bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acute Toxicity of 5% Non‐Synergized Emulsifiable Rotenone to White River Crayfish Procambarus acutus acutus and White Perch Morone americana
Authors: Wujtewicz Donald , Petrosky Bernard R. , Petrosky Dorene L. 
Published: April 2007

AbstractAnnual drawdown of crayfish culture ponds to plant forage crops also serves to eradicate most predaceous finfish. Without annual drawdown predaceous fish populations may reach numbers that can significantly reduce the crayfish crop. Frequent drawdown may not be feasible or desirable in some management schemes. Evidence in the literature suggests that differential toxicity of rotenone would allow removal of fish without harming crayfish in the same pond. In the current study, laboratory and in situ acute toxicity bioassays (96 h) were conducted with 5% non‐synergized emulsifiable rotenone to define the maximum non‐lethal concentration (LC100) for white river crayfish Procambarus acutus acutus and the minimum lethal concentration (LC100) for white perch Morone americana. Six concentration levels of rotenone formulation were tested in each of six toxicity trials with crayfish using dechlorinated tap water at 21–25 C. LC0 (compensated for control mortality) was determined to be 3.0 mg/L. Significant crayfish mortality began at 4.0 mg/L. Acute toxicity to white perch was anticipated to be within recommended concentration levels on product label for similar fish, and was corroborated by laboratory bioassay (LC100 of 0.15 mg/L). Both species were then tested together in laboratory aquaria utilizing pond water at room temperature. Concentration levels of 0.05–2.5 mg/L killed all white perch with no crayfish mortality. In the final phase of the study a 1.0 mg/L concentration of rotenone was applied to a pond containing both species held in cages. All white perch were dead within 24 h; no crayfish mortality was observed for the 96‐h duration of the trial. It may therefore be possible to use this rotenone formulation to control white perch and other finfish in active crayfish culture ponds.
Reproductive Performance of Different Sized Wild and Pond‐reared Penaeus paulensis Females
Authors: Cavalli Ronaldo O. , Scardua Marcos P. , Wasielesky Wilson 
Published: April 2007

AbstractThe present study analyzes the reproductive performance of three size classes of wild (average weight of 46.5, 55.0, and 63.2 g) and three size classes of pond‐reared (18.4, 21.3, and 25.1 g) Penaeus paulensis females. Unilaterally eyestalk ablated females were placed for 70 d in 3.6 m diameter tanks at 6 individuals/m2 and a 1.2:1 female‐male ratio. Number of spawns, eggs, nauplii, fertilization and hatching rates were recorded every second day. The length of unfed protozoea I larvae was also recorded. Larger broodstock shrimp tended to suffer higher mortality rates. Smaller, pond‐reared females started spawning at 28.2 ± 4.1 g. The number of eggs and nauplii per spawning event were not significantly different between experimental groups (P > 0.05), but due to their higher spawning frequency, small wild females (46.5 ± 3.7 g) outperformed medium (55.0 ± 1.8 g) and large ones (63.2 ± 7.0 g). No relationship between protozoea length and spawner size was found. Optimum size for the maturation of wild P. paulensis females was estimated to be from 30 to 60 g. It is suggested that the use of this size range can potentially enhance nauplii production of P. paulensis.
Effect of Dietary Vitamin C on Weight Gain, Tissue Ascorbate Concentration, Stress Response, and Disease Resistance of Channel Catfish Ictalurus punctatus1
Authors: Li Meng H. , Wise David J. , Robinson Edwin H. 
Published: April 2007

