bluuebunny/crossref_metadata_2025 huggingface dataset:
Fingerling Production Of Striped Bass (Morone Saxatilis), Spotted Seatrout (Cynoscion Nebulosus), And Red Drum (Sciaenops Ocellatus), In Saltwater Ponds1
Authors: Colura Robert L. , Hysmith Bruce T. , Stevens Robert E.
Published: August 2010

Striped bass (Morone saxatilis) production in two ponds (0.5 ha) at the Marine Fisheries Research Station, Palacios, Texas, during 1975 totalled 55, 645 fingerlings (11, 290/ha) averaging 41 mm in TL. Overall survival was 55.6%. Thirty thousand 7‐day‐old fry stocked in 0.1 ha pond produced 5,245 fingerlings (52, 450/ha) in 40 days or 0.75 kg/ha/day. Survival was 17%. Seventy thousand 6‐day‐old fry stocked in a 0.4 ha pond produced 50, 400 fingerlings (126, 000/ha) in 45 days or 1.68 kg/ha/day. Survival was 72%.

Spotted seatrout (Cynoscion nebulosus) production in nine ponds (1.23 ha) during 1975 totalled 6, 230 fingerlings (5, 065/ha) averaging 48.7 mm TL. Production ranged from 0.00 to 0.89 kg/ha/day. Overall survival was 3% ranging from 0. to 18.6%. Copepods comprised 55.6% of the diet of spotted seatrout less than 25 mm TL. Spotted seatrout 25 mm TL or greater fed primarily on polycheates (40.5%) and secondarily on palemonid shrimp (34.2%).

Red drum (Sciaenops ocellata) production in 10 ponds (4.8 ha) during 1975 totalled 295, 119 fingerlings (61, 483/ha) averaging 39.6 mm TL. Production ranged from 0.13 to 2.17 kg/ha/day. Overall survival was 20% ranging from 1.9 to 65.0%. Red drum less than 25 mm TL fed almost exclusively on copepods (97.3%). Copepods (50%) and aquatic insects (45.4%) were the primary and secondary food items of red drum 25 mm TL or greater.
Culturing Yellow Perch (Perca Flavescens) Under Controlled Environmental Conditions For The Upper Midwest Market1
Authors: Calbert H. E. , Huh H. T.
Published: August 2010

Yellow perch (Perca flavescens) are in great demand in the upper midwest around the Great Lakes area. The supply of this species from natural waters is declining rapidly while the demand is increasing. To supplement the natural supply a system of culture for this species under controlled environmental conditions has been developed at the University of Wisconsin‐Madison. The fish are raised from fingerling to market size (150 g) in 9 to 11 months on a pelleted feed at water temperatures of 21 C and photoperiods of 16 hr. The water used in the system is cycled through biological filters so that it can be used approximately 20 times. Feed conversion is approximately 1.5. The fish have an excellent flavor and yield approximately 5% more fillets than fish from natural waters.
A Food Supplement From Biomass Growth In Terminal Sewage Lagoons1
Authors: Schurr Karl
Published: August 2010

Properly constructed sewage lagoons offer an inexpensive alternative to activated sludge and trickling filter treatment. Lagoons are more efficient, and convert sewage nutrients to plants and invertebrates. Dietary salt and water softeners produce mixomesohaline conditions in lagoon mariculture.

Laboratory evaluation of lagoon biomass has shown a potential for animal food. We have determined the amino acid, lipid, carbohydrate and ash content in the product. In addition, the levels of vitamins (biotin, cobalamin, naicin, pantothenic acid, total B6, riboflavin and thiamine) have been found in the biomass. Our evidence on the fate of enteric pathogens compliments well‐documented studies at other laboratories which indicate that the material is safe for consumption.

Integration of sewage lagoons, with other types of sewage treatment is possible in order to provide the lowest cost of sewage treatment, with the potential for production of a nutritionally valuable food supplement.
Effect Of Salinity On Growth And Survival Of Penaeid Shrimp In Ponds1
Authors: Hysmith Bruce T. , Colura Robert L.
Published: August 2010

Brown shrimp did not survive an initial 32 days of pond culture at 7 ppt. At 15 ppt salinity, survival was 6.7% and production was 78.4 kg/ha. Both survival and production were best at 21 ppt amounting to 20.8% and 185.3 kg/ha, respectively. At harvest, brown shrimp had a heads‐on count of 86 and 108/kg at 15 and 21 ppt, respectively.

White shrimp survival increased with increasing salinity averaging 12.7, 43.8 and 60%, respectively, for the three levels of salinity. Production, amounted to 121.5 kg/ha at 7 ppt, 452.5 kg/ha at 15 ppt and 416.6 kg/ha at 21 ppt. At harvest, white shrimp had a heads‐on count of 101, 95 and 141/kg at 7, 15 and 21 ppt, respectively.

Growth of both species seemed to vary inversely with survival. Coefficient of condition (K) averaged 8.5 for brown shrimp and 7.2 for white shrimp.
A Survey Of The Diseases Of Striped Bass, Morone saxatilisAnd Pompano, Trachinotus carolinus Cultured In Earthen Ponds1
Authors: Hawke John P.
Published: August 2010

Routine examinations of pond culture pompano (Trachinotus carolinus) and striped bass (Morone saxatilis) for diseases were conducted at the Claude Peteet Mariculture Center, Gulf Shores, Alabama and on striped bass cultured in fresh water ponds at the Auburn University Agricultural Experiment Station from June, 1974 through October, 1975. Pathogenic bacteria were isolated from striped bass and pompano. Protozoan parasites were found infesting pompano in brackish water and striped bass in fresh and brackish water. The identify, level of infection and response to treatment of each disease organism is discussed.
The Susceptibility Of Cultured American Lobsters To A Chitinolytic Bacterium1
Authors: Fisher W.S. , Rosemark T.R. , Nilson E.H.
Published: August 2010

