bluuebunny/crossref_metadata_2025 huggingface dataset:
Normalization in cointegrated time series systems
Authors: Rossana Robert J.
Published: August 2010

Abstract A method for normalizing cointegrating vectors is proposed for cointegrated time series systems containing multiple cointegrating vectors, a method requiring that an identity matrix appear in the normalized cointegrating matrix with unit coefficients attached to the endogenous or choice variables. The preferred method causes the normalized cointegrating matrix and the adjustment matrix to be consistent with the implications of static and dynamic economic theory. Alternative normalizations generate cointegrating and adjustment matrices that do not match up well with economic theory and do not reveal the testable restrictions implied by static economic theory.
Does the version of the Penn World Tables matter? An analysis of the relationship between growth and volatility
Authors: Ponomareva Natalia , Katayama Hajime
Published: August 2010

AbstractThe Penn World Tables (PWT) are an important data source for cross‐country comparisons in economics. The PWT have undergone several revisions over time. This paper documents how countries' output growth rates change across four publicly available versions of the PWT. We show that for some countries the magnitude of the differences is significant and/or the sign of the growth rates changes across versions. Using as an exampleRamey and Ramey (1995), who found growth volatility has a significant negative effect on growth, we demonstrate that conclusions based on one version of the PWT may not hold under another version.
International corporate taxation and U.S. multinationals' behaviour: an integrated approach
Authors: Azémar Céline
Published: August 2010

Abstract This paper explores the effects of corporate taxation on U.S. capital invested abroad and on tax planning practices. The econometric analysis first indicates that investment is strongly influenced by average tax rates, with a magnified impact particularly for low‐tax rates, implying that the attractiveness of low‐tax countries is not weakened by anti‐deferral rules and cross‐crediting limitations. Further explorations suggest that firms report higher profit, higher Subpart F income, and are less likely to repatriate dividends when they are located in low‐tax jurisdictions. Finally, when the role of effective transfer pricing regulations is estimated, it appears that low degrees of law enforcement are associated with higher income shifting.
The evolution of male‐female earnings differentials in Canadian universities,1970–2001
Authors: Warman Casey , Woolley Frances , Worswick Christopher
Published: August 2010

Abstract The evolution of academic salaries and the gender earnings gap in Canadian universities is analysed using a unique Statistics Canada data set containing detailed information on all full‐time teachers at Canadian universities over the period 1970 through 2001. Male salaries declined across cohorts, while female salaries remained stable; consequently, male‐female earnings differentials have narrowed. Recent years have also seen increasing variation in academic salaries for both men and women. A gender earnings gap remains, the bulk of which can be explained by differences in men's and women's rank and field. The unexplained earnings gap has decreased over time.
Do trade missions increase trade?
Authors: Head Keith , Ries John
Published: August 2010

Abstract In an effort to stimulate trade, Canada has conducted regular trade missions starting in 1994, often led by the Prime Minister. According to the Canadian government, these missions generated tens of billions of dollars in new business deals. This paper uses bilateral trade data to assess this claim. We find that Canada exports and imports above‐normal amounts to the countries to which it sent trade missions. However, the missions do not seem to have caused an increase in trade. In the preferred specification, incorporating country‐pair fixed effects, trade missions have small, negative, and mainly insignificant effects.
Barriers to physical activity participation in older Tongan adults living in New Zealand
Authors: Kolt Gregory S , Paterson Janis E , Cheung Vivian Y M
Published: August 2010

Objectives:  To identify perceived barriers to physical activity participation in older Tongan adults living in New Zealand.

Methods:  Focus groups with 24 sedentary older Tongans to examine the role of physical activity in Tongan culture, perceived barriers to and benefits of physical activity participation, and how to encourage physical activity participation. Data were analysed using a descriptive qualitative methodology.

Results:  The perceived role of physical activity centred on traditional ways of living, recreational and outdoor pursuits, and house chores and activities of daily living. Physical activity barriers included education and motivation, physical environment, family environment, physical and health issues and cultural expectations. Social, psychological, cognitive and health benefits of physical activity were identified, and it was suggested that the government, medical/health practitioners and church leaders were all important in encouraging increased participation.

Conclusions:  Community‐based programmes may be one way of encouraging physical activity in this population.
FRESHWATER PRAWN FARMING IN TAIWAN—THE PATTERNS, PROBLEMS AND PROSPECTS1
Authors: Chao Nai‐Hsien
Published: August 2010

In Taiwan, large acreages of suitable freshwater ponds, streams and dams, as well as irrigation canals used for culturing various freshwater fishes, are available to shift to freshwater prawn farming because of its proven good flavor, higher price and the established propagation and cultivation techniques. Since 1974, the number of stockable juveniles supplied by Tungkang Marine Laboratory (TML) and some private hatcheries has increased year by year from 110,580 to over 5,000,000 in 1978. Therefore, several culture patterns have been set up as demonstrations in TML and in the private farms consulted by TML. Extensive and intensive culture, polyculture with fishes, as well as river ranching, are discussed. The bottom choice of mud pond, sand pond, cement pond, and polyethylene sheet pond, and the food choice, mainly of egg custard, steamed rice, fish paste in early culture stage, with trash fish, cereals and prepared feed in late culture stage are summarized. The marketing system is discussed and an estimation of total production is made on updated investigation. A speedy solving of the listed local problems would lead to steady progress in freshwater prawn farming.
THE ROLE OF NATURAL PRODUCTIVITY AND APPLIED FEEDS IN THE GROWTH OF Macrobrachium rosenbergii1
Authors: Stahl Margo S.
Published: August 2010

In Hawaii, applied feeds account for a high percentage of a prawn farmer' production costs. These applied feeds may be important not only because of direct consumption by prawns, but also because of entrance into the natural food chains, which appear to contribute significantly to prawn nutrition. This paper presents information evaluating the direct and indirect roles of an applied feed in a simulated pond environment as well as the relative contributions of the autotrophic and heterotrophic food chains to prawn growth.

