bluuebunny/crossref_metadata_2025_split huggingface dataset:
Maximizing First‐Year Growth of Mixed‐Sex Blue Tilapia Oreochromis aureus in Polyculture with Catfish Ictalurus spp.
Authors: Morrison John R. , Deavours William L. , Jones J. C. , Tabb Mark A. 
Published: April 2007

AbstractMixed‐sex blue tilapia Oreochromis aureus fry were produced from indoor spawns in March and April. Fry were stocked in May at an average weight of 0.5 g at 0, 250, 750, or 2,500/ha into ponds which had been stocked previously with three catfish strains at a combined density of 10,000 fingerlings/ha. After a 167‐d culture period, from 15 May until 4 November, tilapia stocked at 250 or 750/ha grew to average harvest size approaching 0.45 kg. No significant difference in average size was observed between males and females except at the 2,500 tilapia/ha stocking density. Sixty percent of the tilapia polyculture ponds yielded no reproduction at harvest and maximum reproduction observed was 13.5 kg/ha. Lack of reproduction and the undeveloped state of sampled female ovaries indicated that most females had yet to attain sexual maturity. Catfish production and catfish feed conversion was not significantly different between tilapia polyculture and catfish monoculture ponds (P > 0.05). First seine hauls yielded over 88% of the total catfish harvest, but only an average of 3.9% of the marketable tilapia. Tilapia had no measurable impact on the incidence of catfish off‐flavor at any of three sample intervals. Overall average levels of TAN and nitrites did not differ significantly between treatments; however, mean chlorophyll a concentration was significantly higher (P > 0.05) in the 2,500 tilapia/ha treatment than at lower tilapia densities.
Nutritional Enhancement of n‐3 and n‐6 Fatty Acids in Rotifers and Artemia Nauplii by Feeding Spray‐dried Schizochytrium sp.
Authors: Barclay William , Zeller Sam 
Published: April 2007

AbstractA docosahexaenoic acid (DHA), 22:6(n‐3), rich strain of Schizochytrium sp. was used in a spray‐dried form to evaluate the enhancement of highly unsaturated fatty acids (HUFAs) in Artemia franciscana nauplii (Utah biotype) and the rotifer Brachionus plicatilis. This heterotrophic microalga was selected because of its high concentration of the longest chain HUFAs in the n‐3 and n‐6 series, DHA and docosapentaenoic acid (DPA), 22:5(n‐6), respectively. When 24‐h‐old Artemia nauplii were fed 400 mg/L of the algae for 24 h, the DHA content of the nauplii went from undetectable levels to 0.8% of dry weight and the omega‐3 HUFA eicosapentaenoic acid (EPA), 20:5n‐3, content went from 0.1% to 0.5% of dry weight in the nauplii. Similarly, 22:5(n‐6) increased in the nauplii from undetectable levels to 0.4% of dry weight, with a concomitant increase in arachidonic acid, (20:4n‐6), from trace to 0.3% of dry weight even though there was no arachidonic acid in the algal biomass. Similar enrichment patterns were observed in rotifers. The results suggest that spray‐dried cells of Schizochytrium sp. are effective in enriching Artemia naupli and rotifers in both n‐3 and n‐6 HUFAs. The results also suggest that Artemia nauplii and rotifers are capable of readily retroconverting 22:6(n‐3) to 20:5(n‐3) and 22:5(n‐6) to 20:4(n‐6) through the process of β‐oxidation, a well‐known process in mammals.
Continuous Monitoring of Dissolved Oxygen and Total Dissolved Gas Pressure Based on Head‐Space Partial Pressures
Authors: Watten Barnaby J. , Smith David R. , Ridge William J. 
Published: April 2007

