bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary Zinc Requirement of Oreochromis aureus and Effects of Dietary Calcium and Phytate on Zinc Bioavailability
Authors: McClain W. Ray , Gatlin Delbert M. 
Published: April 2007

AbstractTwo experiments were conducted to determine the dietary zinc requirement of fingerling blue tilapia (Oreochromis aureus) and the effects of dietary calcium and phytate on zinc bioavailability. Purified egg white diets containing graded levels of supplemental zinc were fed to fingerling tilapia in triplicate aquaria for 80 days. No overt signs of zinc deficiency were observed; however, scale and bone zinc concentrations of fish fed the various diets were significantly (P < 0.05) affected and increased linearly as dietary zinc increased until plateauing at 20 mg Zn/kg diet and greater. Based on these data, 20 mg Zn/kg of dry diet was determined to be the minimum dietary zinc requirement of blue tilapia. Purified egg white diets containing 20 mg Zn/kg were also supplemented with 0.5 or 2.0% calcium and 0 or 1.5% phytate in a factorial arrangement to determine the effects of these dietary factors on zinc bioavailability. At this level of supplemental zinc, 1.5% phytate significantly (P < 0.05) reduced zinc bioavailability as reflected in scale and bone zinc concentrations; whereas, dietary calcium did not affect zinc bioavailability. Results from this study establish the dietary zinc requirement of blue tilapia and indicate that higher levels of supplemental zinc should be included in practical feeds to compensate for reduced zinc bioavailability caused by dietary phytate.
Growth and Survival of Larval and Postlarval Smallmouth Bass Fed a Commercially Prepared Dry Feed and/or Artemia Nauplii
Authors: Ehrlich Karl F. , Cantin Marie‐Claude , Rust Michael B. , Grant Blake 
Published: April 2007

AbstractGrowth and survival rates of smallmouth bass (Micropterus dolomieui) were compared for fishes reared from larval stages, for three weeks using different feeding regimes. Diets consisted of a commercial dry diet formulated for larval fishes, the dry diet plus Artemia salina nauplii, and Artemia salina nauplii alone. Smallmouth bass on the three diets showed average daily gains of 0.7, 0.7 and 0.5 mm/day and 11.0, 11.4 and 5.2 mg/day, respectively. Condition factors for the three diets were not significantly different (P > 0.05). Mean survival rates were 39, 85 and 77% respectively.
Paddlewheel Effects on Shrimp Growth, Production and Crop Value in Commercial Earthen Ponds
Authors: Wyban James A. , Pruder Gary D. , Leber Kenneth M. , Burzell L. 
Published: April 2007

AbstractThe effects of continuous paddlewheel operation on shrimp growth, yield and crop value were studied in Hawaii. Six 0.4 ha earthen ponds were stocked with Penaeus vannamei at 25 postlarvae/m2. Three ponds served as controls with no mechanical aeration or mixing. Each of the other three ponds had two 1 hp paddlewheel aerators (3.7 kw/ha) running continuously throughout the five month trial (29 April‐8 October 1986). All other management factors were applied uniformly.Daily water temperature and use were significantly different between treatments. Paddlewheel ponds had lower water temperatures (28.3 vs. 28.5 C) and lower water use (0.8% exchange per day vs. 2.2% exchange per day) than control ponds.Faster shrimp growth in paddlewheel ponds was evident in week 8. At week 14, mean shrimp body weights and growth rates were significantly greater. Shrimp at harvest were 21.2 ± 2.6 g in paddlewheel ponds versus 15.3 ± 2.6 g in control ponds. Mean shrimp production was 2,852 ± 222 kg/ha in paddlewheel ponds compared to only 2,061 ± 558 kg/ha in controls. Mean crop value was $13,719 per pond per crop for paddlewheel ponds versus $9,111 for control ponds. Hence, paddlewheels afforded an increase of 42% in net crop value after subtracting purchase and operating costs.
Effect of Golden Shiners on Plankton and Water Quality in Ponds Managed for Intensive Production
Authors: Ludwig Gerald M. 
Published: April 2007