Postlarval prawns were placed in large outdoor pools having various combinations of 3 potential food sources—organic detritus, phytoplankton, and applied feed. Results of two 50‐day unreplicated studies, with 3 treatments each, determined that natural foods alone, consisting primarily of a mixture of organic detritus and soil produced growth rates equal to or better than commercial production ponds. The applied feed alone (26% protein), with minimal natural foods and no organic detritus or soil, was unable to support growth rates comparable to the other treatments. The earthen substrate appears to supply a major growth factor lacking in applied feeds.

An applied feed to supplement the natural foods produced significantly better growth than that obtained by natural foods alone, although this increase was not dramatic. Growth rates in this system averaged 1.5 cm/mo. Water column phosphate levels as well as carbon and nitrogen levels in the sediment increased in the systems supplemented with feed.

Future pond management may require more attention to promoting natural productivity, particularly in the detrital layer. Complementary interaction is desirable between naturally available foods and applied feeds.
BIVALVE MOLLUSCAN CULTURE IN AN ARTIFICIAL UPWELLING SYSTEM1
Authors: Roels Oswald A. , Sunderlin Judith B. , Laurence Scott
Published: August 2010

Since May 1972, the St. Croix Artificial Upwelling Project has utilized a constant flow of nutrient‐rich water, pumped from 870 m depth in the sea into ponds (100 m2, one m deep) on the north shore of St. Crolx, to produce phytoplankton. This phytoplankton suspension was pumped continuously to filter‐feeding shellfish.

Initial technical feasibility experiments have demonstrated that Mercenaria campechiensis, a hybrid of M. mercenaria x M. campechiensis, Tapes japonica, Ostrea edulis, Crassostrea gigas, C. gigas Kumamoto variety, Argopecten irradians and Pinctada martensii grew rapidly in this system. Crassostrea virginica and M. mercenaria did not grow well.

From October 1976 until October 1978, the St. Croix Artificial Upwelling Mariculture system was operated in pilot‐plant fashion to determine yields and provide a basis for cost estimates of the system. Tapes japonica used in the pilot plant were produced in the hatchery of the Artificial Upwelling system in St. Croix. The phytoplankton protein production achieved in the pilot plant, including the down‐time of the nutrient‐limited pools for cleaning and reinoculation, was equivalent to 8.1 tons/ha/year from July 1977 until July 1978. During a 12‐month period of pilot plant operation (October 1977‐October 1978), 423 kg of Tapes japonica were produced, corresponding to 22% conversion efficiency of phytoplankton protein to shellfish meat protein and 42.3 tons of shellfish produced/year/ha of phytoplankton pond. An economic evaluation of the pilot plant results is underway.
ARTIFICIAL INCUBATION OF GREEN SEA TURTLE EGGS (Chelonia mydas)
Authors: Wood James R. , Wood Fern E.
Published: August 2010

Green sea turtle eggs obtained from both a captive breeding colony and natural beaches are artificially incubated at a commercial sea turtle farm in the Cayman Islands, British West Indies. Eggs are commonly incubated in styrofoam boxes packed with sand and eggs. Experiments involving variations of packing procedures, egg handling, temperature control and hatchery conditions have been done to verify the optimum incubation methods and conditions. Results clarify the need for maintaining appropriate temperature and adequate oxygen levels to assure the maximum yield from eggs incubated.
INTRODUCTION TO AQUACULTURE IN TAIWAN1
Authors: Li Yenpin , Liao I‐Chiu
Published: August 2010

Taiwan is located in the subtropical region with the Tropic of Cancer crossing at mid‐island. The warm weather permits a growing season of 8–10 months for most warm water species. It is generally believed that aquaculture has been practiced in Taiwan for some 300 years. In 1977, the total pond area under aquaculture in Taiwan was 31,757 ha, including 13,460 ha of fresh water and 18,297 ha of brackish water. The area of reservoir and paddy field utilized for culture was 8,550 ha. In addition, there were 14,646 ha of shallow sea along the west coast of Taiwan and coastlines of Penghu (Pescadores) utilized for seaweed, oyster and clam culture. Total aquaculture production in 1977 was 139,628 metric tons, accounting for 16.3% of the year' total fishery production; of this, 61,285 metric tons were from freshwater ponds, 38,466 metric tons from brackish water ponds, 8,838 metric tons from reservoirs and paddy fields, and 31,039 metric tons from shallow sea culture.

The organisms under aquaculture include finfish, crustaceans, molluscs and seaweeds. However, limitations arising from scarcity of land available for conversion into aquafarms and water pollution problems have partially restricted expansion.

