bluuebunny/crossref_metadata_2025_split huggingface dataset:
Substitution of Soybean Protein for Fish Protein in Formulated Diets for Red Swamp Crawfish Procambarus clarkii1
Authors: Reigh Robert C. , Braden Stephanie L. , Laprarie Ralph J. 
Published: April 2007

AbstractA 10 week laboratory growth trial was conducted with red swamp crawfish Procambarus clarkii to determine the amount of soybean protein that could be substituted for fish protein in formulated crawfish diets without reducing growth. Crawfish received 32% crude protein, isocaloric diets in which protein was supplied by soybean (soy) meal, menhaden fish meal or an isonitrogenous mixture of soybean and fish meal calculated to provide graded levels of each protein source. Dietary protein was provided as: 1) 100% soy protein; 2) 75% soy protein: 25% fish protein; 3) 50% soy protein: 50% fish protein; 4) 25% soy protein: 75% fish protein; and 5) 100% fish protein. Crawfish fed soy protein: fish protein (SP:FP) mixtures or fish protein alone exhibited better (P < 0.05) weight gain than crawfish fed a diet containing soy protein as the only protein source. Diets containing 25% soy protein: 75% fish protein (1:3 ratio) and 50% soy protein: 50% fish protein (1:1 ratio) produced greater (P < 0.05) weight gains than a diet in which fish protein was the sole protein source. Survival, feed efficiency ratio, maturation rate, net protein and energy retention, and body composition of crawfish did not differ (P > 0.05) among diets with SP:FP ratios of 1:3, 1:1 and 3:1. However, maximum (P < 0.05) weight gain occurred in crawfish fed the 1:3 SP:FP ratio. Although crawfish fed SP:FP ratios of 1:1 and 3:1 had lower weight gains in the laboratory than crawfish fed a 1:3 SP:FP ratio, SP:FP ratios of 1:1 and 3:1 might be adequate for supplemental diets fed to pond‐reared crawfish that have access to natural sources of food.
Oxytetracycline Residue in Hybrid Striped Bass Muscle
Authors: Xu Dehai , Rogers Wilmer A. 
Published: April 2007

AbstractHybrid striped bass (Morose saxatilis male ×M. chrysops female) were injected with 25 and 50 mg oxytetracycline (OTC) per kg of fish. Rate of elimination of OTC from muscle tissue and inhibition of bacteria by muscle injected with OTC were studied. OTC residue in muscle of fish injected with 50 mg OTC/kg fish was much higher (P < 0.01) than that in fish injected with 25 mg/kg and took a longer time to clear from the muscle. In fish injected at 25 mg OTC/kg of fish, OTC was completely eliminated from muscle in 24 d; the rate of elimination constant (β) was 0.278/day and the half‐life (t1/2) 2.5 d. In fish injected at 50 mg OTC/kg of fish, the OTC was not depleted in fish muscle until 32 d after injection; the rate of elimination constant 13 was 0.265/day and the half‐life was 2.6 d. No statistical difference was found in muscle OTC residue between male and female fish. Size of fish (16.5 to 21.5 cm and 21.6 to 25.5 cm) made little difference in OTC residue in muscle. Muscle removed from fish injected with 25 mg/kg OTC 12 d after injection inhibited the growth of Vibrio anguillarum, V. ordalii and Aeromonas hydrophila in cultures.
An Analysis of Biological, Economic, and Engineering Factors Affecting the Cost of Fish Production in Recirculating Aquaculture Systems
Authors: Losordo Thomas M. , Westerman Philip W. 
Published: April 2007

AbstractAquaculture production in recirculating systems has been the focus of research and development efforts for decades. Although considerable resources have been expended on these systems in the private sector, there is a scarcity of data on the economic or engineering performance of commercial scale recirculating production systems. This paper presents the results of a computer simulation of tilapia production in a small recirculating production system. Much of the performance data has been developed at a demonstration facility at North Carolina State University. Given the assumptions of the base case simulation, the cost of producing a kilogram of tilapia in the recirculating system described is estimated to be $2.79 ($1.27/lb). The results of a model sensitivity analysis indicate that while improvements in the performance efficiency of system components did not greatly affect fish production costs, reductions in feed costs and improvements in the feed conversion ratio caused the greatest reduction of production cost of all of the operational variables investigated. The analysis further indicates that the greatest gains to be realized in improving profitability are those associated with increasing the productive capacity or decreasing the investment cost of a recirculating fish production system.
The Isolation and Propagation of Dero digitata Infected with Aurantiactinomyxon Sp.
Authors: Pote L. M. , Bellerud B. , Lin T. L. , Chenney E. F. 
Published: April 2007