AbstractWater quality variables and plankton were monitored and compared between ponds that were stocked or not stocked with golden shiners in order to determine what changes occur in the plankton community and water quality of ponds managed for intensive production. Ponds with shiners had significantly lower phosphate and carbon dioxide concentrations and lower carbonate alkalinity than ponds without shiners. No significant difference in nitrite, nitrate, ammonia, temperature, secchi disk readings, or turbidity levels was found between the treatments. The standing crop of phytoplankton was nearly twice as great in ponds with fish. Ponds with fish had significantly fewer copepods but more rotifers than fishless ponds. Although the fish were offered a commercial feed with 29.5% protein and 1.5% crude fat at 3% of their biomass daily, they apparently continued to feed on crustacean zooplankton.
Use of the Nematode Panagrellus redivivus as an Artemia Replacement in a Larval Penaeid Diet
Authors: Biedenbach James M. , Smith Linda L. , Thomsen Tamara K. , Lawrence Addison L. 
Published: April 2007

Abstract Penueus vannumei larvae (P2 through M3) and early postlarvae (<24 h old postlarva) were fed diets consisting of algae‐only, nematodes (Panugrellus redivivus) plus algae or Artemia plus algae. Growth (dry biomass gain) of second and third stage protozoea larvae fed the nematodealgae diet was significantly better than that of larvae fed the Artemia‐algae diet. From the first mysis through the postlarval substage (<24 h old), growth of shrimp fed the nematodealgae diet equalled that of larvae fed the Artemia‐algae diet. All larval substages fed nematodes plus algae accumulated significantly greater biomass than those fed a diet of only algae. Survival and percent metamorphosis of larvae fed nematodes plus algae did not differ significantly from that of larvae fed either Artemia plus algae or algae alone. A nematodealgae feeding regime, which potentially yields growth, survival and metamorphosis equal to that obtained on the standard Artemia plus algae regime, is proposed for P. vannamei.
Stocking Strategies and an Investment Analysis for Producing Penaeus setiferus as a Live Bait‐Shrimp on the Texas Gulf Coast
Authors: McKee David A. , Lawrence Addison L. , Griffin Wade L. 
Published: April 2007

AbstractAn economic and investment analysis was performed to determine the viability of bait‐shrimp farming in Texas. A single pond analysis producing 5–5.5g shrimp always had higher returns above selected cost (RASC) than producing 4–4.5g shrimp. Stocking 0.01g shrimp had a higher RASC than stocking 0.25g, 0.50g or 0.75g shrimp. In the 20 pond analysis, which accounted for marketing considerations, stocking 0.25g shrimp had the highest RASC. The investment analysis, assuming average management, was declared bankrupt by the end of the fifth year. Under “excellent” management the internal rate of return was only 11.7%. It is unlikely that bait‐shrimp farming will become a viable industry in Texas in the near future.
A Standard Reference Diet for Crustacean Nutrition Research. II. Selection of a Purification Procedure for Production of the Rock Crab Cancer irroratus Protein Ingredient
Authors: Castell John D. , Kean J. C. , McCann D. G. C. , Boghen Andrew D. , Conklin Douglas E. , D'Abramo Louis R. 
Published: April 2007

AbstractObtaining reliable results from comparative crustacean nutrition studies requires a dietary reference protein which is available world‐wide and is nutritionally optimal for growth and survival. Traditional protein sources include “vitamin free” casein, egg albumin, whole egg protein, soybean protein, and others. These have proven to be inadequate for juvenile lobster (Homrus americanus). Purified rock crab (Cancer irroratus) protein is proposed to be nutritionally superior to casein for inclusion in semi‐purified lobster diets.Eighteen week feeding trials with juvenile H. americanus were conducted to compare diets containing protein obtained from rock crabs (Cancer irroratus), and produced by several different purification processes with a control diet having casein as its primary protein source. Diets containing purified rock crab protein were found to be superior to the control diet. Among the differently derived purified rock crab protein products, the precooked, isopropanol‐purified was the most effective dietary ingredient.
A Standard Reference Diet for Crustacean Nutrition Research.: IV. Growth of Freshwater Crayfish Cherax tenuimanus
Authors: Morrissy Noel M. 
Published: April 2007

AbstractJuvenile Australian freshwater crayfish (Cherax tenuimanus) were individually housed in an experimental battery system and fed HFX CRD 84 and BML 81 S, two proposed standard reference diets for studies of crustacean nutrition. The HFX CRD 84 diet was accepted more readily than the BML 81 S diet. After 100 days, mean weight gain of marron fed the HFX CRD 84 diet was significantly greater than that of those fed the BML 81 S diet. Growth rate, measured 118 percent weight pin per ecdysis, declined during three successive 50 day periods. Growth on the proposed reference diets ranged from 16 to 33% of that achieved with pond raised marron of similar age. Both diets may be useful in the development of species specific modifications relative to nutrient composition.
Polyphosphorylated L‐ascorbic Acid: A Stable Form of Vitamin C for Aquaculture Feeds
Authors: Grant Blake F. , Seib Paul A. , Liao Ming‐Long , Corpron Kenneth E. 
Published: April 2007