All aquaculture production in Taiwan has been achieved in the private sector largely by individual farmers and a small number of companies mostly involved in eel and shrimp culture enterprises. Research and extension services have been supported by the government. Emphases of aquaculture research have been on controlled reproduction, intensive culture systems and fish diseases. Technical advances have been made in the artificial propagation of major Chinese carp, grey mullet, penaeid shrimp, Macrobrachium, small abalone, etc., development of cage culture of fish, intensive culture of eel and shrimp, hanging method of oyster culture and production of tilapia. Among the top priority problems are unstable seed supply of some important species, i.e., milkfish and eel, and high level technology to increase aquaculture operation per unit area.
PROGRESS AND PROBLEMS OF NETCAGE CULTURE OF GROUPER (Epinephelus tauvina F) IN SINGAPORE
Authors: Chen F. Y.
Published: August 2010

The development of netcage culture of grouper (Epinephelus tauvina) and other expensive fish species in Singapore, a densely populated island state with inherent physcial limitation, is aimed at maximizing production and economic returns per unit area or effort. Studies on netcage culture are conducted at the floating experimental fishfarm. The floating structure with 32 cage units, and its effect on current movement are described. Cost‐benefit analysis based on a production of 40 kg/m2/year demonstrates the economic viability of grouper culture in Singapore. Large‐scale production is, however, hampered by a shortage of fingerlings and feeds (trash fish).

Scientific breakthrough on the breeding of the protogynous hermaphrodite has been achieved in early 1977. It is largely due to the success in inducing sex inversion of adult females to functional males. Technical details and problems of induced sex inversion, spawning and larval rearing are discussed at length. Research into substituting trash fish with dry pelleted feeds in the weaning of juveniles is encouraging. This is discussed briefly together with the diseases encountered.
PROSPECTS FOR COMMERCIAL CULTURE OF THE EUROPEAN SEA BASS (Dicentrarchus labrax) AND OTHER MARINE FINFISH IN FRANCE AND NEIGHBORING COUNTRIES
Authors: Girin Michel
Published: August 2010

The author summarizes the work carried out in France and neighboring countries, for the last decade, on cultivation of European sea bass (Dicentrarchus labrax), gilthead sea bream (Sparus auratus), grey mullet (Mugil cephalus), Dover sole (Solea solea) and turbot (Scophthalmus maximus).

Particular emphasis is given to the European sea bass, a carnivorous fish whose market value ranges between 6 and 10 $US/kg. Among the species listed, it is the only one presently cultured from egg to pansize fish in commercial ventures. Although economic aspects are not completely known, several large‐scale hatcheries and demonstration farms are under construction. Many others are planned for the near future.
EFFECTS OF PHOTOPERIOD AND TEMPERATURE ON THE SPAWNING OF YELLOW PERCH (Perca flavescens)1
Authors: Kayes Terrence B. , Calbert H. E.
Published: August 2010

The yellow perch (Perca flavescens) in Lake Mendota, Dane County, Wisconsin, normally spawn over a 2‐ to 3‐week period in April to early May when the water temperature reaches 8.0 to 12.0°C. Adult fish captured and warmed from 2.5 to 9.0–13.0°C in February began spawning in the laboratory within the same 4‐day period in April as did the fish in Lake Mendota. This was true regardless of whether the perch in the laboratory were under a 13.5‐hour light (L)/10.5‐hour dark (D) or a 10.5 L/13.5 D photoperiod. The spawning season in the laboratory, however, lasted 2 weeks longer than it did in the field. Perch captured in April spawned readily (within 7 days) in tanks under a 13.5 L/10.5 D photoperiod when the temperature was raised from 5.0 to 12.0°C. Perch also spawned under photoperiods of 18 L/6 D and 6 L/18 D when warmed from 5.0 to 12.0°C, but the predictability of spawning was decreased. Keeping fish at 5.0°C slowed but did not entirely prevent the onset of spawning. In separate tests, the proportion of females that spawned within 7 days of a 5.0 to 12.0°C temperature shift increased as the spawning season progressed. It is concluded that the onset of spawning in yellow perch depends more on the intrinsic maturational state of the gonads than on specific spring‐time photoperiod‐temperature cues. Temperature may exert a major influence on maturation and seems to have a modulating influence on spawning. However, rising temperature and/or temperature thresholds per se do not determine when perch spawning begins. Photoperiod may also have a modulating influence on spawning, but one that is not as important as that of temperature.
MATURATION OF PENAEID SHRIMP: DIETARY FATTY ACIDS
Authors: Middleditch B. S. , Missler S. R. , Ward D. G. , McVey J. B. , Brown A. , Lawrence A. L.
Published: August 2010

Comparisons were made between fatty acid profiles of gonad, digestive gland, and tail muscle samples of immature and mature male and female Penaeid shrimp obtained at sea. The major fatty acids of the lipids from mature ovaries were C20 and C22 polyunsaturated fatty acids. An annelid rich in lipids containing these acids was used as a dietary supplement for shrimp grown in the laboratory, and spawning was achieved with Penaeus setiferus. The possible role of polyunsaturated fatty acids in ovarian maturation is discussed.
CONDITIONS FOR HOLDING AND PROPAGATING CRAWFISH BROOD STOCK (Procambarus clarkii)
Authors: Nelson Robert G. , Dendy J. S.
Published: August 2010

Commercial producers of the red swamp crawfish (Procambarus clarkii) require a source of stock other than from the wild in order to supplement natural pond production, extend the growing season, and improve genetic characteristics. Thus, consideration is given to systems for holding and propagating brood stock. Physical and chemical conditions of importance for holding environments include size and shape of container, water depth, surface area, shelters, water hardness, and dissolved oxygen content. Biological influences of importance include density, cannibalism, predation, parasitism, and nutrition. Methods for spawning, hatching, and rearing of young are described.
ASSORBIC ACID: NUTRITIONAL REQUIREMENT AND ROLE IN WOUND REPAIR IN PENAEID SHRIMP
Authors: Lightner D. V. , Hunter B. , Magarelli P. C. , Colvin L. B.
Published: August 2010