AbstractJuvenile channel catfish Ictalurus punctatus (average initial weight, 6.5 g/fish) were fed twice daily to apparent satiation with practical‐type diets containing 0, 50, 150, or 250 mg supplemental vitamin C/kg from L‐ascorbyl‐2‐polyphosphate for 10 wk under laboratory conditions. At the end of the feeding period, one half of the fish were stressed for 2 h by confinement and both stressed and nonstressed fish were exposed to a virulent strain of Edwardsiella ictaluri. Weight gain and feed conversion efficiency were lower for fish fed the basal diet than those fed diets containing supplemental vitamin C. No differences were observed in weight gain and feed conversion among fish fed diets containing supplemental vitamin C. There were no differences in feed consumption and survival (prior to experimental infection) among treatments. No vitamin C deficiency signs except reduced weight gain were observed in fish fed the basal diet. Serum cortisol concentrations were higher in stressed fish than in non‐stressed fish. Dietary vitamin C level had no effect on serum cortisol concentration. As dietary vitamin C increased, ascorbate concentration in serum and liver increased. Confinement stress had no effect on serum and liver ascorbate concentrations. Cumulative mortality of channel catfish 21 d subsequent to experimental infection with E. ictaluri was higher for stressed fish than for nonstressed fish. Regardless of stress or nonstress, overall mortality for fish fed the basal diet was lower than the fish fed diets containing supplemental vitamin C. There were no differences in post‐infection antibody levels among treatments or between stressed and nonstressed fish. Results from this study indicate that channel catfish require no more than 50 mg/kg dietary vitamin C for normal growth, stress response, and disease resistance.
Phosphorus Budgets for Channel Catfish Ponds Receiving Diets with Different Phosphorus Concentrations
Authors: Gross Amit , Boyd Claude E. , Lovell Richard T. , Eya Jonathan C. 
Published: April 2007

Abstract.Phosphorus budgets were prepared for channel catfish Ictalurus punctatus ponds at Auburn, Alabama, that received one of five diets ranging from 0.60 to 1.03% phosphorus. Fish production did not differ (P > 0.05) among diets. There were few differences among treatments with respect to soluble reactive phosphorus, total phosphorus, and chlorophyll a concentrations or gross primary productivity. Phosphorus loss in effluents when ponds were drained for harvest did not differ among treatments (P > 0.05). Phosphorus removed from ponds in fish at harvest and the amounts of phosphorus adsorbed by bottom soils increased as dietary phosphorus concentration increased (P < 0.05). Low‐phosphorus diets did not decrease phytoplankton productivity or improve effluent quality. Uptake of phosphorus by bottom soils is a major factor controlling phosphorus concentrations in pond water. Low‐phosphorus diets can be beneficial in catfish pond management by reducing the phosphorus load to bottom soils and conserving their ability to adsorb phosphorus.
Stunting of Coho Salmon Oncorhynchus kisutch Parr Rearedin Wastewater‐Seawater Ponds
Authors: Allen George H. 
Published: April 2007

Abstract.After entering saline water coho salmon Oncorhynchus kisutch parr often cease to grow (stunt) and many stunts eventually die. Stunted coho parr occurred in an experimental wastewater‐seawater smolt production system constructed in 1971 on the northern arm of Humboldt Bay, Arcata, California, USA. In 1991 many stunted parr (1990 brood) were noted during transfer of juveniles from a 0.02‐ha shaded pond used for summer rearing (July‐December) to a 0.15‐ha unshaded pond used in winter‐spring rearing (January‐May). The cohort suffered a 42% mortality during summer rearing in low salinity water (7 ppt) but deaths due to stunting could not be estimated. When the summer parr were transferred for winter rearing to 15 ppt salinity water, a total mortality of 15% was nearly all related to stunting. A small sample of stunted, but otherwise normal‐appearing, parr found in smolt out‐migrant traps was retained for an additional year of rearing (February 1992—January 1993). There was a 29% survival in these stunts, with survivors attaining an average fork length of 16 cm (range 12–21 cm). The survivors exhibited parr, pre‐smolt, and “smolt‐like” external appearances. Five groups of 1990‐brood smolts were released into Humboldt Bay. They had rates of return to their point‐of‐release (South Pond) similar to other brood years released from the Arcata ponds and other northern California hatcheries. This suggested that whatever produced stunting in the 1990 brood acted independently of endocrinological or physiological factors that produce mortalities in smolts after entering saline water.
Evaluation of Trap Density and Type for Harvesting Crawfish Procambarus spp. from Small Ponds
Authors: Huner Jay V. 
Published: April 2007