AbstractA protected form of vitamin C, L‐ascorbyl‐2‐poly phosphate (APP), was tested for safety and efficacy in fishes. Phosphorylation of the 2‐hydroxyl group protected the 2,3‐enediol of L‐ascorbic acid against oxidation. When APP was added to feed, about 15% of its vitamin C activity was lost during milling and storing 5–7 d at ambient temperature. Stability of APP in pelleted feeds at 25 or 40 C was up to 83 times or 45 times greater than that of ascorbic acid (AA), respectively. In later tests, trout feed mash, steam‐pelleted in triplicate, frozen, and shipped on dry ice before analysis, had 46% loss of AA and no apparent loss of APP.With 16% milling loss (highest detected in trout feeds assayed in initial tests) and 22% storage loss after 90 d, conservative APP mix rates were estimated. Mixing 153 g L‐ascorbate‐equivalent as APP per metric ton of airdry ingredients (153 ppm) would give 128 ppm in the finished feed after steam‐pelleting and 100 ppm after 60–90 d storage at 40 C.Low‐temperature extrusion of Oregon‐Moist salmon feed reduced AA slightly. Ascorbic acid oxidized in frozen storage and while thawing and, after 12 h at room temperature, only trace amounts remained. Ascorbyl‐2‐polyphosphate at 0.05 to 0.2 times that of equimolar AA in casein‐base or practical feeds supported long‐term growth and development in rainbow trout and other fishes. Trout feeding trials with practical feeds in actual production regimens documented APP activity at growth rates approaching the maximum for trout farming.Corrected for greater stability, APP antiscorbutic activity appeared to be comparable to that of AA on a molar‐equivalent basis. Similarly, apparent equimolar activity was inferred from estimated equilibrium levels of liver, kidney, and whole‐body AA and L‐ascorbyl‐2‐sulfate (AS) after prolonged APP use in trout feeds.Fathead minnow growth and reproduction in egg‐to‐egg life‐cycle tests also confirmed APP safety and efficacy as a stabilized source of vitamin C for feeds.None of the typical lesions of scoliosis, malformed gill lamellae, and crenulated opercles, nor conditions of poor health, anorexia, and eventual torpor seen in vitamin C‐deficient controls occurred in trout fed APP. No liver pathology was evident in trout fed APP for 252 d at 1.7 to 3.3 times the National Research Council's recommended vitamin C (equivalent) rates.
Growth and Survival of Intrastrain and Interstrain Rainbow Trout (Oncorhynchus mykiss) Triploids1
Authors: Guo Ximing , Hershberger William K. , Myers James M. 
Published: April 2007

AbstractTriploid rainbow trout exhibit improved survival and extended growth during sexual maturation, compared to their diploid counterparts. However, there have been few benefits demonstrated prior to sexual maturation. This study was undertaken to investigate the possibility of improving growth and survival parameters in triploids through interstrain crosses. Triploids were induced by heat shocking fertilized eggs from intra‐ and interstrain crosses of two rainbow trout strains. The four triploid groups and their diploid counterpart groups were reared to 233 days post‐hatching and analyzed for growth and survival characteristics.Compared with diploids, triploids had significantly (P < 0.05) higher mortalities during the first 100 days post‐fertilization, primarily just prior to and after hatching. However, during the remainder of the study triploids exhibited significantly (P < 0.05) lower mortalities than diploids. During the first 50 days of rearing all four triploid groups were significantly shorter and lighter than their diploid counterparts. The growth of the triploid groups later in the study varied considerably. At the conclusion of the rearing phase, one interstrain triploid group was significantly (P < 0.05) longer than its diploid counterpart, although not significantly heavier. The other triploid groups were either significantly smaller than, or equal to the diploids. Analysis of variance indicated that the growth of triploid rainbow trout was significantly affected by maternal strain effects. These results suggest that the use of specific strains and crosses may improve the growth of triploid rainbow trout.
An Evaluation of a Leuteinizing Hormone‐Releasing Hormone Analog to Induce Spawning of Channel Catfish Ictalurus punctatus
Authors: Busch Robert L. , Steeby James A. 
Published: April 2007