AbstractTechniques were devised to facilitate the collection, isolation, and propogation of the aquatic oligochete Dero digitata infected with actinosporeans for the purpose of studying the causative agent of proliferative gill disease (PCD). Pond mud containing the infected D. digitata was collected using a modified Ekman dredge. The mud was covered with pond water, transported to the laboratory, and aerated at 25 C until further processing. Worms were separated from the mud using an elutriator and screen. Worms were rinsed from the screen, the wash was examined using a dissecting microscope, and all D. digitata were removed. These worms were individually placed into 96 well plates. Wells were checked with a dissecting microscope at 24, 48, and 72 h for the presence of actinosporeans. Those positive worms were placed into petri dishes with sterile spring water and 3–4 grains of sterile wheat and held at 25 C. These techniques allowed large numbers of infected D. digitata to be collected and retained for a year for research purposes.
Bacterial Degradation of Microencapsulated Foods Used in Larval Culture
Authors: Muir P. R. , Sution D. C. 
Published: April 2007

AbstractMicroencapsulated foods are widely used in the culture of larval fish, bivalves and crustaceans. The resistance to bacterial decay of two of these diets was investigated under microbial conditions similar to those found in hatchery cultures of larval penaeid prawndshrimps. A 2–3‐fold increase in total ammonia concentration and a 7–14‐fold increase in total bacterial numbers were detected within 48h when microcapsules were added to larval culture water at a density recommended by the manufacturer for one day of supplementary feeding. Increased dissolved total ammonia and bacterial populations were detected within 1.5h of addition of food to penaeid larval culture water. Scenning electron microscopy indicated that microcapsules were colonized by numerous bacterial cells within 1h. Physical disintegration of microcapsules occurred after 6 to 12h. Only in sterilized penaeid larval culture water did microcapsules remain intact for a significant period. These findings are discussed in relation to development of improved methods of larval culture.
The Effects of Enriching Live Foods With Highly Unsaturated Fatty Acids on the Growth and Fatty Acid Composition of Larval Red Drum Sciaenops ocellatus
Authors: Craig Steven R. , Arnold Connie R. , Holt G. Joan 
Published: April 2007

AbstractThree experiments were carried out to test the effects of enrichment of live food (rotifers) with varying levels of n‐3 highly unsaturated fatty acids (HUFA) on the growth rate and fatty acid composition of red drum larvae. Additionally, the fatty acid compositions of red drum eggs and day‐1 larvae were compared. The enrichment techniques were successful in that the levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were elevated in the rotifers fed the enrichment diet. Red drum larvae fed the control rotifers produced the highest growth rate of the three experiments. Larvae fed rotifers with no HUFA supplement (NHUFA) had a significantly lower growth rate than the controls for that experiment. The fatty acid compositions of the eggs and day‐1 larvae did not vary significantly and contained high levels of 16:0, 16:1 n‐7 and DHA (22:6 n‐3). Based on these data, the lack of DHA in the diet significantly reduced the growth rates of larval red drum. The 10‐day‐old red drum larvae had similar fatty acid profiles at the end of the experiments regardless of the diet they were fed, indicating that dietary inputs have little effect on the fatty acid composition of larvae during the first ten days of growth. Red drum larvae appear to have the ability, though limited, to bioconvert EPA to DHA since there was a significant increase in the levels of DHA from day 1 to day 10 in the NHUFA larvae. However, the efficiency of this bioconversion is not sufficient for optimal growth and supplemental DHA at least to the level found in the control rotifers (0.3–0.4mg/100mg tissue) is necessary to maximize growth. The exact role of EPA could not be determined from this study due to the inability to produce an EPA‐free rotifer.
Hormones and Egg/Larval Quality in Fish
Authors: Lam T. J. 
Published: April 2007

