time intervals (from 4 to 48 hours). Loss of non-volatile organic matter was measured by colorimetry as the amount of dichromate reduced from a 5% solution of potassium dichromate in 95% sulfuric acid. A close correlation was observed between weight loss (which included the loss of both organic and water-soluble in organic constituents) and the loss of organic matter. The method described above can be useful in determining the total loss of water-soluble organic macronutrients (e.g. soluble proteins, crystalline amino acids, soluble carbohydrates, vitamins) from shrimp feeds.

40.   BIOCHEMICAL COMPARISON BETWEEN DIPLOID AND TRIPLOID PACIFIC OYSTERS (CRASSOSTREA GIGAS).

Sandra L. Downing*, Teri L. King, S.K. Allen and Kenneth K. Chew, School of Fisheries WH-10 University of Washington, Seattle, WA 98195 USA.

Diploid and triploid cohort oysters, Crassostrea gigas, were sampled at various times during their reproductive cycle, and their biochemical components quantified. A majority of the sampling was carried out in the summer when triploid Pacific oysters devote 60–75% less effort to reproduction than diploids. Proximate analysis was done using the kjeldahl method for protein a phosphosul-phovanillin method for lipids, and anthrone method for glycogen (carbohydrates) and a muffle furnace to determine ash.

Diploid and triploids have a significantly different biochemical patterns. Glycogen levels decreased in diploids from winter values of 30% (dw) to a mini-mum of 6% at the peak of gametogenesis. Protein in diploids rose from 30% to 80% in midsummer; it appears to be the major component of gametes. Diploid lipid values increased at the start of gametogenesis, but then slowly declined. The annual biochemical patterns for triploids were more consistent. Although delayed and less extreme, the same inverse relationship between glycogen and protein is observed during gametogenesis. Spawning seems to have been detri-mental to diploids as the triploid percentage significantly changed between the pre- and post-spawning samples. After spawning, diploid and triploid composition patterns paralleled each other as they slowly return to winter levels when oysters contain similar amounts of the biochemical components. The implications of the different biochemical patterns for marketing triploid oysters will be discussed.

41.  OPTIMAL DEPTH AND CULTURE DENSITY FOR PRODUCTION OF SPIRULINA PLATENSIS IN OUTDOOR CIRCULATING ALGAL RACEWAYS.

Eirik O. Duerr*, The Oceanic Institute, Makapuu Point Waimanalo HI 96795 USA.
Donald W, Freeman, USDA-ARS Tropical Aquaculture Research Unit The Oceanic Institute, Makapuu Point, Waimanalo HI 96795 USA. Paul K. Bienfang, The Oceanic Institute, Makapuu Point Waimanalo, HI 96795 USA.

Optimization of the light regimen to which an algal culture is exposed is a critical consideration in the design and operation of an algal production system. Artificial light supplementation is not cost-effective for large-scale outdoor cultures; methods of optimizing available solar radiation in the culture are therefore required. The bluegreen alga Spirulina platensis was cultured in outdoor circulating algal raceways (5.9 m² each) which were managed at three depths (10, 15 or 20 cm) at a given culture density. A total of four densities (0.2, 0.4, 0.6 or 0.8 O.D._{680 nm}) were examined at each depth. Productivity was determined daily before culture conditions were reestablished by harvesting back the net biomass increase. At the lower densities and depths, growth was inhibited by excess light; at the higher densities and depths, it was inhibited due to insufficient light. Results suggested that a depth of 10–15 cm, combined with a harvesting schedule that kept the culture density close to 0.6 O.D._{680 nm}, provided an optimal algal culture regimen.

42.   STATUS AND PROBLEMS OF MASS PRODUCTION OF GREY MULLET, MUGIL CEPEALUS.

H. Eda*, C.S. Lee, R.A. Clarke and D.J. Shiraishi
Oceanic Institute, Makapuu Point, Waimanalo
HI 96795 USA.

Progress in artificial propagation of grey mullet (Mugil cephalus) has been impeded by the lack of reliable hatchery techniques. In this study, hatchery procedures used in Japan for culturing red sea bream were tested on mullet larvae.

Fertilized eggs were obtained from hormonally induced spawns during the 1986 mullet spawning season (Dec–Mar.). These eggs were hatched in 1,000-liter, open system incubation tanks. Newly hatched larvae were divided into 5,000-liter tanks (N = 8) at a density of 20 individuals per liter. Mullet larvae initially feed 65 hours after hatching at 24°C and average 3.3 mm in total length.

