bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Cost of Off‐Flavor
Authors: Engle Carole R. , Pounds Gayle L. , van der Ploeg Martine 
Published: April 2007

AbstractOff‐flavor problems in farm‐raised catfish Ictalurus punctatus increase production costs and pose inventory management problems for catfish farmers. Multiperiod mathematical programming techniques were used to test the effect of 16 different off‐flavor scenarios on expected net returns above variable cost with and without cash flow restrictions. The patterns of off‐flavor incidence had less effect on farm profits than whether or not fish are off‐flavor during certain key months of the year. To be feasible, systems designed to purge off‐flavor from catfish would need to cost less than $0.05 to $0.06/kg (if cash flow is not a consideration) or $0.04/kg to $0.25/ke (with cash flow considerations).
Assessing Noxious Phytoplankton in Aquaculture Systems Using Bio‐Optical Methodologies: A Review
Authors: Millie David F. , Schofield Oscar M. , Dionigi Christopher P. , Johnsen Peter B. 
Published: April 2007

AbstractManagement practices in aquaculture systems contribute to maximum growth of phytoplankton, often resulting in extensive blooms of noxious cyanobacteria. Because periods of oxygen depletion and “off flavor” events correspond to intense algal growth and metabolic activity, accurate identification of algal dynamics and physiological state is important. Current efforts to assess algal assemblages rely upon microscopic evaluation; however, the incorporation of such evaluation into monitoring programs is limited due to the level of skill and training required, the excessive costs and time required to assess algal heterogeneity within/among aquaculture systems, and the lack of information provided concerning physiological state. The distinct biwptical characteristics of the blooms lend themselves to pigment‐based methodologies (pigment and in vivo absorption “signatures”, chlorophyll a fluorescence, multi‐spectral remote sensing) which complement microscopic evaluation and can be implemented into large‐scale monitoring programs. For example, because the key ingredient for success of such programs is the rapid, reliable, and accurate characterization of algal biomass along variable temporal/spatial scales, remotely‐sensed data acquisition most likely will be required. High‐performance liquid chromatography (HPLC)‐derived pigment and in vivo absorption “signatures” can delineate problematic algal phylogenetic groups and physiological states. Further, measurements of chlorophyll a fluorescence provide estimates of phytoplankton absorption, quantum efficiency, and potentially production potential and growth rate. As such, they can be used to confirm the systematic significance of remotely‐sensed data. It would be highly desirable to integrate an evaluation program using bio‐optical methodologies into a geographic information system to allow for integrating, modeling, and predicting parameters of management interest over the scales relevant to aquacultural and water resource management.
Effects of Dietary Protein Concentration on Growth, Survival, and Body Composition of Muskellunge Esox musquinongy and Tiger Muskellunge Esox masquinongy × E. luscius Fingerlings
Authors: Brecka Brian J. , Kohler Christopher C. , Wahl David H. 
Published: April 2007

AbstractGrowth rate, survival and body composition of muskellunge Esox musquinongy (initial mean total length = 125 mm) and tiger muskellunge E. masquinongy × E. lucius (initial mean total length = 115 mm) fed semi‐purified diets differing in protein level from 31 to 40% and 34 to 45%, respectively, were evaluated in 8‐wk trials. The minimum protein level that yielded satisfactory growth rates for muskellunge was 37%, whereas tiger muskellunge growth rates were highest for fish fed a 45% protein diet. Growth differences were caused by changes in protein quantity, not quality, as amino acid ratios were similar for test diets and showed no imbalances among diets. Condition factors for both fishes increased with dietary protein. Survival of muskellunge (73%) and tiger muskellunge (97%) was not pffected by diet type. Body protein increased and fat content decreased in both fishes when fed higher dietary protein. Results suggest that both fishes respond similarly to dietary changes, but that substantial differences exist in protein requirements.
The Aerobiological Pathway of a Fish Pathogen: Survival and Dissemination of Aeromonas salmonicida in Aerosols and its Implications in Fish Health Management
Authors: Wooster Gregory A. , Bowser Paul R. 
Published: April 2007