Ascorbic acid (AsA) has been identified as a dietary requirement for cultured juvenile penaeid shrimp (Penaeus californiensis and Penaeus stylirostris). A dietary intake of 0.1% was sufficient to prevent nutrition‐related deaths among these shrimp. Without sufficient dietary AsA, a deficiency death, Black Death, occurred. This disease is characterized by melanized hemocytic lesions distributed throughout the collagenous tissues of the shrimp' body. The specific requirement for AsA was demonstrated by feeding a special AsA supplement which resulted in the cessation of Black Death among an AsA‐deficient population. Normal collagen metabolism and wound repair in two penaeid shrimp (Penaeus californiensis and Penaeus stylirostris) was shown to be dependent upon ascorbic acid (AsA) nutrition. A significantly greater number of mortalities occurred among wounded AsA‐deficient shrimp of both species due to poor wound repair than among wounded controls.
IMMUNIZATION OF FISHES IN WORLD MARICULTURE: A REVIEW
Authors: Harrell Lee W.
Published: August 2010

The capability to mount an immune response against pathogens has been recognized in fish since rainbow trout (Salmo gairdneri) were successfully vaccinated against the bacterial disease furunculosis in 1942. Most investigations into the development of fish vaccines since that time have focused on the bacterial pathogens of salmonids.

The majority of research and development of practical vaccines for cultured fish has been realized in the past 10 years and presently the field of fish immunology is enjoying a rapid and productive growth. Interest in fish from a phylogenetic or comparative aspect led many competent individuals and institutions to explore the nature and mechanisms of the immune response in several species. Knowledge gained from these investigations has been the foundation for work on practical vaccine development.

During the early 1970′ in the Pacific Northwest, commercial growers hand vaccinated marine cultured Pacific salmon against vibriosis. Hundreds of thousands of juvenile salmon were individually injected using automatic syringes and assembly line techniques. With the advent of large‐scale aquaculture operations, the necessity for an efficacious delivery system for large numbers of fish became evident. Recently, new methods and novel techniques such as immersion and spray vaccination have been developed by private, academic, and governmental agencies.

A review is given of the evolution of vaccines and vaccine delivery systems in cultured finfish.
ABOUT THE CONCEPT OF CROWDING DISEASE AND SANITARY LOT IN MODERN INTENSIVE AQUACULTURE: A SHORT NOTE
Authors: AQUACOP
Published: August 2010

Most of the diseases that occurred in modern intensive aquaculture are due to opportunistic pathogens and can be considered as crowding diseases. The application of the sanitary lot technique would greatly reduce the spread of such diseases.
A RADIOGRAPHIC STUDY OF THE LOBSTER (Homarus americanus) ALIMENTARY CANAL
Authors: Bayer Robert C. , Gallagher Margie Lee , Leavitt Dale F. , Rittenburg James H.
Published: August 2010

Adult lobsters (Homarus americanus) were administered barium sulfate orally and examined by fluoroscopy and conventional X‐ray techniques. Barium sulfate was observed outlining the cardiac and pyloric stomach intestine and cecum. Barium sulfate, which has a particle size of one micron, was rarely observed within the midgut gland. This probably indicated that the pyloric stomach functions as a particle filter allowing small digesta particles and solubles to move into the tubules for absorption to occur. When barium was observed in the midgut gland it was probably the result of prolonged micropulverizing of the ingesta by the gastric mill to a size that is filterable by the stomach. The stomach was observed releasing ingesta into the small intestine in pulses. Peristaltic movement was observed in the small intestine. The small particle size of one micron which would not pass into the tubules supplies evidence that particle size may be an important factor in diets that are designed for efficient utilization.
FROM A HATCHERY…LIGHTLY
Authors: Henderson Stephen P.
Published: August 2010

Much attention has been given to recent advances in the art of bivalve molluscan mariculture arising from the contributions of private research groups, university programs, government agencies and commercial enterprises. The state‐of‐the‐art of bivalve culture is briefly explored here, areas of need are identified and these are then related to the capabilities and limitations of shellfish hatcheries. After differentiating the various types of hatcheries and describing their goals and capabilities, the author' company is used as a tool to illustrate and discuss the contributions which the industry can expect from commercial hatcheries and to identify those things which must be done by organizations other than hatcheries. In conclusion, the author perceives that real progress in the advancement of bivalve molluscan mariculture will occur only through the combined efforts of several groups and call for an enhanced coordination of effort.
BIVALVE MOLLUSCAN MARICULTURE: A Mytilus PERSPECTIVE
Authors: Lutz Richard A.
Published: August 2010

Continued growth in the demand for mussels (Mytilus edulis) in the United States will (in the near future) necessitate transforming conditions of supply based on wild harvest to conditions based on mariculture. Mussel cultivation presents an effective means of expanding the resource base, and the accelerated growth and superior quality of cultured mussels make this product an attractive addition to the industry. Experimental and pilot commercial mussel culture systems have been successful in various areas of the United States and continued expansion of mariculture operations offers the potential for a dependable commercial supply of high quality mussels. To enable production at a competitive cost, labor‐intensive processes, associated with various aspects of mussel mariculture, should be mechanized. Considerable research is required in order to obtain an adequate understanding of the manner in which biological and physical parameters will affect production efficiency of large‐scale commercial operations.
A NEW DRY DIET WITH ALTERNATIVE OIL SOURCES FOR PACIFIC SALMON
Authors: Hardy Ronald W. , Iwaoka Wayne T. , Brannon Ernest L.
Published: August 2010

A dry diet utilizing two oil sources that are less expensive and easier to obtain than marine fish oils was developed and found acceptable to salmon.