Juvenile American lobsters (Homarus americanus) cultured at the Bodega Marine Laboratory were found to be susceptible to a chitinolytic bacterium under certain stress conditions. Under optimal conditions the animals were uneffected by the organisms. The greatest susceptibility was found on animals fed a long‐term synthetic diet and on animals that were treated with malachite green and fed on a short‐term synthetic diet. Excised appendages, carapace abrasion and heavy bacterial inoculation did not increase susceptibility.
Survival And Growth Of Juveniles Of The Giant Malaysian Prawn, Macrobrachium rosenbergii, Fed Natural Plant Diets
Authors: Stern Henrietta L. , Armstrong David A. , Knight Allen W. , Chippendale Deborah J.
Published: August 2010

Several aquatic plants (Azolla filiculoides, Cladophora sp., Elodea sp., and Lemna sp.) were fed singly to groups of 30 juvenile Malaysian prawns (Macrobrachium rosenbergii) for 28 days, and comparisons were made with control prawns fed Ralston Purina Ration #20. The comparisons made were survival, weight change, and molting frequency.

The animals ingested all diets during the experiment, though none on a plant diet fared as well as the controls in weight gains and survival by day 28. The controls increased 65% in dry weight, whereas the others lost weight. The control group had significantly higher survival by day 28, although on day 16 survival was better only than that of the Cladophora‐fed group. Most deaths of plantfed prawns were in the last week of the experiment, whereas the control group had no deaths after day 9. In general, molting peaks occurred in 8–10 day cycles, and all groups molted less in the latter half of the experiment. Group percents for molting during various periods were consistently highest for controls. Molt/day, averaged over 28 days, was 7.3, 2.5, 4.0, 3.8, and 5.0% for the control, Azolla, Cladophora, Elodea, and Lemna groups, respectively.

A single‐species plant diet apparently did not satisfy the nutritional requirements of the prawn as indicated by increased mortality and decreased weight.
THE PURPLE‐HINGE ROCK SCALLOP: A NEW CANDIDATE FOR MARINE AQUACULTURE1
Authors: Leighton D. L. , Phleger C. F.
Published: August 2010

Studies on spawning and larval culture in the purple‐hinge rock scallop (Hinnites multirugosus) are described together with information on growth of juveniles and adults. Gravid individuals were collected from field populations throughout most of the year. These produced viable eggs when induced to spawn in the laboratory.

Larval development appeared normal over the range 8–18°C (optimal for culture, 14–18°C). Acceptable growth and survival were achieved on a mixed diet of Isochrysis, Monochrysis, Tetraselmis and Skeletonema. Metamorphosis began in larvae 200 μm in shell diameter (age, 3 weeks). Most rapidly growing post‐larvae reached 1.8 mm at two months (15–18°C).

Pre‐cementing juveniles held in cages in Mission Bay, San Diego, averaged approximately 8 mm/mo during summer (18–22°C) and half that rate throughout the rest of the year (13–18°C). Individuals 1.5 to 3.0 cm in October, 1975, reached shell diameters of 5.0 to 7.5 cm one year later.
AN ANALYSIS OF GRAVEL, PENS, CRAB TRAPS AND CURRENT BAFFLES AS PROTECTION FOR JUVENILE HARD CLAMS (Mercenaria mercenaria)1
Authors: Kraeuter John N. , Castagna Michael
Published: August 2010

The major hindrances to field grow‐out of juvenile hard clams (Mercenaria mercenaria) are wash by currents and predation. Previous data suggested that the effects of wind‐driven and tidal currents could be ameliorated by baffles and to some extent by pens and gravel. In our experiments predation protection was provided by gravel, pens and crab traps. Analysis of variance (ANOVA) was performed on quantitative samples of juvenile hard clams (2 mm seed) taken quarterly from field plots established in October 1975. All possible combinations of gravel, current baffles, pens and crab traps were examined. The results are interpreted as showing the varying seasonal effects of current action (storms) and predation on these newly planted and growing seed. The protection afforded by the combination of gravel and baffles was statistically superior to any of the individual or combined effects of the four variables for the first 11 months.

The method has the advantages of being simple and promises to be adaptable to infaunal species in wide variety of habitats with a minimum of modification.
AMMONIA TOXICITY IN CULTURED LARVAE OF THE AMERICAN LOBSTER (Homarus americanus)1
Authors: Delistraty Damon A. , Carlberg James M. , Van Olst Jon C. , Ford Richard F.
Published: August 2010

Ammonia is the chief nitrogenous excretory product of lobsters and is known to be toxic to these crustaceans at relatively low concentrations. The primary purpose of this study was to determine tolerance limits of larval Homarus americanus to ammonia in order to optimize design of the seawater circulation and waste treatment components of a lobster mariculture system. This is often a critical problem in culture systems in which a major part of the seawater is recycled.

The incipient median lethal concentration (LC50) and tentatively safe ammonia concentration were determined for fourth stage larvae of H. americanus to be 1.4 and 0.14 mg/liter un‐ionized ammonia‐nitrogen (NH3‐N), respectively.

The effects of pH, temperature, and salinity on ammonia toxicity also were evaluated. Increasing pH from 7.4 to 8.4 increases toxicity markedly. Increasing temperature from 21°C, near the optimum for growth, to 25°C increases toxicity only slightly. Changes in salinity from 31 to 36 ppt produce no appreciable effect. These increase in pH or temperature shift the NH3/NH+4equilibrium unfavorably toward the more toxic NH3negligible effect on the equilibrium.

