bluuebunny/crossref_metadata_2025_split huggingface dataset:
STUDIES ON COMPOUNDED DIETS FOR Penaeus kerathurus SHRIMP
Authors: Fernández Ramón , Puchal Francisco 
Published: August 2010

ABSTRACTThe apparent large differences in nutritive requirements reported for different shrimp species precludes extrapolation of available data from one species to another. This fact and the general scarcity of knowledge about crustacean dietary requirements presents a formidable problem to the nutritionist when beginning with a new shrimp candidate.The species used in these experiments was the Penaeus kerathurus, a shrimp native to the eastern Atlantic and Mediterranean coastline. A total of 1,000 postlarvae were used in six experimental trials, concerned with the acceptability of formulated rations and the effectiveness of different protein sources, and considering previous techniques carried out in this field. Other aspects examined were the influence of natural food (mussel mantle and gonad) as a complement to the artificial diet, and the presence in it of an unidentified growth factor(s).From the results obtained, the acceptability of the compounded diets stands out. However, these diets failed to support greater than 50–55% of the fresh mussel diet growth in all experiments. This observation and the strong reduction in nutritional value of the fresh food by processing are related by two possible explanations: first, the rapid leaching of water‐soluble nutrients, and second, the idea of a labile unknown metabolite essential for the growth of these animals.
TRACE CONTAMINANT ACCUMULATION BY ORGANISMS GROWN IN A WASTE RECYCLING AQUACULTURE SYSTEM1
Authors: Mann Roger , Ryther John H. 
Published: August 2010

ABSTRACTThree species of bivalve mollusc Crassostrea gigas (Thunberg), Ostrea edulis L., Tapes philippinarum (Adams and Reeve), one species of crustacean, Homarus americanus, and one species of macroscopic algae Gracilariopsis sjostedtii were grown in a pilot‐scale marine waste recycling aquaculture system for a period of 18 months. Organisms were exposed to 14 different regimes of food chain enrichment using either secondary treated sewage effluent, a mixture of inorganic nitrogen and phosphorus compounds free of contaminants, or a combination of both to simulate “growth” and “depuration” periods in an on‐site application. Throughout the study organisms were sacrificed at monthly intervals and assayed for 7 trace metals (Cd, Cr, Cu, Hg, Ni, Pb, Zn). Sewage effluent used for food chain enrichment was assayed for the same suite of metals three times per week. No significant differences were evident between organisms cultured in the contaminant‐free and effluent enriched regimes. Shellfish trace metal contents were consistently below FDA “alert” levels. H. americanus trace metal levels were within acceptable standards for human consumption. Trace metal levels in G. sjostedtii were comparable with those recorded for natural populations of macrophytes. Data suggest that trace metals constitute a minimal public health problem in organisms cultured for human consumption in waste recycling systems; however, problems related to organic residues and viruses have yet to be fully evaluated.
POTENTIAL FOR COMMUNAL REARING OF THE NEPHROPID LOBSTERS (Homarus spp.)1
Authors: Carlberg James M. , Van Olst Jon C. , Ford Richard F. 
Published: August 2010

ABSTRACTA series of experiments was conducted with American lobsters (Homarus americanus) and European lobsters (Homarus gammarus) to develop methods to reduce cannibalism among communally‐reared juveniles. The primary factors studied were substrate type, stocking density and photoperiod. Other conditions investigated were the effects of different water Temperatures, food type, segregating large individuals and claw immobilization. Preliminary studies also were conducted on the effects of shelter density, feeding level and tank area. These studies showed that by the use of vertical substrates, segregating techniques and immobilization of claws, carrying capacity can be increased considerably.
GENETIC DIVERGENCE AND BIOGEOGRAPHY OF NATURAL POPULATIONS OF Macrobrachium rosenbergii
Authors: Hedgecock D. , Stelmach D. J. , Nelson K. , Lindenfelser M. E. , Malecha S. R. 
Published: August 2010