AbstractRecent evidence suggests that hormones are passed on to eggs by broodfish. This store of maternal hormones may fill the regulatory needs of fish larvae for growth, development, osmoregulation, stress response and other physiological functions prior to the functional development of their own endocrine glands. Thus the hormonal levels in eggs/larvae may be an important determinant of egg/larval quality.Thyroid hormones have been best studied in this regard. Both thyroxine (T4) and triiodothyronine (T3) are present in fish eggs and in most cases, the levels decrease as development proceeds until the onset of endogenous thyroid hormone production, which usually occurs before or at around yolk‐sac resorption. Enhancement of T4/T3 levels in newly‐hatched larvae through immersion or maternal injection has been shown to promote larval growth, development and/or survival in several fish species, although overdose causes thyrotoxicosis.Other hormones such as corticosteroids, sex steroids, growth hormone and prolactin are also being studied, but to a much lesser extent.The paper reviews the evidence and discusses the practical implications of the various findings for larval rearing in aquaculture.
Effects of Broodstock Size and Source on Ovarian Maturation and Spawning of Penaeus monodon Fabricius from the Gulf of Thailand
Authors: Menasveta Piamsak , Sangpradub Sakon , Piyatiratitivorakul Somkiat , Fast Arlo W. 
Published: April 2007

AbstractThe effects of broodstock source (pond‐reared and wildcaught from shallow waters) and prawn size (large—weight >120 g, and small‐weight < 110 g) on ovarian maturation and reproductive success of Penueus monodon were evaluated. Large females underwent stage IV ovarian maturation and spawned with greater success than did small prawns. Both pond‐reared and wildcaught females of the same size exhibited comparable maturation and spawning success. Large females rematured and spawned more frequently than small ones. Total eggs produced by large prawns was significantly greater than for small prawns; nevertheless, prawn source and size had no significant influence on amount of eggs spawned per spawning event. Egg quality varied greatly in terms of percent fertilization, hatch rate, and metamorphosis to first protozwa stage.
Variability of the Microbial Environment of Rotifer Brahionis plicatilis and Avtemia Production Systems
Authors: Verdonck L. , Swings J. , Kersters K. , Dehasque M. , Sorgeloos P. , Leger P. 
Published: April 2007

AbstractSamplings were organized in three marine fish hatcheries. Samples were taken at different steps during the production of algae, rotifers and Artemia. There were 233 dominant colony types isolated for further characterization. The isolates were compared to each other and to reference strains of Phorobacrerium, Vibrio and Alreromonas, using cellular fatty acid fingerprints. Fatty acid profiles of the isolates were grouped using principal component analysis. The isolates fell into at least ten major groups, of which two correspond to the genera Vibrio and to Alteromonas, respectively. Some groups seem to be restricted to a particular type of live food or isolation site. Although 43% of the isolates belong to Vibrio, only a minority of them could be readily assigned to known species.
Lordotic Deformation and Abnormal Development of Swim Bladders in Some Hatchery‐Bred Marine Physoclistous Fish in Japan
Authors: Kitajima Chikara , Watanabe Takeshi , Tsukashima Yasuo , Fujita Shiro 
Published: April 2007

AbstractAt many hatcheries in Japan, a high incidence of lordosis is being reported among marine physoclistous juveniles of red sea bream, Japanese sea bass, and amberjack. Extensive studies being conducted since 1975 to tackle this problem have led to the following conclusions, and effective countermeasures are being proposed.During early larval development in the temporary physostomous stage, fish must be able to gulp air at the water surface for normal development of the swim bladder. The juveniles that fail to gulp air swim upward in an oblique position because of insufficient buoyancy, causing the backbone to curve in a V‐shape.The managerial solutions proposed are: 1) reduce the strong water current caused by vigorous aeration; 2) provide nutrient‐enriched rotifers to produce healthy swimming larvae; and 3) prevent any oily film formation on the water surface.
Mechanism of Pseudoalbinism in Flatfish: An Association Between Pigment Cell and Skin Differentiation
Authors: Seikai Tadahisa , Matsumoto Jiro 
Published: April 2007