The feeding program was initiated by the introduction at first feeding of s-type rotifers at a density of 5–20 individuals/ml. Chlorella sp. was also stocked at a density of 500 x 10³ cells/ml. Chlorella and rotifer densities are maintained until day 30 and 70, respectively. From day 30, artificial feed (ground shrimp food at 42% protein) was supplemented. Newly hatched Artemia were also utilized between days 30–50. During this period, Artemia densities increased from 0.1 to 2 individuals per ml. Survival rates among the 100,000 mullet juveniles produced during a 6 man-month period ranged between 9 and 25%. The apparent key to larval rearing success is the availability of a sufficient quantity of food.

43.   EVALUATION OF VARIOUS GROWTH ENHANCEMENT FACTORS, MEDIA FORMULATIONS, AND SUPPORT MATRICES FOR THE DEVELOPMENT OF PRIMARY AND ESTABLISHED CELL LINES FROM PENAEUS HEPATOPANCREAS.

R.D. Ellender*, B.L. Middlebrooks and S.L. McGuire University of Southern Mississippi, Hattiesburg, MS 39406 USA. R.M. Overstreet, Gulf Coast Research Laboratory Ocean Springs, MS 39565 USA.

The development of diagnostic methods to detect baculovirus penaei (BP) in cultured shrimp populations has been hampered by a lack of sufficient anti-genic material. Cells liberated from hepatopancreatic tissue (HP) of Penaeus vannamei by mechanical treatment were evaluated as source material for develop-ment of cell lines suitable for BP virus replication.

HP cells were released from cecae by mechanical agitation; they attached to Cytodex 2 beads and to agar but not the 6 other matrices. The buoyant density of HP cells was determined by Ficoll centrifugation to vary from 1.016 to 1.033 g/ml. HP suspended cell populations could be subcultivated 4 x (during 2–1/2 mts) in L-15 containing 10% fetal bovine serum and 1% L-glutamine. Cells formed epithelial monolayers on agar surfaces and could be maintained for at least one month exposed to the atmosphere of the flask. BP virus replication was evident in infected, primary cells and demonstrated by the formation of polyhedra.

Mixed HP cell cultures were also established in several growth media (Schneider's drosophila medium, Grace's insect medium, RPMI 1640, MEM, Bulbecco's modified MEM) supplemented with 15% FBS along with various com-binations of mammalism cell growth factors. In these studies, best results were obtained using RPMI 1640 or DMEM supplemented with a combinations of growth factors have produced indications of enhanced cell survival. Three subcultivations have been made over a period of 2 months. Poor culture survival was obtained using Grace's or Schneider's media.

44.   AN ECONOMICAL COMPARISON OF AERATION DEVICES FOR AQUACULTURE PONDS.

Carole R. Engle*, Economics Department, Auburn
University at Montgomery, Montgomery, Alabama 36193–0401.

The physical efficiency of aeration devices has been tested, but the economic efficiency of aerators used in aquaculture ponds has not been deter-mined. Fixed and variable costs were determined and compared for 25 types of aeration devices that included:floating, electric and tractor-powered versions of paddlewheel, pump sprayer, vertical pump, propeller-aspirator pump and diffuser aerators. A linear programming computer model was developed to mini-mize total annual cost of aeration given different pond sizes, different aeration strategies and different farm sizes.

Fixed costs varied from S125 to $1,233 per horse-power per year and comprised from 60 to 90% of total annual cost per aerator depending on the aeration strategy. A farmer's choice of an aerator should be based primarily on the quality of construction, maintenance and repair requirements as well as its operating efficiency. Fiberglass and metal floatation devices and frames will have significantly lower annual depreciation costs than styrofoam floats and plastic frames while those with simpler designs will have lower maintenance and repair costs.

The LP model selected optimal systems for different farm resource situations based on minimum total annual cost. The most cost-efficient aeration systems were determined for:1) 0,4, 1, 2, 4, 8 and 20-hectare ponds:2) Water-shed versus seine-through ponds; 3) 8, 20, 40, 80, 200 and 280-hectare farms. Economic trade-offs between emergency and continuous aeration were discussed. The additional production needed to justify the additional expense of aeration was calculated for the alternatives considered.