AbstractThe aerobiological (aerosol) pathway of Aeromonas salmonicida subspecies salmonicida (ATCC 33658) was investigated. Results indicate that viable A. salmonicida can travel as an aerosol/droplet spray at least 104.1 cm (limits of the test chamber used) when carried by air currents. Additionally, viable A. salmonicida was recovered from water exposed to an experimentally generated aerosol/droplet spray of A. salmonicida downwind from the contaminant source. It is possible that viable bacterial aquatic animal pathogens can be spread via the airborne route. This possible route of pathogen introduction could effect current management or system designs, especially when aquaculture systems consist of tanks in close proximity.
Weaning of Wild Young‐of‐the‐Year Winter Flounder Pleuronectes americanus (Walbaum) on a Dry Diet: Effects on Growth, Survival, and Feed Efficiency Ratios
Authors: Lee Gillian W. Y. , Litvak Matthew K. 
Published: April 2007

AbstractWinter flounder Pleuronectes americanus is being developed for aquaculture in Atlantic Canada. Weaning, the switch from a live diet to formulated feed, is a critical stage in the culture of any fish species. In this study, we used wild young‐of‐the‐year stock to determine whether juvenile winter flounder can be weaned from live, cultured Artemia onto dry feed. The dry feed used was originally formulated for turbot Scophthalmus maximus and cod Gadus morhua by BP Nutrition, Stavanger, Norway. The performance of live feed and dry pellets was compared in terms of survival, growth and feed efficiency over three months. We were able to wean wild juvenile winter flounder onto dry feed after one week. Increased specific growth rates and feed efficiency ratios in weaned juveniles indicated that prepared diet was a better food source than Anemia. Survival was not influenced by food type.
Use of High Oleic Corn in Catfish Feeds
Authors: Sugiura Shozo H. , Lovell Richard T. 
Published: April 2007

AbstractHigh oleic corn is a genetic variant that contains more protein, lipid, and oleic acid and less linoleic acid than regular corn. A study was conducted to compare weight gain and feed conversion of year‐1 and year‐3 channel catfish Ietalurus punctatus, and processing yield, body composition and frozen storage stability of year‐3 channel catfish fed high oleic corn and number 2 yellow (regular) corn in extruded production diets. A commercial‐type diet formulated to contain 30% protein and made with regular corn served as a control. A second diet contained high oleic corn in place of regular corn on an equal (air‐dry) weight basis. A third diet contained high oleic corn in substitution for regular corn and part of the soybean meal to limit protein content to 28%, which was equal to that of the control diet. The experimental diets were fed to year‐1 channel catfish (average initial weight 5.1 g) in aquaria for 10 wk and to year‐3 channel catfish (average initial weight 1.07 kg) in 0.04–ha ponds for 14 wk. Substitution of high oleic corn for regular corn on an equal (air‐dry) weight basis provided significant gain (P < 0.01) of year‐1 channel catfish but not of year‐3 fish. Use of high oleic corn diets designed to be equal in protein content did not affect weight gain of either group of fish. Replacement of regular corn with high oleic corn caused a significant (P < 0.01) reduction in linoleic acid but no significant (P > 0.20) increase in oleic acid in the flesh of fish. Proximate body composition, dressing yield, fillet yield, visceral fat, and liver weight were not significantly different among treatments. Sensory scores of fillets frozen for 3 and 6 mo were not significantly different among treatments. Peroxide value, thiobarbituric acid number and free fatty acids increased with frozen storage time but were not different among treatments.
Dietary Phosphorus Requirement of Juvenile Striped Bass Morone saxatilis1
Authors: Dougall David S. , Woods L. Curry , Douglass Larry W. , Soares Joseph H. 
Published: April 2007