AbstractTwo groups of flounder P. olivaceus larvae were reared under different conditions to provide either normally pigmented or pseudoalbinic metamorphosed juveniles. The process of the differentiation of skin and pigment cells during postembryonic development was analyzed by means of histological, histochemical and immunofluorescent assay methods. In parallel with these assays, the differentiation of pigment cells was examined with the use of organ and cell culture in vitro. The results obtained strongly suggested that pseudoalbinism was evoked as a result of disruption of the mechanisms that controlled the establishment of asymmetric skin structures during metamorphosis.
A Review of Di‐n‐Butylphthalate in the Aquatic Environment: Concerns Regarding Its Use in Salmonid Aquaculture
Authors: Burridge L. E. , Haya K. 
Published: April 2007

AbstractThe presence and effects of di‐n‐butylphthalate (DBP) in aquatic environments are reviewed. Particular attention is paid to the use of DBP as a solvent in the pesticide formulation, Aquagard®, used to treat salmonids against external parasites at aquaculture sites in Europe. DBP is sparingly soluble in water, is readily metabolized by fish, and has a high lethal threshold for aquatic organisms. It is, however, lipophilic, persistent in aquatic sediments, and is listed as a priority pollutant by the governments of Canada and United States. The dissemination of this compound directly to water raises several concerns which should be addressed by further research and increased monitoring.
Evaluation of Soybean Proteins as Replacements for Menhaden Fish Meal in Practical Diets for the Red Drum Sciaenops ocellatus
Authors: Davis D. Allen , Jirsa D. , Arnold C. R. 
Published: April 2007

AbstractA series of growth trials was conducted to evaluate the use of soy protein as a replacement for fish protein in isonitrogenous practical diets for juvenile red drum Sciacnops ocellatus. Feeds were offered at or in excess of satiation to juvenile red drum maintained at 26–28 C and a salinity of 25–35 ppt. In the first growth trial, red drum were offered one of four diets containing graded levels of menhaden fish meal, replacing solvent‐extracted soybean meal and soy‐protein isolates. Differences in weight gain, survival and feed efficiency ratios of the fish corresponded to increases in fish meal content of the diets. Due to poor performance of the fish maintained on the low (15%) fish meal diet, a methionine supplement was introduced into this diet at the midpoint of the growth trial. A positive increase in growth indicated a dietary deficiency of methionine and/or total sulfur amino acids in the unsupplemented diet. A positive response to dietary fish meal also occurred in the second growth trial despite the supplementation of L‐methionine in the test diets. In low fish meal diets the utilization of solvent extracted soybean meal or a soy‐protein isolate resulted in similar growth responses. Hence, the presence of an antinutrient did not likely cause reduced growth rates. In the third feeding trial, weight gain also increased with increasing fish meal content of the diet despite the equalization of digestible protein and selected amino acids. There were no significant differences in whole‐body compositions which indicated similar biological value of the diets (protein digestibility, amino acid balance and energy availability). The singular deletion of fish‐solubles, glycine, lysine and methionine from the diet containing the lowest level of fish meal (10 g/100 g diet) did not result in significant changes in weight gain. This indicated that these components did not add to the nutritive value and/or palatability of this formulation. The final experiment was designed to evaluate the response of red drum to a control diet (high fish meal) as compared to a low fish meal diet with and without potential attractants/palatability enhancers. Weight gain and feed efficiency ratios of fish offered the low fish meal diet supplemented with seafood flavor or fish flavor #2 were not significantly different from the control (high fish meal diet). Based on the results of this study, with suitable formulation restrictions, soy protein is acceptable for inclusion in practical diet formulations for red drum. However, soy protein itself does not appear replete in sulfur‐containing amino acids and does not have acceptable palatability properties. Consequently, feeds containing reduced levels of marine proteins could require suitable attractants and/or amino acid supplements.
Semi‐Intensive Commercial Grow‐Out of Penaeus vannamei Fed Diets Containing Differing Levels of Crude Protein During Wet and Dry Seasons in Honduras
Authors: Teichert‐Coddington David R. , Rodriguez Rigoberto 
Published: April 2007