45.   DESCRIPTION OF A MEDIUM SCALE PENAEID MATURATION SYSTEM IN THE PHILIPPINES.

Eleanor D. Enriquez*, 18 Tanguile Street
Veterans' Village, Project 7
Quezon City, Philippines 3008.

An 8-tank maturation unit was established to supply year round viable nauplii for a Penaeus monodon hatchery whose target production was 2 million postlarvae 15 per month. No broodstock was maintained. Spawners came from either an estuarine or the open sea. All females are tagged to monitor indi-vidual spawning performance. Daily checking is accomplished to lessen the possibility of spawns occurring inside the tank. No spawning tanks are utilized. Gravid females are transferred directly to larval tanks in batches of 3 to 4 per tank. No egg counts, fertility or hatching rates are determined. All unhatched eggs and weak nauplii are siphoned out for two consecutive mornings after the spawn, leaving only healthy, phototactic nauplii in the larval tank. Count at N4 is used as a measure of total viable nauplii. Survival from nauplii to the first protozoal stage is recorded. Daily nauplii production ranged from .5 to .6 million. Materials and methods are discussed in detail as well as production results and observations.

46.   PRODUCTION OF FLORIDA RED HYBRID TILAPIA (FEMALE OREOCHROMIS UROLEPIS HORNORUM X MALE O. MOSSAMBICUS IN FED AND MANURED SEAWATER POOLS.

Douglas H. Ernst*, Lisa J. Ellingson and Robert I Wicklund Caribbean Marine Research Center, 100 E. 17th Street
Riviera Beach, FL 33404 USA.
Fori L. Olla, Cooperative Institute for Marine Resource Studies, Northwest and Alaska Fisheries Center, National Marine Fisheries Service, Hatfield Marine Science Center Newport, Oregon 97365 USA.

Florida red hybrid tilapia (Oreochrbmis urolepis hornorum female x O mossambicus male) were reared in seawater pools in the central Bahamas. Fish (1.3 g mean weight) were stocked in eight plastic-lined pools (23 m³) at a density of 25/m³ (250,000/ha). Fish in four pools received floating pelletized feed (30% protein) three times per day to appetite satiation and four pools received daily application of chicken manure at 105 kg/ha/day (dry weight). All pools received continuous diffused aeration at 57 1pm and flow-through seawater providing a daily exchange of a 4.0 and 0,1 times for fed and manured pools, respectively. Water temperature averaged 27°C and salinity averaged 37 ppt.

In fed pools, mean fish weight was 114 g after 80 days at a survival rate of 92%. After 170 days, mean fish weight was 467 g at a survival rate of 89%. Over the 170 day period, fish productivity increased to 806 kg/ha/day and the food conversion tatio (dry weight:wet weight) was 1.7. Expressed in logarithmic (natural) form, growth rate (% weight/day) and feeding rate (% weight/day) were linear functions of fish weight.

In manured pools, mean fish weight was 19 g after 80 days at a survival rate of 70%. Mean fish productivity increased to 80 kg/ha/day over the first 20 days, as in fed pools, but declined over the remaining 60 days to less than 10 kg/ha/day. Mean productivity over 80 days was 32 kg/ha/day for manured pools and 270 kg/ha/day for fed pools.

Water quality, bacterial productivity, phytopiankton and macroalgae productivity and plankton density and composition were also measured and their relationship to fish productivity examined.

47.   RICE-CRUSTACEAN CULTURE:POTENTIAL IN SOUTHEAST ASIA.

Arnold G. Eversole*, Department of Aquaculture
Fisheries and Wildlife, Clemson University
Clemson, SC 29634–0362 USA.
Robert S. Pomeroy, Department of Agricultural
Economics, Clemson University, Clemson
SC 29634 USA.

Rice, the dominant cereal crop in Asia, is cultured on 21 million ha and annually produced a by-product of over 1,000 million tons of straw, leaf, bran and hull in Asia. These represent a potential resource for aquaculture which except for a small percentage of the area (=1%) used for rice-fish culture, remains practically an untapped resource. Interest in rice-fish culture in Asia declined with the increased use of pesticides during the Green Revolution, but with the recent development of new high-yielding resistant rice varieties and natural pest control agents, there has been renewed interest. Any species which could directly utilize the nongrain parts of rice or the microcommunity colonizing the nongran parts should integrate well in a rice based aquaculture system.