AbstractThree experiments were performed in single‐pass, flow‐through systems to determine the dietary phosphorus requirement of striped bass Morone saxatilis. In Experiment 1, three semi‐purified diets were formulated to contain 0.20, 0.40, or 0.60% total phosphorus (entirely from animal protein) and were fed to striped bass having an average initial weight of 321 g. After 14 wk of feeding, significant differences in bone and scale mineralization were found among treatment groups. At a level of 0.40% dietary phosphorus there was a significant improvement of serum calcium (Ca) and tissue mineralization. In Experiment 2, five diets were formulated with graded levels of monopotassium phosphate to yield total phosphorus levels of 0.15 (no P supplementation), 0.35, 0.55, 0.75, and 0.95% and fed to juvenile striped bass initially weighing an average of 7.9 g. After 6 wk, significant improvement in scale and vertebral mineralization occurred when fish were fed diets containing at least 0.55% phosphorus. Improvements were observed in growth, serum phosphorus, incidence of scoliosis, survival, and feed efficiency when the diet contained at least 0.35% P. In Experiment 3, the dietary phosphorus levels fed were 0.30, 0.38, 0.46, 0.54, and 0.62% total phosphorus using graded levels of monopotassium phosphate. Diets were fed to striped bass fingerlings initially weighing an average of 48 g. After 10 wk, significant improvement in scale, vertebral, and dorsal fin mineralization was observed when dietary phosphorus was at least 0.46%. A summary of the broken‐line regression analyses of the data from these experiments indicated that the average total dietary phosphorus level required for optimal growth and mineralization of striped bass was 0.58%.
Supplemental Phosphorus in Practical Channel Catfish Diets1
Authors: Robinson Edwin H. , Jackson L. Scott , Li Meng H. 
Published: April 2007

AbstractThree experiments were conducted to evaluate the need for supplemental phosphorus in the diet of channel catfish Ictalurus punctatus as well as to compare dicalcium phosphate and defluorinated phosphate as sources of supplemental phosphorus. Fingerling channel catfish were stocked into 0.04‐ha earthen ponds at a rate of 1,000 fish/pond (24,700ha). The fish were fed a feed typical of commercial catfish feeds containing 28% protein and 2.8 kcal digestible energy/g once daily to satiation during the growing season (April to October). Fish in experiment 2 were overwintered and fed at a rate of 1% body weight twice weekly when the water temperature exceeded 13 C. The basal diet used in experiments 1 and 2, which contained no supplemental phosphorus, had estimated available phosphorus concentrations of 0.26 and 0.20%, respectively. Dicalcium phosphate was added to provide available phosphorus concentrations of 0.34 and 0.41% for experiment 1, and 0.27 and 0.35% for experiment 2. Diets used in experiment 3 to compare dicalcium and defluorinated phosphates contained 0.40% available phosphorus. Data from experiments 1 and 2 indicated that a concentration of dietary phosphorus of about 0.27% was adequate for maximum weight gain and efficient conversion of feed by channel catfish. However, a concentration of about 0.35% available phosphorus was required for maximum bone mineralization in experiment 2. There were no differences in growth or bone mineralization between fish fed dicalcium or defluorinated phosphate. We conclude that the small increase in bone phosphorus (about 4%) is biologically insignificant, and suggest that 0.3% available phosphorus be adequate for channel catfish raised in earthen ponds. Also, either dicalcium or defluorinated phosphate can be used as a source of supplemental phosphorus in channel catfish diets. However, defluorinated phosphate may be desirable because of its low solubility in water.
A Mammalian Growth Hormone‐Releasing Hormone Increases Serum Growth Hormone Levels and Somatic Growth at Suboptimal Temperatures in Tilapia
Authors: Kelly Anita M. , Kohler Christopher C. , Grau E. Gordon 
Published: April 2007

AbstractThe effects of a mammalian growth hormone‐releasing hormone (GHRH), PrebGRF(1–78)OH (bGHRH), on growth and serum growth hormone (GH) levels were investigated in tilapias Oreochromis mossambicus andO. niloticus × O. aureus. Fish were injected intramuscularly or implanted intramuscularly (Silastic or cholesterol implants) with distilled water, 0.1 μg/kg bGHRH, 1.0 μg/kg bGHRH, 10.0 μg/kg bGHRH, or 100.0 μg/kg bGHRH and compared to untreated controls, fish implanted with 60 mg/kg 17α‐methyltestosterone (MT), or a combination of bGHRH concentrations plus either MT, 0.01 μg/kg of a thyroid hormone (T3), or 0.01 μg/kg of a glucocorticoid (DEX). The bGHRH increased serum GH levels in tilapia maintained at suboptimal temperatures (18 C). Serum GH levels were highest (5.3–0.45 ng/mL) for fish injected with 10.0 μg/kg bGHRH. Fish implanted with a Silastic implant containing 10.0 μg/kg bGHRH had significantly higher (4.35–0.35 ng/mL) serum GH levels than those with an equivalent dosage in a cholesterol implant. The addition of MT, thyroid hormones, and glucocorticoids did not increase serum GH levels above those obtained for fish receiving bGHRH alone. Tilapia reared at suboptimal temperatures and implanted with 10.0 μg/kg and 100.0 μg/kg bGHRH had significantly greater increases in weight and length than control fish. Fish implanted with bGHRH, MT or bGHRH plus MT had significantly higher moisture and protein content, while fat and ash contents were significantly lower than controls or sham‐implanted fish. Fish implanted with bGHRH or bGHRH plus MT had significantly higher gonadosomatic indices than fish implanted with MT alone, shams or non‐treated controls. This study demonstrates that a mammalian GHRH stimulates release of GH, promotes somatic and gonadal growth and may affect reproductive performance in tilapia.
Evaluation of Three Soybean Products in Diets Fed to Juvenile Hybrid Striped Bass Morone saxatilis×M. chrysops
Authors: Brown P. B. , Twibell R. , Jonker Y. , Wilson K. A. 
Published: April 2007