AbstractHarvested crawfish were stocked into 0.15‐ha earthen ponds in March and May at rates of 114, 227, and 455 kg/ha to evaluate the effects of trap density, 27 and 54 traps/ha, on their recapture over 14 d following 3 d of acclimation. Two‐funnel, stand‐up pillow traps and three‐funnel pyramid traps were compared. About 39% and 55% of stocked crawfish were recovered in March and May, respectively. There was considerable growth of those crawfish. Overall catch with both trap densities was equivalent in March but the higher trap density caught 1.3 times more crawfish in May. Pyramid traps caught 1.5–1.9 times more crawfish than pillow traps.
Age‐Related Sperm Quality of Captive Striped Bass Morone saxatilis
Authors: And Verapong Vuthiphandchai , Zohar Yonathan 
Published: April 2007

Abstract.Three groups of captive‐reared striped bass Morone saxatilis ages 1, 3 and 12 yr, were examined for age‐related changes of sperm characteristics including short‐term storage. All groups had similar ranges of the following parameters (mean× SEM): expressible milt (5.6× 0.5 mI/kg body weight (BW) to 7.5× 2.1 mL/kg BW), percentage of motile sperm (55× 6% to 60× 2%), duration of sperm motility (69× 3 sec to 72× 5 sec) and percentage of viable sperm (91× 2% to 93× 2%). Compared to the 1 and 12‐yr‐old fish, the 3‐yr‐old fish produced the greatest number of spermatozoa (1,190× 370× 109 spermatozoa/kg), sperm concentration (120× 8 × 109 spermatozoa/mL) and spermatocrit (74× 4%). In addition, during short‐term storage at 4 C, extender‐preserved sperm samples of the 3‐yr‐old group showed a significantly higher (P < 0.05) percentage of motile sperm and duration of sperm motility, compared to the other two groups. This suggests that short‐term storage may be affected by the age of the male fish. Sperm longevity of the 3‐yr‐old group was successfully maintained for as long as 15 d, longer than that of the 1‐yr‐old group (9 d) and 12‐yr‐old group (7 d). Overall, the 3‐yr‐old fish appeared to have superior sperm quality than the 1 or 12‐yr‐old fish based on higher sperm production and increased sperm longevity.
Acute Toxicity of Ammonia and Nitrite to White Shrimp Penaeus setiferus Postlarvae
Authors: Alcaraz Guillermina , Chiappa‐Carrara Xavier , And Verónica Espinoza , Vanegas Ceclilia 
Published: April 2007

Abstract. Penaeus setiferus postlarvae were exposed to acute levels of ammonia, nitrite, and to a mixture of both by a short‐term static method, The 24h, 48‐h and 72‐h LC50 values for un‐ionized ammonia were 1.49, 1.21 and 1.12 mg/L NH3‐N (un‐ionized ammonia as nitrogen), and 11.55, 9.38 and 8.69 mg/L ammonia‐N (un‐ionized plus ionized ammonia as nitrogen). The 24‐h, 48‐h and 72‐h LC50 values for nitrite were 268.06, 248.84 and 167.33 mg/L nitrite‐N (nitrite as nitrogen). Nitrite was much less toxic than ammonia. The joint effect of ammonia and nitrite on the postlarvae was synergistic at 48‐h exposure and antagonistic after 72 h. Postlarvae of P. setiferus may be considered as organisms sensitive to ammonia and nitrite.
Feeding Levels of the Southern Brown Shrimp Penaeus subtilis in Response to Food Dispersal
Authors: Nunes Alberto J. P. , Parsons G. Jay 
Published: April 2007