A simplified steady‐state equation was developed for predicting the optimum biomass loading for a lobster culture system, based on the ammonia toxicity determined for fourth stage larval lobsters. This equation relates the ammonia tolerance limit, ammonia excretion rate, ambient ammonia concentration of the water source, water flow rate, degree of water reuse, and efficiency of ammonia removal. The time lag required for the culture system to attain steady‐state conditions also is considered.
DISEASONAL THERMAL AQUACULTURE— 1. EFFECT OF TEMPERATURE AND DISSOLVED OXYGEN ON SURVIVAL AND GROWTH OF Macrobrachium rosenbergii
Authors: Farmanfarmaian A. , Moore R.
Published: August 2010

Survival and growth of the giant shrimp (Macrobrachium rosenbergii) is profoundly influenced by changes in temperature and dissolved oxygen (Do) of thermal effluents from power plants which discharge into aquaculture systems. These changes are due to seasons as well as plant shutdown in areas such as the northeast United States. In laboratory studies simulating aquaculture ponds the Critical and Lethal Thermal Maximum (CTMax, LTMax) and Minimum (CTMin, LTMin) at high and low DO levels have been measured for shrimp pre‐acclimated to 20–36°C. CTMax and CTMin rise with temperature of acclimation. The same is true for LTMax and LTMin. Low DO reduces the upper temperature tolerance as shown by a drop in CTMax and LTMax. It can become a critical factor in ponds during the peak of the summer, especially at nights. By contrast, Do has little or no effect on CTMin and LTMin. Dissolved oxygen is not a limiting factor at low temperatures. Growth and Conversion Ratio were evaluated in chronic studies at various temperatures, DO being maintained at air saturation. Growth nearly doubled for every 5°C increase in temperature over the 20130°C range while there was no appreciable change in conversion ratio.
THE EFFECTS OF DELAYED FEEDING, STOCKING DENSITY, AND FOOD DENSITY ON SURVIVAL, GROWTH, AND PRODUCTION OF LARVAL RED DRUM (Sciaenops ocellata)
Authors: Roberts D. E. , Morey L. A. , Henderson G. E. , Halscott K. R.
Published: August 2010

The starvation time, optimal initial feeding time, stocking density, and food density were defined for larval red drum (Sciaenops ocellata) in 20‐ and 40‐liter tanks. When larvae were not offered food by the fourth day after eye pigmentation (fifth day from hatching), they experienced 100% mortality. The optimal initial feeding time for best survival (14%) was the second day after eye pigmentation. Growth and survival were affected by initial embryo stocking density and food density maintained in the tank. Stocking densities of 2, 10, and 20 embryos/liter and food densities of one, 5 and 10 rotifers/ml were tested in 40‐liter tanks. Survival and total biomass were higher when embryos were stocked at 10 embryos/liter and significantly higher when fed at 5 rotifers/ml. Growth was best when embryos were stocked at 2 embryos/ liter.
A STUDY OF THE EARLY LIFE STAGES OF THE LOBSTER, Homarus americanus, USING SCANNING ELECTRON MICROSCOPY (SEM)1
Authors: Heckmann R. A. , Infanger R. C. , Mickelsen R. W.
Published: August 2010

With the accelerated interest in commercial lobster production, knowledge of the early developmental stages is important. There are limited observations and data pertaining to the first 4 life stages of the American lobster Homarus americanus. The existing data can be strengthened through use of the scanning electron microscope. Current sketches are based on light microscopy and observations without magnification. A series of micrographs of the first 4 life stages with reference to existing drawings are presented. The first 3 larval stages float in the pelagic environment while the fourth stage sinks to the bottom and assumes the characteristic bottom‐dwelling behavior of adult lobsters. Characteristics pertaining to number and loss of appendages, size and division of the body, spines, division of the uropod, development of the walking legs and antennae are stressed. A two‐dimensional drawing will be presented utilizing the existing published data for the life stages and the scanning electron micrographs.
PROGRESS AND PROBLEMS IN LOBSTER BROODSTOCK DEVELOPMENT
Authors: Hedgecock D. , Moffett W. L. , Borgeson W. , Nelson K.
Published: August 2010

A major impediment to commercial farming of the lobsterHomarusis lack of control over reproduction. Without it, a steady supply of seed cannot be insured, nor can selective breeding be applied. The major block in the reproduction of either laboratory‐mated or wild‐caught inseminated females has been low frequency of egg extrusion. Prior to 1976, 5 extrusions were documented at the Bodega Marine Laboratory. Only one of these hatched successfully. Since late 1976, however, 10 females mated in the laboratory and 8 females inseminated in nature have successfully extruded. Of these ovigerous females, 5 hatched viable progenies and the remainder subsequently lost their eggs.

Most of these reproductive events occurred during a 22‐week experiment in which laboratory‐mated and field‐inseminated females were held in large tanks (37 cm × 74 cm × 49 cm deep) in a 3 temperature × 2 photoperiod design. Mortality was highest (5/18 or 28%) in the highest temperature schedule (18–22°C), lower (3/36 or 8%) in the middle temperature schedule (14–18°C) and zero (0/18) at lower temperatures (10–15°C). Molting followed a similar ordering, 67% at high temperatures, 64% at medium temperatures and 50% at low temperatures. The rate of extrusion showed an inverse pattern with only 6% in the high, 14% in the medium and 22% in the low temperature schedules. Photoperiod had an apparent effect only in the low temperature schedule with 2 molts in the short day and 7 in the long day cycle. Ovarian maturation was monitored during the experiment by a candling technique. Candling scores are correlated with actual ovary appearance and weight for 35 females sacrificed at the study's conclusion.