AbstractWe describe an instrument prototype that measures total dissolved gas pressure (TGP) and dissolved oxygen (DO) without need for standard wetted probe membranes or gas permeable tubing. Measurements were based instead on gas‐phase partial pressures that develop within the head‐space of a pressure vessel, and on Henry's Law. Performance trials established that differences between standard instrumentation and test instrument OP readings average ‐1.6‐mm Hg (SD = 2.19, range ‐4.8 to ‐5.3) within the ΔP range of ‐72 to 123‐mm Hg. Additional trials demonstrated the ability of the instrument to closely follow positive and negative changes in TGP at rates approaching 30‐mm Hg/h. Here, the difference between test and standard instrumentation derived TGP averaged 3.4‐mm Hg (range 0–41). Differences in ΔP measured by test instrument and gasometer increased with water throughput; mean differences were ‐3.9, ‐4.3, and ‐6.0 for water throughput of 4.6, 6.7, and 7.8 L/min, respectively. However, time to reach 90% of the steady‐state instrument reading was highest for low water throughput; equilibrium times averaged 90.9, 44.4, and 44.7 min for water throughput of 4.6, 6.7, 7.8 L/min, respectively. Differences between titration and test‐instrumentation based DO measurements were acceptable, averaging ‐0.11 mg/L (SD = 0.41, range ‐0.85 to 0.85) over DO from 3.3 to 19.2 mg/L and for 11.1 and 24.2 C. Whereas test instrument DO readings were indistinguishable from Winkler titration at 24.2 C; at 11.1 C there was a tendency for test instrument readings to be lower than Winkler titration at DO < 14 mg/L and higher at DO > 14 mg/L. Trials conducted under biological fouling conditions demonstrated the test instrument's ability to operate with 30% of the maintenance required by standard instrumentation.
Growth and Body Composition of Juvenile Hybrid Bluegill Lepomis cyanellus × L. macrochirus Fed Practical Diets Containing Various Percentages of Protein
Authors: Webster Carl D. , Tiu Laura G. , Tidwell James H. 
Published: April 2007

AbstractGrowth, survival, and body composition were evaluated in two feeding trials using juvenile hybrid bluegill Lepomis cyanellus×L. macrochirus. In Experiment 1, hybrid bluegill (20 g) were stocked into 1.25‐m3 cages at a rate of 300 fish/cage and fed diets containing 35, 40, 44, or 48% protein for 12 wk. Fish meal comprised 32% of the dietary protein in all diets. Fish were fed all they could consume in 40 min. No significant differences (P > 0.05) in individual length, individual weight, specific growth rate (SGR), condition factor (K), and feed conversion ratio (FCR) were found among treatments and averaged 13.4 cm, 47.4 g, 1.02%/d, 1.96, and 4.06, respectively. Whole‐body composition of hybrid bluegill indicated that fish fed a diet containing 35% protein had a significantly lower (P < 0.05) percentage protein (56.3%) and a higher (P < 0.05) percentage lipid (29.3%) compared to fish fed diets containing 40, 44, and 48% protein. In Experiment 2, 15 hybrid bluegill (15 g) were stocked into 110‐L aquaria and fed one of four diets containing 28, 32, 36, or 38% protein for 10 wk. Fish were fed twice daily all they would consume in 20 min. Fish fed a diet containing 38% protein had higher (P < 0.05) percentage weight gain (265%) than fish fed diets containing 28% (203%) and 32% (219%) protein, but were not significantly different (P > 0.05) compared to fish fed a diet containing 36% protein (251%). Feed conversion ratio (FCR) of hybrid bluegill fed diets containing 36% and 38% protein (average 1.39) were significantly lower (P < 0.05) than fish fed a diet with 28% protein (1.73). Results from these studies indicate that hybrid bluegill can be fed a practical diet containing 35–36% protein (with fish meal comprising 32% of the protein). Further refinement of the diet formulation may allow producers to reduce diet and production costs.
Water Quality in Laboratory Soil‐Water Microcosms with Soils from Different Areas of Thailand
Authors: Boyd Claude E. , Munsiri Prasert 
Published: April 2007

AbstractForty‐five soil samples were collected from aquaculture areas in 23 provinces of Thailand to include six soil orders and wide variation in physical and chemical properties. Soil‐water microcosms were prepared containing 5 g of soil and 150 mL of distilled water. Microcosms were held on an oscillating table shaker (150 rpm) for 1 wk at 25 C in the dark. Water pH and concentrations of dissolved nutrients, total alkalinity, and total hardness were measured. Differences in properties within soil orders caused wide variation in composition of solutions and differences in concentrations of dissolved substances and pH were not related to soil order. Regression analyses revealed significant correlations between concentrations of soil nutrients extractable in dilute acid (0.05 N HCI plus O.025 N H2SO4) or in neutral, 1 N ammonium acetate and aqueous concentrations. Regression coefficients usually were higher for dilute‐acid extractable nutrients than for ammonium acetate extractable ones. Regression coeficients based on dilute‐acid extractable nutrients follow: soluble reactive phosphorus (r= 0.816); calcium (r= 0.685); magnesium (r= 0.470); potassium (r= 0.959); sodium (r= 0.977); manganese (r= 0.462); boron (r= 0.399). The correlation between soil and solution iron was not significant and aqueous concentrations of copper and zinc were below detection limit. Hardness was correlated with soil carbon (r= 0.710) and soil pH was a good predictor of alkalinity (r= 0.877). Soil pH and aqueous pH were highly correlated (r = 0.939). Findings suggest that soil characteristics can be used to predict pH and concentrations of several dissolved substances in soil‐water systems under aerobic conditions.
Uptake and Clearance of Edwardsiella ictaluri in the Peripheral Blood of Channel Catfish Ictalurus punctatus Fingerlings during Immersion Challenge
Authors: Wise David J. , Schwedler Thomas E. , Terhune Jeffery S. 
Published: April 2007