Chinook salmon fry (initial wt = 0.5 g) were fed the dry diet with either cod liver oil, linseed oil, or a linseed oil‐tallow mixture as the dietary oil source. A commercial moist pellet and a commercial dry pellet were also fed. Growth and feed conversions were monitored throughout the 12‐week experiment and the proximate composition of the fish were determined at the end of the experiment along with the fatty acid compositions of the diets and total body lipids of the fish.

Fish fed the experimental dry diets were significantly larger than those on the moist pellets. The commercial dry pellet was discontinued after six weeks due to poor growth. Among groups of fish fed the dry diet, those given the formulation containing cod liver oil were slightly heavier than those receiving either the linseed oil or linseed oil plus tallow formulations. Feed conversion was similar among fish fed the experimental dry diets and lower than the feed conversion of fish given the moist pellets.

Fish receiving the moist pellets had less carcass fat and more carcass protein than did fish on the experimental dry diets. The difference reflected the level of protein in the diets. The fatty acid composition of the total body lipids varied with the fatty acid composition of the diets.
THE EFFECT OF ANDROGENIC STEROIDS AS DIETARY ADDITIVES ON THE GROWTH OF CARP (Cyprinus carpio)
Authors: Matty A. J. , Lone Khalid P.
Published: August 2010

Naturally occurring androgenic steroids, testosterone, 11‐ketotestosterone and adrenosterone were incorporated into trout feed pellets and their effect on growth examined when each was fed to juvenile common carp (Cyprinus carpio). The steroids were administered for a period of 60 days at concentrations of 1.0, 2.5, 5.0 and 10 mg/kg of diet at a rate of 5% of body weight/day. After 60 days the drugs were withdrawn and fish returned to normal diet for another 30 days and growth monitored. Significant increases in body weight, total length and specific growth rate were recorded for all steroids. At the end of 60 days (drug feeding period) the fish receiving testosterone, 11‐ketotestosterone and adrenosterone were 84.2%, 92.7% and 115.9% respectively, heavier than the controls. At 90 days the experimental fish were 163.07%, 200.33% and 228.79% heavier than the controls for testosterone, 11‐ketotestosterone and adrenosterone respectively. Similar increases in total length were also recorded. These results illustrate the potential use for natural sex steroids in aquaculture.
EFFECT OF FREEZING METHODS ON THE QUALITY OF THE PRAWN, Macrobrachium rosenbergii1
Authors: Nip W. K. , Moy J. H.
Published: August 2010

Fresh water prawn (Macrobrachium rosenbergii) has a shelf‐life of only 3–4 days. Its deterioration usually starts with softening of the abdominal tissues. Freezing studies were conducted to determine qualities of the prawn after one month of frozen storage. Freezing methods include liquid nitrogen dipping, still air at ‐13 to ‐19°C, and freezing in brine at ‐6 to ‐18°C. Total bacterial count, pH, trimethylaminenitrogen and salt content were measured on previously frozen, thawed samples. Texture profile and sensory evaluation were measured on thawed, then cooked samples.

Loss of muscle elasticity and lowering of viable bacterial counts were found in all the frozen‐then‐thawed samples. No significant losses of sensory qualities on the cooked samples were observed, with samples frozen with liquid nitrogen scored closer to fresh samples. Overall qualities of previously frozen samples were judged acceptable.
THE RESPONSE OF ALL‐MALE TILAPIA HYBRIDS TO FOUR LEVELS OF PROTEIN IN ISOCALORIC DIETS
Authors: Newman Mark W. , Huezo Hugo E. , Hughes David G.
Published: August 2010

Twenty 20–m3 concrete tanks with non‐flowing water were stocked with all‐male tilapia hybrids (male Tilapia hornorum X female T. nilotica) at a rate of 1.5 fish/m3. Four diets of equal gross caloric content (isocaloric) containing 20, 25, 30, and 35% protein of equal quality were tested to evaluate the growth response of tilapia to protein quantity. No significant difference in growth was produced by any diet. It was more economical to use 20% protein in the diets than higher levels.
FOAM FRACTIONATION APPLIED TO AQUACULTURAL SYSTEMS1
Authors: Wheaton F. W. , Lawson T. B. , Lomax K. M.
Published: August 2010

Foam fractionation is discussed as a means of removing contaminants from seafood processing plant effluents and fish culture systems. Fractionator operating modes are discussed as are the parameters affecting operation and performance. Use of a foam fractionator for contaminant removal from blue crab processing plant effluent and from fish culture systems is reported and results are briefly discussed.
OZONE DISINFECTION OF FISH HATCHERY WATERS: PILOT PLANT RESULTS, PROTOTYPE DESIGN AND CONTROL CONSIDERATIONS
Authors: Oakes Dan , Cooley Paul , Edwards Louis L. , Hirsch Robert W. , Miller Victor G.
Published: August 2010

For over two years, ozone pilot plant studies have been conducted examining the efficacy of disinfecting makeup water entering the Dworshak National Fish Hatchery at Orofino, Idaho. The major pilot plant equipment consisted of a 1.12 kg/day Union Carbide Ozone Generator and contacting column.