Progress in broodstock development has come chiefly through better husbandry (larger tanks, varied diet, as well as improved sampling techniques and record keeping practices), and in part through the success ofH. gammarusfemales in crosses toH. americanusmales. Two overall results of significance to lobster broodstock development are the evidence of shorter than 2‐year cycles in some females, and the lack of marked seasonality in reproductive activity. Two problems, in addition to understanding the complex interplay of molting and ovarian development, are shell disease and loss of eggs following extrusion.
CONVENTIONAL AND EXPERIMENTAL APPROACHES TO HYBRIDIZATION AND INBREEDING RESEARCH IN THE OYSTER
Authors: Stiles S.
Published: August 2010

Experimental manipulation of oyster eggs and cleavages is being used to support conventional research on inbreeding and hybridization. Twelve crosses of foundation stock in the commercial American oyster (Crassostrea virginica) were made to establish traditional full‐sib lines. In an experimental approach to producing inbreds some parthenogenesis was observed in eggs stimulated with spawned oyster sperm that had been X‐irradiated at doses ranging from 10,000 R to 225,000 R. Geographic and interspecific hybrid crosses with C. virginica have been made. The performance of hybrid larvae stressed with abnormally high and low temperatures was tested. Generally, there was better survival and growth of C. virginica geographic hybrids than of interspecific hybrids with C. gigas. Overall, however, there was better survival and growth of local controls in both experimental hybrid crosses and those crosses made specifically for testing the response of larvae to stress. Cytogenetic data suggested normal fertilization and meiosis in these hybrid crosses. The feasibility of controlling mass fertilization by temporarily inhibiting fertilization in spawning groups intended for hybridization was investigated using EDTA.
BACTERIAL DISINFECTION IN SHELLFISH HATCHERY DISEASE CONTROL
Authors: Blogoslawski W. J. , Stewart M. E. , Rhodes E. W.
Published: August 2010

Control of disease in shellfish culture is a complex and pervasive problem which can cause extensive loss of time, money, and efficiency. Many shellfish diseases are caused by pathogenic bacteria introduced into the hatchery system through a contaminated water source, an infected animal from natural waters, or a tainted food supply. It is the intent of this paper to explore 4 methods of bacterial disinfection in shellfish hatcheries: ultraviolet light treatment of bacterial shellfish pathogens, the addition of silver (AgNO3) to shellfish larval culture waters, ozone disinfection of contaminated culture water, and standard antibiotic treatment (neomycin) in shellfish hatchery disease control. The efficacy of each system is examined and recommendations are made for the incorporation of standard disease prevention methods in shellfish hatchery operations.
CRAWFISH POPULATION DYNAMICS AS THEY AFFECT PRODUCTION IN SEVERAL SMALL, OPEN COMMERCIAL CRAWFISH PONDS IN LOUISIANA
Authors: Huner J. V.
Published: August 2010

Crawfish population dynamics, as they affect production, were investigated for 1‐1/2 seasons, February 1976‐June/August 1976 and September/November‐June 1977 in 3 small, open commercial crawfish ponds. One pond (Boyce Pond), 0.5 ha, had a cover crop of rice preceding season 1 but was not drained and replanted between seasons (normal practice). The other 2 ponds (McCahill Ponds 1 and 2), 2 ha and 1 ha, were located adjacent to each other, shared the same water source, and had a cover crop of annual grasses and perennial, semi‐aquatic forbs. They were drained during the summers preceding seasons 1 and 2.

Crawfish populations were monospecific, Procambarus clarkii (Girard, 1852). There appeared to be a minimum of 3 significant waves of recruitment of young‐of‐the‐year during the September‐January period of each season in all ponds and a somewhat subdued wave in May. Crawfish became fully vulnerable to trapping (1.9 cm mesh) at 8.0–9.0 cm total length. Survival rates of such crawfish in 0.5 cm size classes ranged from 0.53‐0.62. Survival rates for crawfish less than 8.0 cm total length in 1.0 cm size classes were 0.67‐0.74. The majority of all crawfish matured in May of both seasons. Sex ratios were approximately 1:l.

Production for the Royce Pond was 4497 kg/ha in season 1 and 790 kg/ha in season 2. Combined production in the McCahill ponds was 1179 kg/ha in season 1 and 926 kg/ha in season 2. Factors affecting productions are discussed.

Length/frequency tables could be used to follow growth and predict the onset of Maximum Sustained Trapping Success (MSTS). Temperature appeared to exert a strong control over growth, hence onset of MSTS. During season 1, winter temperatures were mild (ll‐13°C) and MSTS began in early March. In season 2 when water temperatures were severe (4–7°C), USTS was delayed 4 weeks.
THE USE OF Artemia CYSTS IN AQUACULTURE: THE CONCEPT OF “HATCHING EFFICIENCY” AND DESCRIPTION OF A NEW METHOD FOR CYST PROCESSING
Authors: Sorgeloos P. , Persoone G. , Baeza‐Mesa M. , Bossuyt E. , Bruggeman E.
Published: August 2010

The quality of brands of Artemia cysts should be expressed on a weight basis, namely the number of live nauplii hatching out per unit of weight of product and not as a “hatching percentage” since the latter concept does not take into account the degree of impurity of the material. A standardized method for the determination of the hatching efficiency is proposed. A new methodology for cyst processing has been worked out at laboratory scale, based on a 2‐step cleaning (brine and tap water) followed by dehydration (air or brine) or decapsulation and dehydration (brine).
THE DESIGN AND DEVELOPMENT OF A FOULING RESISTANT MARINE FISH CAGE SYSTEM
Authors: Ansuini F. J. , Huguenin J. E.
Published: August 2010