AbstractShrimp were grown under ideal management conditions during two distinct seasons of the year at stocking densities used most often in Honduras with the objective of evaluating the usefulness of high protein diets. A randomized design in 2 × 2 factorial arrangement was used to test a diet composed of either 20 or 40% crude protein in earthen ponds that were stocked with juvenile Penaeus vannamei at 5 to 11/m2. The study was repeated during wet and dry seasons. Dietary protein level had no significant effect (P > O.05) on survival, yield, or average weight of shrimp at either density during either season. Higher stocking rates yielded significantly greater shrimp production during both seasons. Mean shrimp weight in high density ponds was significantly lower than mean shrimp weight in low density ponds during the wet season, but there was no significant weight difference because of stocking density during the dry season. Mean survival was significantly lower at the higher stocking rate during the dry season. Net income was negative during the dry season, particularly at the high stocking density. Mean production was 240% greater in the wet season than in the dry season. Diets offered P. vannamei stocked at 5 to 11/m2 should contain no more than 20% protein, regardless of season. Higher dietary protein levels increase costs and waste nitrogen without resulting in greater shrimp yields. The high stocking density might increase profitability in the wet season, but long term sustainable production may be more feasible at lower stocking rates because of reduced nutrient wastes.
Design Procedure for Hooded Surface Oxygen Absorption Systems
Authors: Watten Barnaby J. 
Published: April 2007

AbstractA design procedure addressing effluent total dissolved gas pressure limits along with standard performance indicators such as oxygen absorption efficiency (kg absorbed/kg applied), and transfer efficiency (kg/kW.h), is presented for surface agitation equipment operating in an oxygen‐enriched atmosphere. Application of this contactor type in closed culture systems is attractive given its insensitivity to biological fouling and ability to operate without the need for a significant hydraulic gradient. Performance algorithms were developed through application of chemical reactor theory, Henry's Law and the Ideal Gas Law. In the analysis, gas and liquid phases were treated as being homogeneous. The design steps presented are unique in that required mass transfer coefficients (KLa), operating pressures (CP), and oxygen feed rates (G/L) are calculated for target changes in both dissolved oxygen and nitrogen without the use of iterative numerical procedures. A second calculation sequence establishes the sensitivity of system performance to changes in G/L when CP and KLa are known.
Predicting Crawfish Molting with Machine Vision
Authors: Timmermans Toine , Sistler Frederick E. , Lawson Thomas B. 
Published: April 2007

AbstractThe objective of this project was to develop a vision system that could predict when crawfish will molt. Different sections of the crawfish shell were examined to determine how the color changed as the time of molting approached. A strip on the tail section of the crawfish showed the greatest, most consistent color change. The average red/green × red/blue ratio decreased for every crawfish as the molting time approached. Using this ratio as a predictor, it was possible to predict the molting of a crawfish within 3 d with an accuracy greater than 80%. The limitation on accuracy was primarily the result of the large variations in natural shell color among the crawfish.
Egg Water Induced Reaction and Biostain Assay of Sperm from Marine Shrimp Penaeus vannamei: Dietary Effects on Sperm Quality
Authors: Wang Qingyin , Misamore Michael , Jiang Charlie Q. , Browdy Craig L. 
Published: April 2007

AbstractReproductive performance was evaluated for sexually mature male Penueus vannamei fed one of four diets: 1) commercial 40% protein shrimp growout diet; 2) 100% squid; 3) 50% squid, 25% bloodworms and 25%Artemia; and 4) starvation. Spermatophores were ejaculated manually from tagged males at stocking and every 12 d thereafter. For each half of the compound spermatophore, weight and sperm count were determined. Four methods were used to assay the sperm quality: 1) gross morphology (GM); 2) trypan blue stain (TB); 3) acridine orange stain (AO); and 4) egg water induced reaction (EW). The reaction induced when P. vannamei sperm are exposed to conspecific egg water is grossly similar to that observed in vivo at the surface of the freshly spawned eggs from naturally mated females. Little correlation was found between spermatophore weight and sperm count. The best correlation was found between GM and AO (r2= 0.859, P < 0.01). Many morphologically abnormal sperm did not stain with TB. For most of the spermatophores evaluated; over 80% of the sperm were morphologically normal, were unstained with TB, and were immediately fluorescing light green when stained with AO. When exposed to egg water, sperm from these apparently good quality spermatophores yielded mixed results. The analysis of dietary effects on spermatophore quality were equivocal. Although a significant decline in body weight, spermatophore weight, and sperm count were observed in the starvation treatment as compared to maturation and squid diets, no significant differences were observed in MY of the sperm quality assays.