AbstractThe development of efficient feed management strategies in shrimp farming involves the investigation of aspects related to time of feed distribution, feeding rates, feeding frequency, and feed dispersal methods. This work examined the feeding levels of Penaeus subtilis in response to food dispersal method under semi‐intensive culture conditions. The study consisted of two treatments: 1) a uniform feed dispersal over the culture area, and 2) concentration of feed in 0.2‐m2 circular feeding trays. For each, three 105‐m2 rectangular enclosures were installed in a single shrimp grow‐out pond and stocked with P. subtilis at a density of 14.29 postlarvae/m2. Shrimp were fed daily at 0600, 0930 and 1430 h and sampled 30 min after feed distribution at 12‐d intervals. After collection, shrimp weight was determined, their stomachs dissected and weighed. A total of 2,160 stomachs of P. subtilis were collected during a 89‐d rearing cycle. Relative occurrence of artificial versus natural food in stomach contents was determined by stable carbon isotope mass spectrometry. Density of polychaetes in the substrate was monitored at each sampling period. After harvest, sediment samples were collected for physical and chemical analyses. In general, differences in shrimp growth between feeding methods were not significant. Final shrimp survival rates were between 69.0 ± 6.9% and 71.9 ± 3.7%. Stomach content weight of P. subtilis was significantly higher when feed was broadcast than for feed concentration. Average stomach content weight remained constant throughout the rearing cycle, although progressive increases in feed Occurrence were detected in P. subtilis diet. No periodicity in food intake along sampling periods could be related to increases in shrimp carapace length. Food intake was significantly lower at 0600 h than at 1430 h and at 0930 h, respectively. In both treatments, over half of the food contained in the stomach contents of shrimp was derived from artificial food. Sediment chemical analysis indicated statistically lower levels of sodium in the pond bottom of concentrated treatment. However, no short‐term detrimental effects were detected on sediment chemical quality. Results indicated that feed broadcasting resulted in a greater access and a higher consumption of food among the cultured shrimp population, a lower number of empty stomachs, and a greater occurrence of artificial food in P. subtilis stomach contents.
Growth and Mineral Absorption by Striped Bass Morone saxatilis Fed a Plant Feedstuff Based Diet Supplemented with Phytase
Authors: Papatryphon Elias , Howell Rachel A. , Soares Joseph H. 
Published: April 2007

AbstractTwo experiments were conducted to determine the effects of phytase on growth, apparent phosphorus (P), calcium (Ca), iron (Fe), zinc (Zn), magnesium (Mg), and copper (Cu) absorption, and apparent protein digestibility by striped bass Morone saxatills fed a high phytate diet. In experiment one, four diets with graded levels of phytase supplementation, 0, 500, 1,000, and 2,000 phytase units/kg of diet (PUkg), and a diet supplemented with inorganic P (positive control, total P, 0.73%; phytin P, 0.35%) were assigned to duplicate tanks, and were fed to fingerling striped bass for 16 wk. A digestibility trial was conducted at weeks 16–18, using 0.5% Cr2O3 as an indigestible marker in the diets. Phytase was sprayed post‐extrusion on the basal diet (P‐total, 0.58%; P‐phytin, 0.35%). Experiment two consisted of a 2‐wk digestibility trial with three treatments: 0 (basal; total P, 0.73%; phytin P, 0.34%), 1,000, and 2,000 PU/kg, assigned to four, three and three replicate tanks respectively. Each tank contained an average of 20 striped bass (mean weight: 400 9). The diet used was similar to the basal in experiment one, which was modified to have low essential trace mineral concentrations, in order to increase the sensitivity of the assay. In experiment one, significant improvements (P≤ 0.05) in growth, feed conversion ratios, and vertebral and scale ash concentrations of fish at the end of the experiment were achieved with either added inorganic P or increasing phytase supplementations. Results from both digestibility trials indicated that P absorption was improved with the addition of at least 500 PUkg. Absorptions of Ca and Fe were significantly increased (P≤ 0.05) and Zn absorption marginally improved (P≤ 0.06) when at least 2,000 PU/kg was supplemented to the diet. Protein digestibility, Mg and Cu absorption were not significantly different in any treatment. Whole carcass P retention was significantly improved with the addition of 1,000 PU/kg, and 2,000 PU/kg, when compared to fish fed the basal diet, 500 PU/kg and positive control treatments. Results from these experiments indicate that phytase supplementation of at least 1,000 PU/kg is adequate to maintain growth rate and health comparable to an inorganic P supplemented diet. In addition, bioavailability and utilization of P is increased with increasing phytase supplementation. Diet supplementation of 2,000 PU/kg increased Ca, Fe, and Zn digestibility by striped bass fed a high phytate diet.
A Dynamic, Stochastic Model of a Land‐Based Summer Flounder Paralichthys dentatus Aquaculture Firm
Authors: Zucker David A. , Anderson James L. 
Published: April 2007