AbstractThe leuteinizing hormone‐releasing hormone (LH‐RH) analog, DAla6DesGly10 LH‐RH‐ethyl amide, delivered by intraperitoneal or intracranial injection was an effective agent for the induced spawning of channel catfish (Icrulurus punctatus) held in aquaria. A daily dose of 100 μg LH‐RH analog (LH‐RHa) per kg fish body weight was recommended as the dosage schedule of choice, but daily doses as low as 1 cg LH‐RHa per kg fish body weight induced spawning of channel catfish. LH‐RHa was as good or better than human chorionic gonadotropin or carp pituitary to induce spawning of channel catfish in aquaria. Sham‐injected (control) channel caffish spawned in this study contradicting observations in earlier studies.
Effect of Feeding Rate on Growth and Feed Conversion of Florida Red Tilapia Reared in Floating Marine Cages
Authors: Clark John H. , Watanabe Wade O. , Ernst Douglas H. , Wicklund Robert I. , Olla Bori L. 
Published: April 2007

AbstractAn experiment was conducted to investigate growth, survival and feed conversion of Florida red tilapia reared in floating cages in seawater under different feeding regimens. Twenty‐four cages (1 m3) were anchored in a sea pass on Great Exuma, Bahamas, and each was stocked with 300 juvenile, monosex males (10 g mean weight). Growth was monitored every 14 days for 84 days. Fish were fed daily a floating pelletized diet (32% protein) at 4 programed rates representing 50, 70, 90, and 110% of the estimated satiation rate, ad libitum, and by demand feeders, with each treatment comprised of 4 replicate cages.Final mean weight was significantly lower for the 50% treatment (94.1 g) than for all other treatments (range = 121.8–155.7 g). Final mean biomass per cage ranged from 24.2 to 39.4 kg/m3, and survival ranged from 98.2 to 99.8%.Mean specific growth rate was significantly lower under the 50% programed feeding treatment (2.42%/day) than for all other treatments (range = 3.15–3.56%/day) while feed conversion ratios (dry weight/wet weight) were significantly lower under the 50% (1.57) and 70% (1.68) programed feeding treatments than under all other treatments (range = 1.98–2.26). Thus, maximum growth was achieved at feeding rates near satiation while feed conversion was improved at lower feeding rates. Under demand feeding, growth and feed conversion were not significantly different than those of the ad libitum, 100%, and 90% treatments.
Diversification of Crawfish Management Schedule1
Authors: Eversole Arnold G. 
Published: April 2007

AbstractSix 0.02 ha ponds were used to evaluate crawfish production and standing crop biomass of rice forage in ponds managed on a standard (control) and delayed (experimental) schedule over a two year production cycle. Delayed schedule followed the same sequence of events except the management activities were delayed approximately one month. Control and experimental ponds had statistically similar amounts of forage. No statistical difference was detected in crawfish production between the management schedules or between production years; however, analysis revealed a significant treatment × year interaction. Overall average crawfish production was 986 kg/ha. Variation in crawfish production is explained within the context of annual temperature variations and differences in population density.
Quality Evaluation of Four Sources of Brine Shrimp Artemia spp.1
Authors: Webster Carl D. , Lovell Richard T. 
Published: April 2007

AbstractA study was conducted to compare fatty acid composition, hatching quality, and size of nauplii from four commercial sources of brine shrimp (Artemia spp.) cyse: China (CH), Colombia (COL), Great Salt Lake (GSL), and San Francisco Bay (SFB). The CH brine shrimp had a comparatively high percentage of 20:5(n‐3) fatty acid (eicosapentaenoic acid or EPA), an essential fatty acid for most Iarval fishes, which was 10.4% of the total lipids. The COL, GSL, and SFB sources of cysts contained comparatively low percentages of EPA, 2.9, 1.2, and 1.6%. respectively. Hatching quality was determined by hatching cysts in salt (NaCl) water with a specific gravity of 1.02 at 27 C for 42 h. The COL cysts had the fastest hatching rate, with 50% of the cysts hatching in 13.4 h, while CH cysts hatched at the slowest rate, requiring 25.6 h for 50% of the cysts to hatch. Total percentage hatch was not significantly different among the SFB, COL, and GSL sources, with an average hatching percentage of 84.5, while CH cysts had a significantly lower total percentage hatch of 67.5. The SFB source produced the greatest number of nauplii (1.6 ± 105 per g of cysts) with the smallest length (382 μm), while CH produced the smallest number (8.7 ± 104) with the greatest length (500 μm). These results indicate that there is great variation in nutritional quality, hatching quality, and size of nauplii among commercial sources of brine shrimp cysts, and each of these criteria should be considered in selecting brine shrimp in a development of a feeding strategy for larval culture of a particular species.
The Economics of Intensifying Catfish Production: A Production Function Analysis1
Authors: Nerrie Brian L. , Hatch L. Upton , Engle Carole R. , Smitherman R. Oneal 
Published: April 2007