A prototype low‐maintenance modular marine cage‐culture system for commercial use has been developed and is presently in service at Maine Salmon Farms, Wiscasset, Maine. The basic component of the cage system is a 1 times 3 m fiberglass frame covered with 90/10 copper‐nickel expandedmetal mesh of 76% open area. These panels are interconnected along with other fiberglass structurals, fittings and modular float units to form a 57 m3 rigid, floating cage system. The modular design allows this concept to be readily adapted to larger size floating cages, as well as submerged or bottom mounted applications. The excellent engineering properties of 90/10 copper‐nickel, coupled with its inherent resistance to biofouling, are the keys to the projected long, useful service life and low maintenance requirements. Design details, performance specifications and economic analysis, for both the prototype and larger future nested commercial systems, are provided.
DESIGN AND TEST OPERATION OF AN INTENSIVE CONTROLLED‐ENVIRONMENT OYSTER PRODUCTION SYSTEM
Authors: Thielker Jeffrey L.
Published: August 2010

A prototype oyster production system with a 10‐bushel design capacity has been operating for 6 months in order to demonstrate and document a number of the research‐derived design concepts and operating specifications. This is a technical demonstration project intended to maximize production rates in an intensive, controlled‐environment culture system. The unit functions as a working model yielding quantitative information concerning component and biological performance, material flow, and cost‐related material, energy and labor efficiencies over the long‐term production cycle.

The system is comprised of three integrated subsystems: 1) oyster life‐support, 2) algal production, and 3) water and waste handling. The design specifications and the degree of control provided are intended to maximize productivity and efficiency in each subsystem. Integration of the three subsystems involves recycling water (˜77%) without detriment to performance efficiencies.

Operation and evaluation of the system have supported some of the original premises. However, such analyses and concurrent experimentation have led to modifications in the system design, and in process procedures. The changes have reflected trade‐off decisions (for example, sacrificing production rates for economic and management considerations) and efforts to enhance productivity.
BIOECONOMIC MODELING WITH STOCHASTIC ELEMENTS IN SHRIMP CULTURE
Authors: Griffin Wade L. , Johns Michael A. , Hanson Jerrell S. , Brick Robert W.
Published: August 2010

The results of this study include the incorporation of water quality parameters and a growth function into a bioeconomic model of shrimp culture. Since the level of various parameters is unpredictable for future years (i.e., weather, ponds experiencing low oxygen), randomization of these parameters was introduced into the model. The results consist of a mean and standard deviation of profit determined from 25 replications of the model. The baseline model indicates that a mean profit of $679 per hectare would be achieved with only a 5% chance of a loss. Sensitivity tests of profit in the model, consisting primarily of changes in biological and environmental parameters, illustrate the usefulness of the model in directing future research.
FOOD AND FEEDING STRATEGIES IN CULTURE OF LARVAL AND EARLY JUVENILE PURPLE‐HINGE ROCK SCALLOPS, Hinnites multirugosus (GALE)
Authors: Cary S. C. , Leighton D. L. , Phleger C. F.
Published: August 2010

The purple‐hinge rock scallop is receiving increasing interest as a candidate for commercial mariculture. Hatchery culture of juveniles is prerequisite since natural recruitment of juveniles is variable and not dependable as a source of stock. Success in carrying larvae through metamorphosis has been limited. Critical to larval culture is a sound understanding of optimal food and feeding strategies.

Growth and survival were examined in early larvae fed six algal diets at four separate concentrations. The data clearly illustrate the superiority of both Isochrysis galbana and a Tahitian (T) strain of Isochrysis. Feed concentrations of 1 × 105 cells/ml were found to be optimal for these species of Isochrysis. An I. galbana diet supported 80% survival through metamorphosis. The other algae examined included Mono‐chrysis lutheri, Rhodomonas sp., Carteria pallida, and a 1:1:1 mixture of Rhodomonas, Monochrysis, and Isochrysis. All these diets supported 5–6% survival, and the growth was only slightly better than starvation controls.

A similar study was done with early juveniles (1 mm dia). The diets included: I. galbana, M. lutheri, Thalassiosira pseudonana (3H), T‐Isochrysis sp., and Phaedactylum tricornutum. As with the larvae, superior growth and survival occurred with diets of both species of Isochrysis. Cell concentrations between 1 × 105 and 2 × 105 cells/ml were optimal. The other diets supported minimal growth. In the feeding runs of both larvae and early juveniles, cell densities in excess of 5 × 105 cells/ml were detrimental.
ACCELERATION OF DEVELOPMENT AND GROWTH IN YOUNG GREEN ABALONE (Haliotis fulgens) USING WARMED EFFLUENT SEAWATER
Authors: Leighton David L. , Byhower Martin J. , Kelly Joseph C. , Hooker G. Neal , Morse Daniel E.
Published: August 2010

Larvae and juveniles of the green abalone grow and survive well at temperatures in the range 20–28°C. A program of hatchery research with this species utilizing thermal effluent has been in progress since 1979 at the Redondo Beach Electric Power Facility, Southern California Edison Company. All life stages may be cultured in the effluent seawater with temperature regulation by admixture of ambient seawater when required. Using thermal effluent, growth rates of juveniles are increased by a factor of 1.5–2.0 over those reared at ambient temperatures (14–20°C) characteristic of southern California. The time to harvest for seed 1–2 cm is reduced from about one year to six months.

While optimal temperatures for larvae and postlarvae fall in the range 20–24°C, juveniles are more broadly tolerant of heat and exhibit a growth optimum in the range 24–28°C. The upper lethal limit for juveniles is 31.5°C (LD50, 48 hours). Postlarvae, juveniles and adults have exhibited no indications of unfavorable conditions in power plant effluent.

Young adults at 1.5 years (4–5 cm) became reproductively mature and yielded viable larvae. Both hatchery‐reared and wild‐caught adult green abalone were conditioned to spawning readiness during winter months (natural period, spring‐fall) when held in a mixture of effluent and ambient seawater at 20–24°C.