ABSTRACTElectrophoretic studies of gene‐enzyme variation in natural populations of the freshwater prawn (Macrobrachium rosenbergii) are undertaken to quantify the amount of racial divergence among geographically separated natural populations. A total of 440 individuals from 11 localities spread from Sri Lanka to New Guinea, Palau and the Hawaiian cultured stocks are analyzed for genetic variation in as many as 31 electrophoretically detectable proteins. Within‐population variability is relatively low: the average proportion of heterozygous loci in any given individual is 2.8% and the average proportion of polymorphic geneenzymes per population is 14%.Population differences are summarized by proportions of loci having no genotypes in common between populations (“% diagnostic loci”). Prawn populations from Australia, New Guinea, the Philippines, and Palau are well differentiated from the rest, with genetically fixed enzyme differences at over 20% of the gene‐enzyme systems. That this major discontinuity in the gene pool of M. rosenbergii corresponds to the well recognized zoogeographic boundary known as Wallace' Line suggests that insular distribution has contributed to genetic divergence.One or 2 fixed or nearly fixed differences were also found among populations within the 2 major races east and west of Wallace' Line. These results support the hypothesis that this species has undergone substantial racial divergence over its range and that natural populations represent a tremendously diverse genetic resource for freshwater prawn aquaculture.
THE STATUS OF MACROBRACHIUM FARMING IN THAILAND
Authors: Singholka Somsuk , New Michael B. , Vorasayan Paiboon 
Published: August 2010

ABSTRACTThe farming of Macrobrachium rosenbergii is widespread in Thailand. Currently over 200 farms are being supplied with juveniles from the main government hatchery. Many small “backyard” hatcheries exist and the number of large commercial hatcheries and production farms is increasing. Over half the Thai provinces have Macrobrachium farms but the species is still being imported to satisfy local demand. Production of farmed freshwater prawns is estimated at 245 tons per year in 1979. Retail market values of US $10.00–12.50/kg, whole, shell‐on give the industry a scale of nearly US $2.8 million annually. Unsatisfied local demand, together with optimal rearing conditions and export potential, promises to stimulate further significant development in this industry in Thailand.
WATER CIRCULATION FOR POND AERATION AND ENERGY CONSERVATION
Authors: Busch Charles D. 
Published: August 2010

ABSTRACTOxygen transfer theory has shown that use of mechanical aerators may decrease instead of increase pond water oxygen levels. Photosynthetic production of oxygen can result in supersaturated concentrations while the maximum level attainable using mechanical aeration is saturation. Based on these observations a new paddlewheel has been designed and tested to provide stirring of pond waters instead of splashing, bubbling or spraying. The tests demonstrated that daytime circulation can serve to increase dissolved oxygen content in the deeper portions of the pond during the following night. The concept of aeration through pond circulation requires only a fraction of the power associated with most existing aerators.
SMALL‐SCALE MASS CULTURE OF Daphnia magna Straus
Authors: Rees John T. , Oldfather Joan M. 
Published: August 2010

ABSTRACTDaphnia magna Straus 1820 was reared on a defined medium in 4‐liter flasks under controlled conditions of light, temperature and species of algal food. Adult D. magna were found to be tolerant of high levels of ammonia, up to 108 μM, at high pH (>10), although parthenogenic reproduction may be inhibited at these high levels. Scenedesmus quadricauda and Ankistrodesmus sp. were found to be satisfactory food sources. Densities of greater than one animal per ml in culture were attained utilizing Ankistrodesmus sp. as a food source at a pH of 7.7. Maintenance of pH at around 7–8 appears to be important to successful D. magna culture.
THE MASS CULTURE OF THE ROTIFER, Brachionus plicatilis, FOR USE AS FOODSTUFF IN AQUACULTURE1
Authors: Fontaine Clark T. , Revera Dickie B. 
Published: August 2010

ABSTRACTDiscussed is the mass culture of rotifers at the National Marine Fisheries Service, Southeast Fisheries Center, Galveston Laboratory, Galveston, Texas, in the Galveston penaeid shrimp hatchery system and for use in marine fish larval culture. Techniques are described for: 1) harvesting rotifer tanks by “skimming” the surface of the water; 2) concentrating the harvested rotifers by shocking with deionized water; and 3) storing large quantities of rotifers to be used as foodstuff by conventional freezing methods. Also discussed is a technique being developed whereby the rotifer is used as a carrier medium for various nutrients.
RELEASE OF HATCHERY‐REARED BAY SCALLOPS (Argopecten irradians) ONTO A SHALLOW COASTAL BOTTOM IN WATERFORD, CONNECTICUT
Authors: Morgan D. E. , Goodsell J. , Matthiessen G. C. , Garey J. , Jacobson P. 
Published: August 2010