Plate counts for total bacteria were taken at various points in the pilot plant. Similar plate counts were taken from existing ultraviolet disinfection equipment. Also monitored were ozone residual levels entering and within the recycle system, ammonia, nitrate, nitrite, total organic nitrogen, suspended solids, turbidity and biochemical oxygen demand. Analysis of the plate counts shows ozone consistently provides more effective disinfection of the makeup water than the existing ultraviolet system. Nitrite levels after ozonation show a significant decrease, while nitrate levels increased. Ozone disinfection of recycle water was also satisfactorily demonstrated. Additionally, batch studies indicate ozone effectively destroyed algae.

The pilot work established Dworshak ozone requirements to disinfect both makeup and recycle water. Experimental ozone demand, residual ozone removal rates, and ozone decay rates make it possible to design equipment and controls that will protect the fish from unsafe ozone concentrations. An ozone disinfection system preliminary design for a typical recycle fish hatchery is presented.
WINTER CULTURE OF Penaeus vannamei IN PONDS RECEIVING THERMAL EFFLUENT AT DIFFERENT RATES
Authors: Chamberlain G. W. , Hutchins D. L. , Lawrence A. L. , Parker J. C.
Published: August 2010

Penaeus vannamei were cultured from 3 November 1978 to 10 April 1979 in eight 0.1‐ha ponds at the Texas A&M mariculture facility located at Central Power and Light Company's Barney M. Davis Power Station in Corpus Christi, Texas. Four treatments were established using 3 flow rates of thermal effluent (high, medium, and low) and 2 feeding rates (3 and 4%). Survival, growth, and distribution of shrimp within ponds were monitored using cast‐net sampling. The low‐flow ponds suffered 94% mortality during the first major cold front when temperatures dropped to 5.2°C. Survival increased strongly with each increase in flow rate to a maximum of 33.7–82.3% in high‐flow ponds. Low‐temperature mortality of P. vannamei appeared to begin below 8°C regardless of acclimation and to occur at temperatures as high as 12°C depending on acclimation. Growth rates among treatments ranged from ‐0.03 to 0.06 g/day with the highest rate found in the high‐flow ponds with 4% feeding rate. A regression of growth rates on mean temperatures for all ponds fed at the 3% rate indicated growth rates of 0.00 g/day at 15.9°C, 0.02 g/day at 20°C, and 0.05 g/day at 25.0°C. The 4% feeding rate treatment yielded greater survival, growth, food conversion efficiency, digestive gland index, and spermatophore production than the 3% feeding rate treatment. Cast‐net catches of shrimp artificially declined below 21°C, apparently due to increased burrowing activity. The distribution of P. vannamei within ponds indicated a preference for deeper waters during the day and a more even distribution at night.
EFFECT OF OZONE TREATMENT ON THE SURVIVAL OF PRAWN LARVAE (Macrobrachium rosenbergii de Man) REARED IN A CLOSED‐RECIRCULATING WATER SYSTEM
Authors: Menasveta Piamsak
Published: August 2010

Ozone treatment in a closed‐recirculating water system significantly improved survival of freshwater prawn larvae. Post‐larval production in several rearing trials varied from 6–17.5 prawns per liter of water. This improvement over the mean of 4.1 larvae/liter achieved in the non‐ozonated controls might be due to the positive effects of ozone on the water quality. For instance, it can accelerate the conversion of nitrogenous wastes into the stable forms and it can serve as a prophylactic chemical with no retaining effect.
A MARICULTURE DEMONSTRATION PROJECT FOR AN ALTERNATIVE HARD CLAM FISHERY IN SOUTH CAROLINA: PRELIMINARY RESULTS1
Authors: Manzi John J. , Burrell Victor G. , Carson W. Z.
Published: August 2010

Intensive hard clam (Mercenaria mercenaria) culture for the production of large seed and/or market size quahogs is being investigated as an alternative or supplemental clam fishery for South Carolina. A combination of cage culture and aggregate cover (crushed gravel) is being used in subtidal, intertidal, and floating configurations. Young seed clams (ȳ size = 3.4 mm) are planted at four densities (500, 1,000, 2,500, 5,000 m‐2) in both production and experimental culture units at each of four locations along the South Carolina coast. Experimental units are divided into 0.1 m2 compartments to provide monthly replicate samples for each density. Coincidental water samples are taken monthly at each location for determinations of chlorophyll a, nitrate and nitrite nitrogen, orthophosphate, silicate, total organic carbon, particulate organic carbon, and dissolved organic carbon, as well as standard hydrographic parameters (temperature, salinity, turbidity). Results from preliminary bottom tray culture studies as well as ongoing cageaggregate culture are presented and discussed.
DESIGN AND OVERWINTERING OF A SOLAR HEATED RECIRCULATING MARINE POLYCULTURE SYSTEM
Authors: Ogle John
Published: August 2010

The construction of a passively solar heated marine recirculating culture system and its operation through the winter of 1978–1979 is presented. A recirculating marine polyculture system was designed and constructed to maintain a minimum water temperature of 20°C (70°F) utilizing solar heat. The system consisted of a 4000‐liter insulated raceway covered with 9.3 m2 (100 ft2) of solar panels. Filtration was provided by a 0.74 m2 (8 ft2) submerged filter composed of 0.22 m3 (8 ft3) of clam shells and 0.03 m3 (1 ft3) of foam rubber. A marine alga was used to denitrify the water before recycling. Twenty‐six airlifts recirculated the raceway water at a velocity of 0.6 m/sec. Flow through the filter was 6 liters/min with a retention time of 2 hours and an overall system turnover of 2.2 per day. Pompano (Trachinotus carolinus) and red snapper (Lutjanus campechanus) were used as indicator organisms (due to their sensitivity to low temperatures). Mullet (Mugil cephalus) were stocked to reduce phytoplankton growth. Suspended solids were reduced by biodeposition of oysters in a settling tank. Additional filtration consisted of a protein skimmer used intermittently.
COMMERCIAL AQUACULTURE SYSTEMS FOR CRAWFISH IN THE NORTHEASTERN UNITED STATES
Authors: Nolfi James R.
Published: August 2010