AbstractUptake and clearance of Edwardsiella ictaluri in the peripheral blood of channel catfish Ictalurus punctatus fingerlings were monitored for 216 h after exposure to E. ictaluri for 4 h and 8 h under static conditions. Most fish exposed to E. ictaluri developed bacteriemia 24 h post‐exposure, and by 72 h post‐exposure E. ictaluri was recovered from all the blood of all exposed fish. The number of E. ictaluri colony forming units (CFU) in the blood of moribund fish ranged between 1.7 × 103 to 1.6 × 105 CFU/50 μL whole blood. Clearance of bacteria from the blood was observed by 216 h post‐exposure and all fish surviving bacterial exposure developed agglutinating antibody against E. ictaluri. The pathogenesis of the infection was accompanied by the shedding of viable E. ictaluri into the water which may serve as a mechanism by which fish to fish transmission occurs.
Effect of Reducing Dietary Digestible Energy to Protein Ratio on Weight Gain and Body Fat of Juvenile Channel Catfish Ictalurus punctatus1
Authors: Li Meng H. , Robinson Edwin H. 
Published: April 2007

Abstract.A laboratory feeding trial was conducted to evaluate the effects of reducing digestible energy to protein (DE:P) ratios of practical diets on body fat and weight gain of channel catfish. Five diets were formulated to contain 32, 28, or 24% crude protein with typical DE:P ratios of 8.5, 9.9, or 11.4 kcal/g protein, respectively, and 28% or 24% protein with a reduced DE:P ratio of 8.5 kcal/g protein. Cellulose was used to adjust the DE:P ratio. Juvenile channel catfish Ictalurus punctatus (initial weight: 5.2 g/fish) were fed the experimental diets twice daily to apparent satiation for 12 wk. Fish fed the 28% protein diet with a reduced DE:P ratio of 8.5 kcal/g protein gained less weight and converted feed less efficiently than those fed the 28% protein diet with a typical DE:P ratio of 9.9 kcal/g protein. Fish fed the 24% protein diet with a reduced DE:P ratio of 8.5 kcal/g protein had a similar weight gain but converted feed less efficiently than those fed the 24% protein diet with a typical DE:P ratio of 11.4 kcal/g protein. Weight gain and feed conversion efficiency of fish fed the 32% protein diet with a typical DE:P ratio of 8.5 kcal/g protein were higher than for fish fed other diets except those fed the 28% protein diet with a DE:P ratio of 9.9 kcal/g protein. There were no differences in feed consumption and survival among dietary treatments. Fillet fat of fish fed the 24% and 28% protein diets with a reduced DE:P ratio was lower than that of the fish fed diets containing the same protein concentrations with typical DE:P ratios. At a DE:P ratio of 8.5 kcal/g protein, there were no differences in fillet fat concentration among fish fed diets containing different protein concentrations. There were no differences in fillet protein, moisture, and ash between fish fed the 24% or 28% protein diets containing reduced and typical DE:P ratios. Results from this study show that reducing DE:P ratios in practical diets lowers body fat but also depresses weight gain of channel catfish; thus it would not be economical to use this strategy to reduce body fat of the fish.
Partitioning of Fish and Diet Selection as Methods for the Reduction of Cannibalism inParalichthys dentatusLarviculture
Authors: Francis A. Ward , Bengtson David A. 
Published: April 2007

AbstractPartitioning of larvae and diet selection were examined as strategies to reduce cannibalism in summer flounderParalichthys dentatus. Methods of partitioning included physical grading by size, baffle interference, and a control. The baffle consisted of a barrier with cells 14‐mm square and walls 9‐mm high. The barrier was positioned horizontally at a depth where it would divide the tank into two equal volumes of water. Factors which may characterize cannibalism were quantified, including: total length, developmental stage, pigmentation, wet weight, and biomass. Engineered to reduce cannibalism, the baffle instead contributed to a decrease in survival for at least one experiment (P <0.05). Grading by size did not significantly increase survival over that of the untreated control (P >0.05). Mean developmental stage ofP. dentatusin the graded treatment was significantly less than fish in either the control or baffle treatments (P <0.05). A factorial design of partition strategy and weaning diet did not demonstrate any difference in survival or measured character (P >0.05). Finally, both inert feeds and liveArtemiasp. nauplii were examined for their contribution to the Occurrence of cannibalism. Predicted differences between live and artificial diets were not significant (P> 0.05). During experiments, cannibalism was principally observed in late larval and early juvenile stages and was not restricted to post‐metamorphic juveniles feeding on premeta‐morphic larvae. Methods normally employed to reduce cannibalism (partitioning of larvae and diet selection) do not appear to be effective forP. dentatus.
Bioassay Procedure for the Evaluation of Erythromycin Activity in Aquaculture Environments
Authors: Assaf Nasser A. , Pothuluri Jairaj V. , Wang Rong‐Fu , Cerniglia Carl E. , Moffitt Christine M. 
Published: April 2007