ABSTRACTSurvival and growth of hatchery‐reared bay scallops (Argopecten irradians) transferred to a shallow coastal area in outer Jordan Cove, Connecticut, were monitored by SCUBA during the summer and fall of 1979. In all, 47,000 bay scallops were released over 4 sequential seedings. Based on slopes derived from linear regression models the time to 50% loss of bay scallops from the release areas was less than one day for juveniles ≤22 mm and ≥6 days for scallops ≥24 mm. Significant (α = 0.05) reductions in the rate of loss occurred as scallop size increased at release. Scallops released with shell heights >45 mm had the lowest rates of loss. Both predation and dispersion effected these loss rates. Predation of scallops was attributed to the following benthic invertebrates: 6 species of crabs (Cancer borealis, Cancer irroratus, Carcinus maenus, Callinectes sapidus, Pagurus pollicarpus, Pagurus longicarpus), lobsters (Homarus americanus), 2 species of oyster drills (Urosalpinx cinerea and Eupleura caudata) and sea stars (Asterias forbesi). These predators contributed to most of the losses of bay scallops ≤22 mm and at least 20–50% of the losses in scallops ≥24 mm. Dispersion consisted of a northwest drift of scallops across the field study areas, which was probably enhanced by current patterns. Growth of bay scallops from October 3–24 was 0.26 mm/day and the rate of growth slowed as the water temperature dropped below 15°C.
SEASONAL VARIATION IN THE CONDITION OF RAFT‐CULTIVATED MUSSELS (Mytilus edulis L.)
Authors: Lutz Richard A. , Incze Lewis S. , Porter Barnaby , Stotz John K. 
Published: August 2010

ABSTRACTThe condition indices (wet meat volume and dry meat weight) of raft‐cultivated mussels from a north temperate estuary showed similar seasonal variations over a 3‐year period. Two periods of peak condition (one occurring in late spring and the other in the fall and early winter) were apparent during all 3 years of the study. A rapid decline in condition was observed at the end of May during each year, reflecting the period of spawning. A second decrease in condition was observed during August of each year, suggesting that a late summer spawning may be a general feature of the studied population. Although the precise timing and amplitude of the peaks in condition varied somewhat from year to year, high meat yields can be anticipated from early April through mid‐May and again from September through early winter in the environment studied. Results obtained in this study should provide useful guidelines for optimizing the productivity of commercial culture operations.
SOME FACTORS AFFECTING THE APPEARANCE OF EXTRACELLULAR HEMOLYSIN AND PROTEASE IN BATCH CULTURES OF THE OPPORTUNISTIC PATHOGEN Aeromonas hydrophila
Authors: Thompson Barbara T. , Riddle Lavon M. , Culley Dudley D. , Amborski Robert L. 
Published: August 2010

ABSTRACTAeromnas hydrophila, an opportunistic pathogen identified to be the causative agent of disease in many ectothermic animals, was grown in batch culture in a variety of complex and defined media to determine the effects of changes in medium composition on the production of extracellular hemolytic and proteolytic activities. A lag period of 24 hours was seen in cultures in defined media. This lag period was eliminated by adding yeast extract to the medium but was not eliminated by the addition of any of a group of vitamins or major energy and carbon sources. The effects of a group of trace minerals were studied, and it was found that zinc stimulated production of hemolysin, and that iron increased the growth yield and depressed both protease and hemolysin production. Although individual amino acids stimulated or retarded growth, changes in the amino acid composition of the medium did not greatly alter hemolysin production, in the absence of added zinc. In the presence of magnesium and zinc some amino acids stimulated hemolysin production.In view of the effects of the trace metals on toxin production in vitro, it is possible that nutritional immunity involving these metals could be a valuable exploitable defense mechanism in attempts to control Aeromonas‐caused disease.
STARVATION EFFECT ON METABOLISM OF Penaeus japonicus
Authors: Cuzon G. , Cahu C. , Aldrin J. F. , Messager J. L. , Stéphan G. , Mével M. 
Published: August 2010