This paper examines several alternative strategies for the development of supply and demand (market) for freshwater crawfish produced through aquaculture in the northeastern United States. The potential for four species (Orconectes virilis, O. immunis, Procambarus clarkii and Pacifastacus leniusculus) will be examined in each of the following aquaculture production systems: a) wildstock fishery, b) planting in ponds, c) ponds with supplemental feeding, d) extended season ponds, e) hatchery and grow‐out, and f) fully closed systems.

Demand for crawfish is examined in three categories: scientific and instructional use, bait for angling, and human food. The food market demand, which will receive the greatest attention, is examined in terms of three potential directions: local specialty markets, mid distance (regional) metropolitan markets, and international markets. The paper summarizes the potential systems, given present and proposed future barriers and opportunities for the development of commercial culture systems.
PUMPING CHARACTERISTICS OF SMALL AIRLIFT PUMPS
Authors: Castro Walter E. , Zielinski Paul B.
Published: August 2010

Because airlift pumps are used extensively in mariculture systems, reliable performance data are required for efficient system operation. This study was initiated when it was found that reliable performance data were not available in the literature for pumps of short length (under 3 m) and small diameter (2–8 cm). Data for so‐called high lift pumps are available but initial work showed that the extrapolation of this data to small airlift pumps gives unreliable results.

The paper describes the experimental apparatus used to obtain flowrate data for the small airlift pump. These data are presented in tabular form for the benefit of the reader. Empirical equations using “best fit” correlations are also presented for convenience.

The paper also presents data on the staging of an airlift pump. That is an airlift pump with a single air inlet but outlets at different vertical locations (stages) along the pump. One possible use for a staged pump is in an intensive culture system where the lower stage would provide flow circulation, while the upper stage would pump culture water from the tank for treatment. Results for a two‐stage pump are given and show that, in general, staging reduces pumping efficiency.

The final topic deals with tuning the pump for maximum flowrate. It is well known that the optimum liquid flowrate occurs for a relatively small range of air flowrates. Driving the pump with air flowrates greater or less than this optimum flowrate will cause a significant decrease in performance. However, it is shown that the pulsatile nature of the outflow can be used to determine the optimum air flowrate. Experimental results confirm that the measured pulsing frequency correlates well with the maximum liquid flowrate.
THE EFFECT OF FEED DENSITY ON THE GROWTH OF JUVENILE Mercenaria campechiensis, THE SOUTHERN HARD CLAM1
Authors: Goldstein B. B. , Roels O. A.
Published: August 2010

A Tahitian strain of Isochrysis sp. was grown in outdoors continuous culture and fed to juvenile Mercenaria campechiensis at five different cell densities: 5times105, 1times105, 5times104, and 1times104 cells/ml; these correspond to inflow algal protein concentrations of 56.01, 11.34, 5.15, and 1.28 μg‐at particulate protein nitrogen (PPN) per liter, respectively. A control group received only 1 μ‐filtered seawater. An additional control consisted of an identical experimental setup receiving 5times104 cells/ml, without animals. Each treatment went to duplicate populations of 100 animals of 0.1 g each. Each population had a whole wet weight of 10.0 g. The total flow rate to each population was 120ml/ min.

The filtered seawater, algal culture, and effluent from each shellfish population was sampled daily. All samples were analyzed for nitrite, nitrate, ammonia, urea, dissolved free amino acids, soluble protein, total dissolved nitrogen, and particulate protein.

The control treatment of 1 μ‐filtered seawater gave no growth. The most concentrated treatment (56.01 μg‐at PPN/1) gave good growth. However, better growth was obtained at concentrations of 5.75 and 11.34 μg‐at PPN/1. At the flow rates and population weights used, 56.01 μg‐at PPN/1 is too concentrated, resulting in poorer growth. The lease dense treatment (1times104 cells/ml or 1.28 μg‐at PPN/1) resulted in the poorest growth (other than the control). Under the experimental conditions used, this cell density apparently represents a suboptimum ration size.

The effect of feed density on the growth of juvenile M. campechiensis is discussed in terms of traditional models of growth as a function of ingested ration.
ECTOPARASITIC FAUNA OF GLASS EEL AND ELVER STAGES OF AMERICAN EEL (Anguilla rostrata)1
Authors: Crane John S. , Eversole Arnold G.
Published: August 2010

Glass eels and elvers collected biweekly from freshwater portions of Cooper River, South Carolina, during spring migrations (15 February‐26 April 1978) were examined for external parasites. No parasites were found on glass eels. Four species of Protozoa and one species of Monogenea were found on elvers, 62% of which harbored at least one parasite species. Management implications and potential chemical treatment for wild glass eels and elvers used in culture are discussed.
CHEMORECEPTION IN DECAPOD CRUSTACEA AND CHEMICAL FEEDING STIMULANTS AS POTENTIAL FEED ADDITIVES
Authors: Heinen John M.
Published: August 2010