AbstractA new bioassay procedure was developed for the detection of erythromycin in aquaculture samples using a strain of a Stenotrophomonas as an indicator organism. Conventional disk‐plate and well‐plate radial diffusion assay procedures were developed, as well as a third procedure using the same indicator organism in Luria‐Bertani (LB) broth, supplemented with the indicator dye Brilliant Black (40 μg/mL) in a multi‐well microtiter plate. For both the disk‐plate and well‐plate radial diffusion assays, the response reflected in the size (width) of the growth inhibition zone, which was linear over the tested concentration range of 0.05 to 2.0 μg erythromycidml. The limit of quantitation of the bioassay was at 0.05 μg erythro‐mycidml. Among the three methods of assay tested with Stenotrophomonas sp., the semi‐quantitative dye reduction method is easy to read and is not diffusion dependent. This method allows for processing of more samples and more replication on a single titer plate. This new indicator organism is specific for erythromycin when tested in the presence of other antibacterial agents, i.e., oxytetracycline (Terramycin®) and/or Romet‐Ma. This new bioassay procedure is suitable for quantitation of low concentrations of erythromycin in aquaculture water and sediment samples.
Wildlife‐Caused Losses for Producers of Channel Catfish Ictalurus punctatus in 1996
Authors: Wywialowski Alice P 
Published: April 2007

AbstractThe National Agricultural Statistics Service surveyed by telephone and mail in January and February 1997 all known producers of channel catfish letalurus punctatus to acquire current information about wildlife‐caused losses in calendar year 1996. Many producers tried to prevent wildlife‐caused losses of their catfish by shooting (57%), vehicle patrol (55%), or frightening (36%), at an estimated cost of >$5 million. Yet, 69% of catfish producers cited some wildlife‐caused losses. Birds were most frequently cited as a cause of losses, and double‐crested cormorants Phalacrocorax auritus was the species cited most frequently (53%). The next most frequently cited birds were herons Ardea spp. (48%), egrets Egretta spp. (16%), and pelicans Pelecanus spp. (8%). Muskrats Ondatra zibethicus were cited by 10% of producers, primarily for damaging dikes and roads. The main problems caused by wildlife were feeding on catfish (67%), injuring catfish (40%) or disturbing feeding patterns of the catfish (23%). The total estimated cost of losses was $12 million. Overall, wildlife damage and damage prevention may have cost catfish producers > $17 million, about 4% of the total $425 million of catfish sales in 1996. Of the 44% of all catfish producers who were familiar with Wildlife Services (WS), 51% had ever contacted WS for assistance, 55% used methods suggested by WS to reduce their losses, and 40% received direct assistance from WS in 1996. Mississippi producers, who most frequently received direct assistance from WS, had proportionately lower wildlife‐caused losses.
Effect of Ozone Treatment on Cultures of Nannochloropsis oculata, Isochrysis galbana, and Chaetoceros gracilis
Authors: Kuresity Nasir , Davis D. Allen , Arnold C. R. 
Published: April 2007