Progeny from this research were provided to the California Department of Fish and Game for release in experimental plants. Approximately 30,000 juveniles were produced in 1980–81.
EXPERIMENTAL CULTURE OF THE OCEAN QUAHOG, Arctica islandica
Authors: Lutz Richard A. , Goodsell Joy G. , Mann Roger , Castagna Michael
Published: August 2010

Larvae and early postlarvae of the ocean quahog, Arctica islandica, were reared under experimental hatchery conditions. Mature eggs were stripped from ripe adults and exposed to a dilute solution of ammonium hydroxide for various lengths of time prior to addition of stripped sperm. The larval clams were reared through settlement and metamorphosis using the Wells‐Glancy (centrifuged, incubated seawater) method of algal culture and/or modifications of standard hatchery techniques developed by Loosanoff and Davis. Experimental cultures were maintained at various temperatures ranging from 8.5° to 14.5°C. At temperatures of approximately 13°C, the minimum time to settlement was 32 days, while settlement was not observed in a culture maintained between 8.5° and 10.0°C until approximately 55 days after fertilization. Larval growth rates were significantly lower in the culture maintained at 8.5–10.0°C than in cultures maintained at 11.0–14.5°C. An optical micrograph sequence of larval stages from the straight‐hinge stage through metamorphosis is presented to facilitate identification of Arctica islandica specimens isolated from plankton samples. While various workers have reported exceedingly low growth rates of juvenile and adult Arctica, growth rates of larval Arctica appear to be fairly “typical” of rates encountered within the class Bivalvia.
DECREASED TOXICITY OF COPPER AND MANGANESE IONS TO SHRIMP NAUPLII (Penaeus stylirostris STIMPSON) IN THE PRESENCE OF EDTA
Authors: Lawrence Addison L. , Fox Joe , Castille Frank L.
Published: August 2010

Although ethylenediaminetetraacetic acid (EDTA) is used routinely in the intensive culture of penaeid shrimp larvae to increase both the percentage of eggs that hatch and the survival of larvae, the mode of action is not known. To explain EDTA's beneficial effect this study compares the toxicities of copper and manganese divalent ions in the presence and absence of 10 mg EDTA/liter seawater. Toxicity was evaluated in terms of the percentage of Penaeus stylirostris nauplii surviving after 12 and 24 hours of exposure to either copper or manganese and in terms of the percentage of nauplii that metamorphose to the protozoeal stage.

In the absence of EDTA, copper and manganese ions were toxic to nauplii with copper causing 100% mortality at a much lower concentration (20 μM) than manganese (20,000 μM). In the presence of EDTA, survival of nauplii exposed to copper was increased but survival of nauplii exposed to manganese was not affected.

At concentrations lower than the levels that reduce survival, copper ions (0.2 μM) and manganese ions (2 μM) reduce the percentage of nauplii that metamorphose to protozoea. In the presence of EDTA, the percentage of nauplii that metamorphose to protozoea is increased with both nauplii exposed to copper ions and nauplii exposed to manganese ions.

The beneficial effects of EDTA are probably due to the chelation of copper and manganese ions by EDTA. Chelation lowers the free concentration of these ions and thus reduces their toxicities.
INTERNATIONAL STUDY ON Artemia:1 XXI. INVESTIGATIONS INTO WHY SOME STRAINS OF Artemia ARE BETTER FOOD SOURCES THAN OTHERS. FURTHER NUTRITIONAL WORK WITH LARVAE OF THE MUD CRAB, Rhithropanopeus harrisii
Authors: Johns D. Michael , Berry Walter J. , McLean Scott
Published: August 2010

In a series of studies conducted by members of the International Study on Artemia, differences in nutritional quality were documented between geographical strains of the brine shrimp Artemia. Concomitant with, and possibly related to nutritional effectiveness are differences in biometric traits and biochemical composition. Since these initial experiments could only hint at causal relationships, a series of experiments were carried out to further our understanding of cause and effect.

In one experiment we tried to ascertain whether the factors responsible for poor survival in larvae fed some brine shrimp strains are cumulative throughout larval development or whether there are critical periods when larvae are more sensitive. Our results indicate that the factors contributing to poor growth and survival are cumulative.

In a second experiment, we contaminated Brazil Artemia with diel‐drin, chlordane and combinations of the two and fed them to mud crab (Rhithropanopeus harrisii) larvae. The levels of contamination were chosen to approximate those suspected of contributing to the poor food value of some brine shrimp strains. In this experiment, however, diel‐drin and chlordane contamination appeared to have no effect on growth and survival of R. harrisii larvae.

In a third experiment, we fed Utah strain Artemia on Isochrysis galbana for 24 hours and then fed these brine shrimp to mud crab zoeae. Previous work had shown that this regime made Utah Artemia more suitable as a food source for a prawn. However, in our experiments, it did not improve survival of R. harrisii.
CULTURE TRIALS WITH ATLANTIC STURGEON, Acipenser oxyrhynchus, IN THE USA1
Authors: Smith Theodore I. J. , Dingley Edward K. , Marchette Donald E.
Published: August 2010

In South Carolina, a joint state‐federal program was initiated in 1977 to develop spawning and rearing techniques for Atlantic sturgeon, Acipenser oxyrhynchus, and to investigate its culture potential. Good progress has been made in developing the hatchery technology. Brood stock collection sites and techniques have been established and suitable transportation and holding procedures demonstrated for these large fish (˜ 40–100 kg). Homospecific hypophyseal injections were employed successfully to induce two spawnings. The artificially fertilized eggs, incubated in MacDonald hatching jars, hatched in about 120 hours at 17–18°C. Yolk sac was abosrbed by day 10 and the fry were weaned on a diet consisting of beef liver and salmon mash supplemented with live Artemia. During the second trial, fish hatched at 7.8 mm mean total length obtained a size of 176.7 mm in 204 days.