Types of chemical feeding effectors are listed, and locations and functions of decapod chemoreceptors are discussed. Low molecular weight substances found most stimulatory in behavioral, physiological, and electrophysiological studies on decapods are tabulated. Most of these chemicals have not been widely tested, and some are prohibitively expensive for use in feeds. The most generally stimulatory single substances are L‐glutamic acid, glycine, and taurine. Mixtures of substances can be more effective than single substances; e.g., the use of betaine plus amino acids shows some promise.
INFLUENCE OF DIETARY PROTEIN CONCENTRATION ON GROWTH, FEED CONVERSION AND GENERAL METABOLISM OF JUVENILE PRAWN (Macrobrachium rosenbergii)1
Authors: Millikin Mark R. , Fortner Alan R. , Fair Patricia H. , Sick Lowell V.
Published: August 2010

Juvenile Macrobrachium rosenbergii cultured in closed systems were offered one of four dietary protein concentrations, each containing a 1.65:1 ratio of menhaden fish meal to soy proteinate. After 6 and 10 weeks, the 40 and 49% protein treatments promoted significantly higher weight gain than those individuals offered 32 and 23% protein. Additionally, during the same time intervals, the 32% protein treatment resulted in better growth of prawn than the 23% protein treatment. After 14 weeks, prawn fed the 40% protein concentration produced a significantly higher cumulative weight gain than prawn offered 49, 32 and 23% protein. Feed conversion ratios were significantly lower (i.e., better) in the 40% protein treatment compared to the 23% protein treatment after 10 and 14 weeks (P ≤ 0.05). Survival rates were similar for all dietary treatments within any one time interval (6, 10 and 14 weeks). Protein efficiency ratio was lower in prawn fed 49% protein vs 40% proten after 10 weeks. The 40% protein treatment was more cost‐effective than 49% protein treatment throughout the study when considering growth, feed conversion ratios and protein efficiency ratios.

Although these results indicate a higher total dietary protein requirement for this species than that reported for most other prawns (27–35% protein), exact requirements will undoubtedly vary with alterations of the amino acid profile, variation in dietary supplementation of macro‐and micronutrients other than protein, and changes in selected environmental factors.
INFLUENCE OF THE FEEDING LEVEL ON GROWTH, FEED CONVERSION, PROTEIN EFFICIENCY AND CHEMICAL COMPOSITION OF JUVENILE EUROPEAN SEA‐BASS (Dicentrarchus labrax)
Authors: Métailler R. , Dehapiot T. , Huelvan C. , Vendeville J. E.
Published: August 2010

Three experiments were carried out in which young European sea‐bass (average initial weight from 9 to 29 g) were submitted to different restricted food intakes based upon standard lots fed ad libitum.

Growth always improved with increasing food intake, but tended to reach a plateau. Body and nutritional parameters improved when food intake decreased to 70–80% of the ad libitum level. Chemical body composition was rather constant. Only lipids were clearly affected by food intake, increasing with it.

Food chemical composition greatly influenced body composition. When diets contained a high level of protein and a low level of carbohydrate, fat deposition in various parts of the body decreased significantly.
THE MATURATION AND SPAWNING OF Penaeus stylirostris UNDER CONTROLLED LABORATORY CONDITIONS
Authors: Brown A. , McVey J. P. , Scott B. M. , Williams T. D. , Middleditch B. S. , Lawrence A. L.
Published: August 2010

Approximately 35 female Penaeus stylirostris from Costa Rica and Mexico held at the National Marine Fisheries Service, Galveston Laboratory, mated and spawned at least 247 times within a 190‐day period producing over 98 times 106 eggs. Average fecundity was 397,000 eggs and each female spawned between 9 and 10 times. The hatching rate varied from 0–85% with an average around 50%.

Female shrimp were ablated and placed in 3 m diameter tanks at a sex ratio of 1:1. The salinity ranged from 20–30 ppt and water temperature was maintained at 29–30°C. The diet consisted of polychaete worms, squid and sometimes a pelleted food in the ratio of 1:2:1. The photo‐period was 14 h/day using standard fluorescent lighting. No natural sunlight was available to the shrimp.

Mating behavior was observed to start around 1400–1500 h and continued until 2200–2230 h and later. Female shrimp observed with a spermatophore were captured and placed in spawning tanks, and the water was treated with EDTA and Maracyn I and Maracyn II. Egg production and hatching rate were calculated for each spawning tank. Nauplii were transferred to the hatchery facility and viability determined for selected spawns. Survival to postlarvae varied considerably and no conclusions can be made at this time regarding the reasons for variability. Over 746,000 postlarvae were produced.
APPROACHES TO THE STUDY OF DOMESTICATION IN THE FRESHWATER PRAWN, Macrobrachium rosenbergii, WITH SPECIAL EMPHASIS ON THE ANUENUE AND MALAYSIAN STOCKS
Authors: Malecha S. , Sarver D. , Onizuka D.
Published: August 2010

We used the wide native distribution of the prawn (Macrobrachium rosenbergii) to search for intraspecific variation which may be useful in its domestication and assessing the degree to which it has progressed so far in the cultured Anuenue stock. Although the species gene pool appears to be diverse based on genetic distance calculations we could find no useful allometric variation in genetic stocks and their hybrids derived from imported founders representing geographic areas in the prawn's natural range. A set of behavioral tests showed a superior performance in growth of cultured Anuenue over other wild stocks suggesting that the former has undergone incipient domestication. A direct comparison in a battery of other tests between the Anuenue stock and its wild relative, the Malaysian stock, failed to confirm this. In fact, in 2 out of the 10 tests the Malaysian stock demonstrated superior performance. It appears that the Anuenue stock has diverged very little under culture from its wild relatives. This may be due to the current management practices in choosing brood stock.