ABSTRACTChanges in biochemical composition during starvation were studied in the shrimp Penaeus japonicus (Bate). Results indicate a progressive suppression of metabolism compared with normally fed shrimp. There is no significant decrease in the body weight over a period of 4 weeks starvation. Study of biochemical changes during starvation showed that P. japonicus consumed primarily carbohydrates, then lipids to meet its energy requirement; proteins were utilized significantly only during the final week of starvation. The evolution of the digestive gland index is measured together with hemolymph concentrations (glucose and total proteins) in order to interpret the physiological mechanisms of resistance to starvation.
HISTOLOGICAL OBSERVATIONS OF THE HEPATOPANCREAS IN JUVENILE LOBSTERS SUBJECTED TO DIETARY STRESS
Authors: Rosemark R. , Bowser P. R. , Baum N. 
Published: August 2010

ABSTRACTA study was designed to evaluate the hepatopancreas of the American lobster (Homarus americanus) as a potential indicator organ for early dietary stress. Seventy‐five 7th stage lobsters were divided into 3 groups. Group 1 was fed live brine shrimp (Artemia salina), group 2 was fed a sub‐optimal artificial diet (M4), and group 3 was starved. Three animals from each group were sacrificed at days 2, 4, 8, 12, 16, 22 and 29. The hepatopancreas from each animal was examined grossly and then prepared for histological evaluation. A general atrophy of especially the absorptive and secretory cells in the hepatopancreas of the starved animals was noticed as early as 4 days. In the hepatopancreas of the M4 fed juveniles, a progressive increase in the number of pycnotic nuclei and necrosis was evident by 8 days. Evidence of amyloid and ceroid were also observed. This ability to detect early cellular differences due to dietary deficiencies can be an important procedure for analyzing nutritional data.
MATURATION AND REPRODUCTION OF Penaeus setiferus IN CAPTIVITY
Authors: Lawrence A. L. , Akamine Y. , Middleditch B. S. , Chamberlain G. , Hutchins D. 
Published: August 2010

ABSTRACTRecently, the maturation and spawning of Penaeus setiferus in captivity was reported. However, none of the spawned eggs hatched. This paper reports the maturation and spawning of Penaeus setiferus in captivity with 0 to 75% of the spawned eggs hatching. The experiments were performed in 4.9 m diameter circular tanks at Marifarms, Inc. facility in Panama City, Florida. Each circular tank contained 70 to 80 animals with 1:1 female to male ratio. All females within 2 tanks were unilaterally ablated and all females in a third tank were unablated. The diet consisted of a 1:1:1 ratio of prepared dried feed or oysters, squid, and polychaete worms. The animals were fed 3% of their body weight each day. The feeding times were 0800, 1130 and 1500 hours. A natural light regimen was used with a salinity variation of 24 to 29 ppt and a temperature range of 27 to 31°C. Only unilaterally ablated females produced fertile eggs. Repeated spawns produced approximately 1,565,000 nauplii over a period of 30 days. Three groups totaling 865,000 nauplii were raised to 17‐day‐old postlarvae with an average survival of 65% at the Marifarms, Inc. hatchery. Thirty‐six thousand of these postlarvae were stocked in an integrated 3‐pond system at the Texas A&M facility in Corpus Christi, Texas. The animals grew to an average size of 8.1 g with 61.5% survival after 117 days in the pond. Thus, for the first time, laboratory maturation, repeated spawning, successful hatching, larval development and juvenile production was achieved for Penaeus setiferus.
THE IMPORTANCE OF SELECTING FOR SURVIVORSHIP IN GENETIC YIELD IMPROVEMENT PROGRAMS IN CRUSTACEAN AQUACULTURE
Authors: Doyle Roger W. , Hunte Wayne 
Published: August 2010

ABSTRACTMortality between “seeding” and harvest can cause serious loss of production in crustacean aquaculture. When a species is brought under cultivation for its complete life cycle, genetic changes inevitably result from natural selection in the controlled environment (domestication selection). Such changes can, in a properly designed program, lead to a reduction in the variability that is the source of much of the economic loss. Domestication selection resulted in a two‐fold increase in productivity in a model aquaculture program which involved cultivating the estuarine amphipod Gammarus lawrencianus in the laboratory. Approximately 75% of this gain was due to increased survivorship, the remainder to increased growth rate. Domestication selection will be beneficial in any crustacean with similar genetic relationships among the quantitative traits which determine yield. In aquaculture programs designed with genetic stock improvement in mind, it may be advantageous to reduce mortality by domestication selection before beginning conventional selection or inbreeding for individual traits such as growth rate. If this is not done, conventional programs may be counter‐productive because of their concentrating effect on “unfit” genes which are present in the population. Domestication can be accomplished by systematic feedback of progeny from the outgrowth ponds into the broodstock, and/or selection for lifespan, and/or selection for survivorship on a family basis.
OBSERVATIONS ON THE REPRODUCTIVE STATE OF MILKFISH POPULATIONS (Chanos chanos) FROM HYPERSALINE PONDS ON CHRISTMAS ISLAND (PACIFIC OCEAN)
Authors: Crear David 
Published: August 2010