Several pond culture studies were undertaken with juvenile sturgeon. Although most fish eventually died (due to poor environmental conditions) some wild‐caught juveniles were successfully maintained under pond conditions for about 20 months and one brood female survived for 15 months. Pond‐held fish were fed trout chow supplemented with pieces of beef liver. Feeding activity could be observed at night along dike areas.
WEANING OF DOVER SOLE (Solea vulgaris) USING ARTIFICIAL DIETS
Authors: Metailler R. , Menu B. , Morinière P.
Published: August 2010

We conducted three experiments in which several types of weaning diets were compared using one‐month‐old soles which had been fed previously on living Artemia. The diets were: a) ground and frozen molluscs (Laevicardium crassum), b) dry pelleted diet stabilized with corn gluten (14%) including different attractive matter (ground polychaetes [Nephthys hombergii] or molluscs, 10% of the diet dry basis), c) the same dry pelleted diet lacking attractive matter, d) wet paste containing 50% of ground molluscs dry basis, and e) dry pelleted diet stabilized with 15% sodium algin.

Fish were examined after 55 days of feeding on the diets. In spite of large variability of growth, several facts were apparent. The presence of attractive matter seemed to enhance food intake and, consequently, growth. Concerning ground polychaetes, the attractant was found in the liquid phase after high speed centrifugation. Contrary to previous observations, frozen molluscs and wet paste containing ground molluscs did not give good results, especially for growth. The best results were obtained with dry artificial diet stabilized with algin. This seemed to be due to the high stability in water of the diet.

Weaning is an important step in the life of fishes and only a few of them can go through it with few difficulties. However, the growth of these latter fishes is similar to that of fish fed living prey.
POLYCULTURE OF CHANNEL CATFISH (Ictalurus punctatus) WITH ALL‐MALE TILAPIA HYBRID
Authors: Gabel Steven J. , Avault James W. , Romaire Robert P.
Published: August 2010

Channel catfish (Ictalurus punctatus) (x̄ = 0.8 g) and all‐male hybrid tilapia fingerlings (Sarotherodon mossambica ♂ × S. hornorum ♀) (x̄ = 35.0 g) were stocked in 0.04 ha replicated ponds in Baton Rouge, Louisiana, in March and July 1981, respectively. The ponds were stocked at densities of 11,110 catfish per ha, 11,110 catfish with 5,550 tilapia per ha, 7,400 catfish per ha, and 7,400 catfish with 3,700 tilapia per ha. The fish were fed daily at 4% of estimated catfish biomass and were harvested in November 1981.

There were no differences in dissolved oxygen or water temperature among the four culture systems (P > 0.05). The presence of tilapia, however, significantly increased water turbidity, pH and chlorophyll a concentrations (P < 0.05). Tilapia did not improve water quality and may have deteriorated it. Tilapia did not affect channel catfish growth or production (P > 0.05), but the presence of tilapia did significantly increase total fish yield (P < 0.05) by 13.5 and 32.2% at low and high catfish densities, respectively. Channel catfish and tilapia averaged 390 and 245 g at harvest, respectively. Overall catfish survival averaged 61%. Tilapia survival was 72% and 61% at low and high densities, respectively.
ALGAE AND DETRITAL MATTER AS FOOD FOR JUVENILE PURPLE‐HINGE ROCK SCALLOPS,Hinnites multirugosusGALE
Authors: Phleger C. F. , Cary S. C. , Leighton D. L.
Published: August 2010

Feeding experiments using commonly‐cultured algae were conducted with purple‐hinge rock scallops,Hinnites multirugosusGale, to suggest the application of these algae to hatchery culture of scallops. The uptake of finely divided particulate matter was also studied to ascertain the possible importance of detritus as a supplemental food for the rock scallop.

A 1:1:1 mixture by culture volume of TahitianIsochrysis, Tetraselmis suecica, andDunaliella salinaappeared to be superior as a diet for juvenile rock scallops. Significant growth also occurred in juvenile rock scallops fedT‐Isochrysis, T. suecica, Isochrysis galbana, andRhodomonassp.Gymnodinium splendens, Monochrysis lutheri, andDunaliella salinafed alone were poor foods for juvenile rock scallops. Finely divided particulate matter as radiolabeled abalone fecal matter was utilized as food. Significant radioactivity appeared in DNA, RNA, lipid, protein, carbohydrate, and free‐reducing substances after one week providing evidence that particulate matter was incorporated into juvenile rock scallop metabolic pathways.
EPIZOOTIOLOGIC STUDY OF MID‐CYCLE DISEASE OF LARVAL Macrobrachium rosenbergii
Authors: Akita G. , Nakamura R. , Miyamoto G. , Brock J. , Fujimoto M. , Oishi F. , Onizuka D. , Sumikawa D.
Published: August 2010

Mid‐cycle disease (MCD) of larval Macrobrachium rosenbergii has reduced survival of larval cultures at the state facility from a normal 50–70% of the population at the post‐larval stage, to 5–10%. Observations revealed a characteristic mortality pattern, where a peak in daily mortality occurred near the middle of the rearing cycle.

Epizootiologic studies were initiated using existing facilities, to aid in characterization of MCD and elucidate possible causes. Experiments were undertaken in duplicate culture tanks, each separated into 4 equal volume compartments by nitex screen. Water, algae, and some feed could pass between compartments; prawn larvae could not.

“Reference” larvae were introduced into a compartment of each tank on the day of hatch. “Test” larvae populations of different ages and sources were introduced into the remaining compartments at various times after the initiation of the experiment. Dead larvae in the bottom sediment were counted daily and mortality curves generated. Length and developmental stage of live and dead animals in each compartment were assessed daily.