The thesis of this presentation is to explore the role of a crustacean in a rice culture system reviewing the advantages (e.g. increased yield/ha) and constraints (e.g. pesticide use). The methods of rice-crawfish culture in the United States are discussed with comparisons to the few studies of rice-crustacean culture in Southeast Asia. The prospectus of adding income to the producer is evaluated and recommendations are made for considering future development.

48.   A DESCRIPTION OF MARINE SHRIMP CULTURE IN TAIWAN AND ITS SIMULATED TRANSFER TO HAWAII.

Arlo W. Fast*, Hawaii Institute of Marine Biology (HIMB)
Kaneohe, HI 96744 USA.
Y.C. Shang, Department of Agricultural Economics
University of Hawaii, Honolulu, HI.
Gary L. Roger, HIMB, I.C. Liao, Tungkang Marine
Laboratory. R.O.C.

Eleven intensive style marine shrimp farms were surveyed in southern Taiwan and descriptions of these farms are presented. Based on these descrip-tions, we constructed a model of a well-run Taiwan shrimp farm. We then con-ducted an economic analysis of this hypothetical farm in Taiwan and its simulated transfer to Hawaii. Comparisons are made.

49.   THE NUTRITIONAL RESPONSES OF THREE SPECIES OF POSTLARVAL PENAEID SHRIMP TO COTTONSEED MEAL.

Renita R. Fernandez* and Addison L. Lawrence, Shrimp Mariculture Project, Texas Agricultural Experiment Station Texas A&M University System, P.O. Drawer Q, Port Aransas Texas 78373.

This study investigates the use of cottonseed meal, a low-cost high protein source, in the diets of postlarvae for three penaeid shrimp species, Penaeus setiferus, P. stylirostris and P. vannamei. Four cottonseed meal levels, 0%, 5%, 10% and 20%, for two protein levels, 20% and 30%, were evaluated using 19 liter tanks in the laboratory. Survival ranged from 91–100% for P. setiferus, 84–95% for P. stylirostris and 98–100% for P. vannamei. For all three shrimp species tested, shrimp fed the higher protein level of 30% exhibited significantly higher final mean weights, average weight gains and present weight gains than those fed the lower protein level of 20%. For feeds containing 30% protein, both P. vannamei and P. stylirostris showed no significant differences in final weights for all cottonseed meal levels tested. However, P. setiferus showed a significant decrease in growth when fed diets containing 20% cottonseed meal at 30% protein. For feeds containing 20% protein, up to 10% cottonseed meal may be added to P. vannamei and P. styli-rostris feeds without significantly affecting growth. Adding 5% or higher levels of cottonseed to 20% protein diets for P. setiferus causes a significant decrease in weight gain. The data indicate that different levels of cottonseed meal can be used in the diet of penaeid shrimp depending upon the shrimp species and protein level in the diet.

50.   NUTRITIONAL RESPONSE OF POSTLARVAL PENAEUS VANNAMEI TO DIFFERENT SOYBEAN LEVELS.

Renita R. Fernandez* and Addison L. Lawrence
Shrimp Mariculture Project, Texas Agricultural
Experiment Station, Texas A&M University System
P.O. Drawer Q, Port Aransas, TX 78373.

This paper investigates the nutritional response of 0.04 g Penaeus vannamei to different levels of soybean meal using 19 liter tanks in the laboratory. At 25% and 35% protein levels, 15%, 25%, 45% and 53% and 30%, 45%, 60% and 75% soybean levels were tested, respectively. Survival at the 25% protein level was significantly better than survival at 35% protein. Survival of shrimp fed 25% and 35% protein diets was 76–95% and 86–96%, respectively. Differences in survival between soybean levels within each of the two protein levels tested were not significant. Growth, in terms of final mean weight, over a 14 day experimental period was not significantly different for the two protein levels tested. Comparisons of the various diets tested on P. vannamei suggest that in diets containing soybean meal, feeding at a lower protein level (25%) gives better survival with no significant decrease in growth. Furthermore, for 35% protein diets, 45% to 60% soybean meal can be added without significantly affecting growth. Adding 75% soybean meal causes a slight decrease in weight. The presence of 25–53% soybean meal is advantageous in feeds containing 25% protein. This study complements previous studies done on juvenile and subadult penaeid shrimp.