AbstractJuvenile hybrid striped bass Morone saxatilis×M. chrysops were fed practical diets containing graded levels of either solvent‐extracted soybean meal, roasted soybeans, or raw, unprocessed soybeans. Two separate 10‐wk studies were conducted; within each study, there were two separate evaluations of soy products. In the first study, weight gain and feed efficiency of fish fed 45% or higher levels of soybean meal were significantly lower than fish fed the positive control diet, while weight gain and feed efficiency of fish fed 30% soybean meal were not significantly different than fish fed the control diet. Fish fed the lowest level of unprocessed soybean (20%) exhibited significantly depressed weight gain and feed efficiency compared to fish fed the control diet. In the second study, weight gain and feed efficiency of fish fed 40% roasted soybeans were significantly lower than fish fed the control diet, but weight gain and feed efficiency of fish fed 20% roasted soybeans were not significantly lower than fish fed the control diet. In both studies, whole body proximate composition values were significantly different among treatments. Whole‐body lipid concentrations were significantly higher in fish fed certain levels of soy products, but only at levels above those eliciting depressions in weight gain and feed efficiency. A further evaluation of solvent‐extracted soybean meal was conducted with incorporation levels of 20–40% of the dry diet in gradations of 5% with a nutritionally complete mineral premix. Weight gain and feed efficiency of fish fed any level of soybean meal in that study were not significantly different from fish fed a positive control diet. Whole body proximate components were not significantly different between treatments. Unprocessed soybeans apparently have little potential as an ingredient in diets fed to juvenile hybrid striped bass; roasting, or heat treatment, improves their use. Solvent extracted soybean has the potential of supplying the majority of crude protein in diets fed to juvenile hybrid striped bass. Incorporation of complete mineral premixes seems beneficial with higher levels of solvent‐extracted soybean meal.
Low Protein Diets for Channel Catfish Ictalurus punctatus Raised in Earthen Ponds at High Density1
Authors: Robinson Edwin H. , Li Meng H. 
Published: April 2007

AbstractThis study was conducted to evaluate the use of low protein diets for channel catfish Ictalurus punctatus raised in earthen ponds at high density. Fingerling channel catfish were stocked into 0.04‐ha earthen ponds at a rate 24,700 fish/ha and fed experimental diets daily to satiation from April to October 1995. The five diets contained either 32, 28, 24, 20, or 16% crude protein with digestible energy to protein (DE:P) ratios ranging from 8.9 to 16.2 kcal/ g protein. Weight gain was not different among channel catfish fed diets containing 32, 28, or 24% crude protein. Fish fed diets containing 20% or 16% crude protein gained less weight than fish fed the diets containing 28% or 24% crude protein, but not statistically less than the fish fed the 32% crude protein diet. Feed consumption data followed similar trends as weight gain data. Feed conversion ratio increased linearly as dietary protein decreased, but was not significantly different (multiple range test) for fish fed diets containing either 32% or 28% crude protein. There were no differences in survival and hematocrit of fish fed the different diets. No differences (multiple range test) were observed in dressout percentages for fish fed the various diets, but dressout percentage tended to decrease linearly as dietary protein decreased. Visceral fat and fillet fat increased and fillet protein and moisture decreased linearly as dietary protein decreased. Results from this study indicated that dietary protein concentrations as low as 24% are adequate for maximum weight gain of pond‐raised channel catfish fed daily to satiation. Fish fed dietary protein levels below 24% grew relatively well, particularly considering that dietary protein was reduced 40–50% below that typically used in commercial channel catfish feeds. However, dietary protein levels below 24% may increase fattiness to an unacceptable level presumably because of the high digestible energy to protein ratio.
Response of Atlantic Croaker Fingerlings to Practical Diet Formulations with Varying Protein and Energy Contents
Authors: Davis D. Allen , Arnold Connie R. 
Published: April 2007