ABSTRACTMilkfish (Chanos chanos) populations spawned in landlocked, hypersaline ponds on Christmas Island during 1976 and 1977. Specimens collected from one isolated population showed a mean gonadosomatic index (GSI) of 3.6. Virtually all males from this population were running ripe. Several mature females with GSI values ranging from approximately 15 to 25 were captured. One was running ripe. The high GSI maintained by this population and observations of running ripe fish and fingerlings in other ponds with salinities ranging from 60 to 130 ppt indicated that the milkfish spawn on a year‐round basis in these landlocked lagoons. Milkfish in hypersaline ponds matured sexually in spite of severely stunted growth. Mature fish from several hypersaline ponds (normal salinity 100–130 ppt) had mean weights of only one kilogram. Several adult milkfish were observed at salinities up to 158 ppt. Reproductive readiness in the fish appeared to be determined by the interaction of diet and salinity with the effect of diet prevailing. Inclusion of the brine shrimp (Artemia salina) in the diet of the milkfish was the strongest stimulant to the production of reproductive tissue. Stunted populations of milkfish on Christmas Island offer an attractive opportunity to study the reproductive physiology of the species due to the relative ease in handling the smaller fish.
Racial Profiling and Traffic Stops: An Examination of Research Approaches and Findings in the War on Drugs
Authors: Glover Karen S. , Penalosa Miguel , Schlarmann Aaron 
Published: August 2010

AbstractThis article is a review of some of the main research approaches to understanding racial profiling as it manifests in the traffic stop. It orients the emergence of racial profiling as a product of the war on drugs philosophy guiding law enforcement in the late 20th century and discusses how the contemporary nature of racial profiling has origins in a long history of racialized policing in the United States. Theoretical and methodological approaches to the issue, particularly from mainstream criminologists, focus on quantitative assessment of exposure to law enforcement agents and rational choice‐based arguments that it makes sense to target certain groups based on the hue of the criminal justice system. More critical approaches examined within complicate this notion by contextualizing racial profiling in contemporary times as a mere manifestation of historical efforts by the state to marginalize communities of color.
Prevalence of airflow limitation among employees in Norwegian smelters: a longitudinal study
Authors: Søyseth Vidar , Johnsen Helle Laier , Bugge Merete Drevvatne , Hetland Siri Merete , Kongerud Johny 
Published: August 2010

AimsTo investigate the association between airflow limitation and occupational exposure and to compare a fixed limit with an age adjusted limit for airflow limitation.Methods3924 employees in 24 Norwegian smelters and related workplaces were investigated annually over 5 years (n=16 570) using spirometry and a respiratory questionnaire on smoking habits and job category. Employees working full time on the production line were classified as line operators; subjects who never worked on the production line were regarded as non-exposed. A job exposure matrix (JEM) was available in most smelters. Airflow limitation was expressed as (i) forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC ratio) <0.7 and (ii) FEV1/FVC ratio less than the lower limit of normal (LLN). Longitudinal analyses on the prevalence of airflow limitation were performed using a generalised linear mixed model.ResultsThe prevalence of airflow limitation was stable during follow-up. The OR of airflow limitation during follow-up was 1.24 (95% CI 1.03 to 1.50) in line operators compared with unexposed subjects for FEV1/FVC ratio <0.7 and 1.44 (1.14 to 1.81) for FEV1/FVC ratio <LLN. A dose–response relationship was also found between prevalence of airflow limitation and dust exposure. The annual decline in FEV1was −77.5 (SD 99.9) ml/year in subjects with FEV1/FVC ratio <0.7 and −83.8 (114.2) ml/year in subjects with FEV1/FVC ratio <LLN.ConclusionPrevalence of airflow limitation was higher in exposed than non-exposed employees. Both the FEV1/FVC ratio <0.7 and FEV1/FVC ratio <LLN identify subjects with accelerated annual decline in FEV1.