AbstractYields of channel catfish in the United States have increased as a result of higher levels of stocking, feeding and aeration. A Cobb‐Douglas production function was estimated using survey data from 66 catfish ponds in West‐Central Alabama to determine if further intensification of catfish production in West‐Central Alabama would be profitable.Feed, capital, stocking rate, and length of production period explained most of the variation in yield. Values of the marginal products for feed, stocking rate and capital were consistently higher than input costs during the study period. Profit‐maximizing levels of input use were higher than the levels of inputs used in West‐Central Alabama during the study period. Results indicated that more intensive use of production inputs would increase yield and profits. However, careful interpretation of these results requires consideration of non‐profit factors such ns cash Row and risk as well as the specific nature of the data used to develop the production relationship. The method utilized in this study can generally be applied to any aquaculture production system, but the recommendation for more intensive input use is specific to the pond data collected for this study.
Principles of Siphons
Authors: Garrett Roger E. 
Published: April 2007

AbstractA simple siphon raises water over a crest and discharges it at a lower level. As water flows through a siphon, energy due to pressure and elevation is either lost to pipe friction or converted to velocity energy. For most practical siphons, between 50 and 75% of the elevation energy available to drive flow will be converted to velocity energy.A standpipe covered with a dome will begin to siphon when the standpipe flows full. During siphoning, the flow rate may be several times higher than the flow through an uncovered standpipe of the same size. Furthermore, the covered standpipe can be designed to lower the water level to a point below the top of the standpipe before siphoning is allowed to stop.Flow into the covered standpipe can be drawn from the bottom of the reservoir by extending the skirt of the dome. A vent tube allows easy adjustment of the elevation at which air enters the dome and siphoning stops. Flow rate and water level required to start the siphon depend on the pipe diameter. Some flow through the standpipe will occur before siphoning begins. Flow into the reservoir must be greater than the flow required to start siphoning. Maximum flow through the standpipe during siphoning depends on pipe diameter and the elevation energy driving the flow.Adding a trap to the outlet of the covered standpipe eliminates the leakage flow prior to the start of siphoning. When air bubbles out the trap at the end of the standpipe, pressure inside the dome is released suddenly allowing the water level to jump above the critical level needed to start siphoning. For reliable operation, the crest height of the trap should be about equal to one diameter of the standpipe. The vent tube opening must be below the top of the standpipe to prevent premature overflow of the standpipe. Because a trapped outlet siphon has no minimum flow limit, the standpipe can be sized to carry any maximum flow.While the trapped outlet siphon eliminates low rate leakage flow prior to the onset of siphoning, the height differential between the start and stop of siphoning cannot be as small or as easily adjusted as with a covered standpipe without a trap. The simple siphon is convenient for some applications, but it does not lend itself to automatic cycling operation. The choice depends on the needs of the situation.
Growth and Bone Development in Channel Catfish Fed 17‐α‐Methyltestosterone in Production Ponds
Authors: Gannam A. L. , Lovell R. T. 
Published: April 2007

AbstractEffects of feeding 17‐α‐methyltestosterone (MT) to channel catfish (Icralurus punctatus) grown to harvestable size in earthen ponds were examined. Channel catfish fingerlings (mean weight, 14.4 g), stocked in 0.04 ha ponds (7,410 fish/ha) were fed diets containing MT at concentrations of 0, 2.5, and 10 mg/kg for 123 days. Weight gain by fish fed the control diet (0 MT) was higher (P < 0.05) than that of fish fed the treated diets. Increasing the dietary concentration of MT reduced weight gain further (P < 0.05). Both male and female fish fed MT had enlarged and thickened heads, and their skins were dark. Their dorsal and pectoral spines were short and the tips, which are normally very sharp, were soft and blunt. Weight of the rib bones per unit of length decreased (P < 0.05) as MT was added to the diet. Breaking strength of the ribs (force required to break the bone at its midpoint) measured by an Instron shear press, was less (P < 0.05) for fish fed MT than for control fish. The ratio of calcium to phosphorus in bones was lower (P < 0.05) in fish fed MT. These results indicate that feeding MT at these doses (2.5 mg/kg or above) to channel catfish suppresses growth rate and reduces size and strength of bones.