Results indicated that a “toxic period” of unknown etiology began on the 10th day of culture and probably extended for the duration of the rearing cycle. “Test” populations introduced during the “toxic period” displayed a mortality peak within 4–6 days. Larvae at age 15 days (stage 6–7) or older appeared refractory to the “toxicity.”

MCD apparently reduced growth rates (length) but did not appear to selectively kill larger, faster growing, susceptible individuals. Problematically large portions of animals lost from populations were not accounted for. Studies on MCD will continue.
THE EFFECTS OF EDTA (ETHYLENEDINITROTETRAACETIC ACID) ON THE SURVIVAL AND DEVELOPMENT OF SHRIMP NAUPLII (Penaeus stylirostris STIMPSON) AND THE INTERACTIONS OF EDTA WITH THE TOXICITIES OF CADMIUM, CALCIUM, AND PHENOL
Authors: Castille Frank L. , Lawrence Addison L.
Published: August 2010

To examine the hypothesis that EDTA increases hatching rates and survival of penaeid shrimp larvae by decreasing the toxicities of heavy metals through chelation, the toxicity of cadmium, a highly toxic metal, was compared to the toxicities of calcium and phenol in both the presence and absence of EDTA. In addition, the toxicity of EDTA at higher concentrations was examined.

The toxicities of EDTA, cadmium, calcium, and phenol were evaluated in terms of the percentage of nauplii surviving after 24 hours of exposure and the percentage of nauplii which metamorphosed to protozoea. The toxicities of cadmium, calcium, and phenol were also determined in the presence of EDTA.

EDTA concentrations of 1.34 mM were lethal to nauplii. At 0.67 mM, EDTA reduced the percentage of nauplii which metamorphosed to protozoea but below 0.3 mM neither survival nor metamorphosis were affected.

Cadmium, phenol, and calcium were lethal to nauplii at concentrations of 20 μM, 7 mM, and 400 mM, respectively. Metamorphosis was blocked by concentrations of 1 μM, 0.9 mM, and 200 mM, respectively. However, in the presence of 0.3 mM EDTA, the toxicities of cadmium and calcium were reduced. Cadmium concentrations of 20 μM did not affect either survival or metamorphosis in the presence of EDTA. In calcium concentrations of 50 and 100 mM, the percentage of nauplii that metamorphosed to protozoea was increased by the addition of EDTA. The interaction of EDTA and phenol toxicity was not significant.
A COMPARISON OF TWO PRAWN (Penaeus monodon) BROOD STOCK SYSTEMS—LAND‐BASED TANKS AND MARINE PENS1
Authors: Primavera J. H. , Gabasa P.
Published: August 2010

The paper compares two prawn (Penaeus monodon) brood stock systems—land‐based tanks and marine offshore pens. Construction costs and annual maintenance and operating costs total US$1,430 and $2,550 for the tank and $1,500 and $3,680, respectively, for the pen. The 12 m3 ferrocement tank requires power for a 24‐hour seawater flowthrough and can stock 50 animals/run for a projected yearly production of 8×106 nauplii for 1.2 × 106 juveniles (0.1 to 0.5 g body weight). The 16×16×4 m pen made of bamboo and nylon net materials can accommodate 300 brood stock/run with a projected annual production of 30 × 106 nauplii or 4.5 × 106 juveniles. Discussion includes general requirements, mortality and maturation rates, and criteria for choosing a brood stock system.
REPORT ON PENAEID SHRIMP CULTURE CONSULTATION AND VISIT, GUAYAQUIL, ECUADOR, SOUTH AMERICA, AND PANAMA, CENTRAL AMERICA, AUGUST 12 TO SEPTEMBER 20, 19811
Authors: Mock C. R.
Published: August 2010

The culture of penaeid shrimp in grow‐ponds in Ecuador is expandin: at a rapid rate. Coastal, low lying, salt flats adjacent to estuarine waters, unsuited for classical agriculture, are being transformed into productive shrimp farming areas. Currently, post‐larval “seed” shrimp must be collected from the wild to stock the ponds. The Ecuadorian Government is concerned, however, that this practice may affect production from the trawl fishery.

A hatchery facility with the capacity of producing 5 million postlarval shrimp per month is planned by the Ecuadorian government. This should help eliminate part of the demand for post‐larval shrimp from the wild stock. Also, an extension service is being developed to aid the shrimp farmers.

An on‐site visit and description of Ralston Purina's hatchery facilities in Panama, Central America, is also included.
BREEDING AND CULTURE OF THE RED‐GOLD COLOR PHASE OF TILAPIA
Authors: Behrends L. L. , Nelson R. G. , Smitherman R. O. , Stone N. M.
Published: August 2010

The red‐gold tilapia, a color phase resulting from crossing a mutant “reddish‐orange” color strain of Tilapia mossambica with “normal” colored tilapia species, is cultured on a limited basis in Asia, the Mideast, Latin America, and the United States. Marketing surveys have shown a significant consumer preference for the red‐gold color phase, presumably due to their similar appearance to popular reef and marine fish. Studies have been initiated between the Tennessee Valley Authority and Auburn University to define the culture and breeding characteristics of the red‐gold tilapia. Yield trials have been conducted in fertilized ponds and in cages receiving feed. Growth rates for young‐of‐the‐year and overwintered fingerlings have been quantified for males and females. Hormone‐induced sex reversal has shown potential for reducing reproduction in culture ponds. Results from F‐1 and F‐2 inbreeding studies suggest that 2 to 3 genes influence the gold coloration. To date, 6 different phenotypes (gold, bronze, pink‐mottled, pink, white, and wild) have been described.