AbstractAtlantic croaker Micropogonias undulatus is a demersal marine species that is heavily utilized as both a bait and food fish, and which may have commercial culture potential as a bait species. This research sought to initiate the development of practical diet formulations for juvenile grow out and to evaluate the response of this species to controlled culture conditions. Eight practical diets were formulated to evaluate the effects of. 1) increasing lipid levels in a 45% protein diet; 2) dietary protein levels of 45, 40, 35 and 30%; and 3) progressive reduction in dietary energy content of diets with 30% protein. Each diet was offered to four replicate groups of fish having a mean initial weight of 3.8 g over a 7–wk growth trial. At the conclusion of the trial, final mean weights ranged from 17.0 g (410% weight gain) to 8.1 g (210% weight gain) with 100% survival for all dietary treatments. Weight gain and feed efficiency increased with protein content of the diet, with fish fed the 45% protein diet performing the best. Weight gain of fish maintained on the 45% protein diet decreased, but not significantly, as the lipid content of the diet was increased from 8 to 12 or 16%. Feed efficiencies for fish maintained on the diet containing 8% lipid were significantly higher than that of fish maintained on the diet containing 16% lipid. In low protein diets, the replacement of wheat starch with indigestible fiber did not significantly influence growth or feed utilization, indicating that high levels of digestible carbohydrate were not well utilized as an energy source by the fish. The observed results would indicate that growth is optimized on a high protein diet with moderate lipid levels.
Effects of Temperature on Feeding Activity of the White River Crayfish Procambarus acutus acutus1
Authors: Seals C. , Eversole A. G. , Tomasso J. R. , Petrosky B. R. 
Published: April 2007

AbstractFeed consumption by white river crayfish Procambarus acutus acutus in a 56‐d laboratory study increased at a linear rate with water temperature over a range of 5 to 25 C. Feed consumption changed as water temperatures were cycled from 20–8–20 C (0.5 C/d) over a 68‐d period and was the highest at the initial 20 C level and the lowest at 8 C. As water temperature increased, feed consumption rate increased; however, consumption never reached the initial rate at 20 C. Crayfish fed 3% and 6% of body weight were significantly larger than animals fed at 1% of body weight after 8 wk. Feed conversion ratios increased significantly with feeding rate. Based on this laboratory study, white river crayfish feed most effectively when water temperature is ≥ 15 C and the feeding rate is 3% of body weight/d.
Suspended Culture of Doughboy Scallops Mimachlamys asperrima (Lamarck)
Authors: O'Connor Wayne A. , Heasman Michael P. , O'Connor Stephan J. 
Published: April 2007

AbstractTo evaluate the effects of suspended culture on the wet meat weights, reproductive condition and fecundity of doughboy scallops Mimachlamys asperrima, scallops held either in suspended cages or collected from wild stocks on the sea bed were compared over a year. Changes in gonosomatic index (GSI) and macroscopic staging of gonads were similar in both populations; however, after one month, soft body, muscle and gonad weights were heavier in suspended scallops and, with the exception of gonad weight in early summer, remained heavier throughout the year. Fecundity following serotonin‐induced spawning of suspended Mimachlamys asperrima was on average almost twice that of similar sized scallops grown on the sea bed (1.58 and 0.84 million eggs/female, respectively). Suspended scallops surpassed all previous maxima for tissue weights, GSI and fecundity recorded for wild Jervis Bay Mimachlamys asperrima. This indicated that farmers could obtain greater meat yields from suspended rather than reseeded or wild Mimachlamys asperrima and that broodstock to be used in hatcheries may be best obtained from suspended culture.