AbstractThis research evaluated ozone treatment of three unicellular algal species commonly used in the culture of marine larvae. Isochrvsis galbana and Nannochloropsis oculata were found to be resistant to total residual oxidants (TRO); whereas, Chaetoceros gracilis was relatively sensitive to TRO. Isochrvsis galbana remained in log‐phase growth after treatment with 0.05 mg/L to 0.50 mg/L TRO, and N. oculata exhibited strong growth after being exposed to TRO levels up to 0.67 mg/L. Only TRO levels of 0.92 mg/L and 0.90 tng/L reduced cell counts of N. oculata and I. galbana, respectively. Furthermore, algal cultures having higher concentrations at the time of ozone treatment may respond more favorably to the treatment. Initially, C. gracilis was reduced in cell count at TRO levels above 0.06 mg/L, but log‐phase growth was resumed 2 d after exposure to TRO levels as high as 0.31 mg/L. It is concluded that I. galbana and N. oculata can be successfully treated with ozone in the mass production stages without hampering the timely production of concentrated cultures. Although C. gracilis was found to be relatively sensitive, ozone treatment of starter cultures can be performed routinely with this species. We have demonstrated that ozone treatment of algal cultures is a feasible technique, but studies need to be conducted on ozone treatment of other species of unicellular algae and on ozone treatment of varying concentrations of algae in order to enhance the applications of this technique. Also, in order to determine the extent of disinfection of algal cultures, bacterial and viral composition of the cultures should be evaluated in future studies.
Vaccination of Mixed and Full‐Sib Families of Channel Catfish Ictalurus punctatus Against Enteric Septicemia of Catfish With a Live Attenuated Edwardsiella ictaluri Isolate (RE‐33)
Authors: Wise David J. , Klesius Phillip H. , Shoemaker Craig A. , Wolters William R. 
Published: April 2007

AbstractThese studies were conducted to evaluate the efficacy of a live attenuated Edwardsiella ictaluri vaccine against enteric septicemia of catfish. In one study channel catfish fingerlings (72 d of age post hatch) were immersed for 30 min in water containing E. ictaluri RE‐33 at dosages of 1 × 106, 1 × 107 and 2 × 107 CFU/ML of water. No mortalities were observed following vaccination. Following exposure to virulent Edwardsiella ictaluri the cumulative mortality of fish vaccinated with dosages of at least 1 × 107 CFU/mL were significantly lower than that of non‐vacccinated fish in both laboratory and field challenges. Vaccination with 1 × 106 CFU RE‐33mL provided some protection during the laboratory challenge but failed to protect fish under field conditions. In a second study, vaccination of 6 full‐sib families of channel catfish at a vaccine dosage of 1 × 107 CFU/mL resulted in a relative percent survival among families ranging from 67.1 to 100%. Significant differences in mortality were found among families and between vaccinated and unvaccinated groups, but there was no family by vaccine interaction. Families with the highest mortality after vaccination were also shown to have the highest mortality without vaccination (r = 0.82; P= 0.04).
Grazing Selectivity of Red Abalone Haliotis rufescens Postlarvae on Benthic Diatom Films under Culture Conditions
Authors: Siqueiros‐Beltrones David A. , Voltolina Domenico 
Published: April 2007

AbstractThe gut contents of Haliotis rufescens postlarvae that had grazed on a diatom film grown in PVC buckets were analyzed to determine selectivity in feeding. Species composition and abundances were compared to that of the surrounding film. Diatom samples were oxydized and mounted permanently, or observed directly by the squash technique under phase contrast microscopy. The surrounding flora yielded 111 taxa, while 64 species appeared in the gut contents. A high proportion of Pinnularia biceps v. minor and Navicula incerta (and others) in the gut contents, which were rare or absent from the samples of the surrounding flora, indicated grazing selectivity by the postlarvae. An analysis of similarity confirmed that samples from the gut contents could be grouped together and that they were clearly different from the surrounding flora.
Accelerated Growth, Gigantism and Likely Sterility in Autotransgenic Triploid Mud Loach Misgurnus mizolepis
Authors: Nam Yoon Kwon , Cho Hyo Jong , Cho Young Sun , Noh Jae Koo , Kim Chul Geun , Kim Dong Soo 
Published: April 2007

AbstractTriploidy was induced in two selected lines of autotransgenic mud Ioach Misgurnus mizolepis containing no heterospecific genetic material. Cytological evaluations, including cellular DNA content, chromosome count, and erythrocyte measurement, proved the successful induction of triploidy. Patterns of Southern blot hybridization and tissue distribution of GH mRNA in autotransgenic triploids were similar to those of diploid autotransgenics. The autotransgenic triploids also displayed growth acceleration 22–25 times that of nontransgenic diploids, although the acceleration was relatively modest when compared to their diploid transgenic counterparts (more than a 30‐fold increase). Significantly improved feed conversion was observed in both autotransgenic diploids and triploids, ranging from 1.8 to 2.0 times that in nontransgenics. Autotransgenic triploids were sterile at gonadal level, evidenced by significantly retarded and abnormal gametogenesis. With the persistence of accelerated growth and enhanced feed conversion efficiency, the autotransgenic triploid mud loach may offer economic benefits to aquaculture. Total absence of heterospecific genetic material and sterility may also allay public concern regarding food safety and environmental risk of crossbreeding between transgenics and conspecific populations.