bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

ABSTRACTAmmonia 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

AbstractSurvival 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

AbstractThe 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

AbstractWith 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

AbstractA 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

AbstractExperimental 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

AbstractControl 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

AbstractCrawfish 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

AbstractThe 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

AbstractA 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

AbstractA 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

AbstractThe 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

AbstractThe 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

AbstractLarvae 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

AbstractLarvae 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

AbstractAlthough 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.