AbstractExploring the possibilities for commercial aquaculture has historically concentrated on reducing production uncertainty by focusing on an animal's biology and the engineering of the production facility. However, the aquaculturist faces both production and market uncertainty, both of which may significantly affect the economic feasibility of a production facility. We developed a dynamic stochastic model to compare alternative production and marketing scenarios and used the net present value of returns to evaluate the scenarios. Based on the model and the scenarios we examined, firms producing summer flounder Paralichthys dentatus are unlikely to be profitable unless they locate near and use a source of salt‐water, sell their product predominately to sushi chefs (or other premium market outlets) who desire medium‐sized live fish, and engage in strategies that account for market dynamics.
Disinfection, Microbial Community Establishment and Shrimp Production in a Prototype Biosecure Pond
Authors: Bratvold Delma , Lu Jingrang , Browdy Craig L. 
Published: April 2007

AbstractPlankton community establishment and shrimp production in a prototype biosecure pond were compared to three control ponds. The biosecure pond was enclosed and intake water was disinfected, while control ponds were neither enclosed nor disinfected. All ponds were managed with no water exchange and stocked with 100 postlarvae/m2, Litopenaeus vannamei. Residual oxidant concentrations in the biosecure pond dropped rapidly after cessation of chlorinated water addition. This was followed by a sharp increase in water column bacterial abundance, after which the pond was fertilized and inoculated with cultured Chaetocerous gracilis. After crash of the initial C. gracilis bloom in the biosecure pond, this species was not observed again. Following initial large fluctuations in biosecure pond bacterial abundance, phytoplankton biomass, oxygen consumption and nitrification rates, these parameters appeared to stabilize at levels similar to the control ponds. Early season compositional differences in phytoplankton, zooplankton, and bacterial communities were observed. No differences were seen in late‐season phytoplankton and bacteria; however, zooplankton biomass tended to be lower in the biosecure pond than in the control ponds throughout the season. Shrimp production in all ponds was greater than 9,000 kg/ha. Production in the single biosecure pond was not a significant outlier compared to production in the triplicate control ponds.
Development of a Model for Describing Accumulation of Color and Subsequent Destruction by Ozone in a Freshwater Recirculating Aquaculture System
Authors: Christensen J. Michael , Rusch Kelly A. , Malone Ronald E 
Published: April 2007

AbstractThe purpose of this study was to develop a mathematical model to assist in the determination of design numbers for color destruction by ozone as a function of feed rate. A mass balance model was developed that takes into account methods of introduction and removal of color, including removal by ozone. Because direct measurement of color mass or concentration is difficult, a representative unit was developed during this study called the color mass equivalent (CME). The CME represents a direct measurement of absorbance at 436 nm, which is a unitless measurement, multiplied by the system volume. The CME is directly proportional to the true concentration of color causing compounds at that wavelength. Once the model was developed, two studies were run to test the model. A 1,500‐L recirculating fish system was set up with a 57‐L bead filter and six 1‐L fluidized sand beds. Approximately 45 kg of channel catfish Ictalurus puncfatus were placed in the system and fed 0.25 kg of 32% protein feed per day (0.55% body wt.). Once the system reached stable conditions, the system was flushed with clean water and samples were taken to estimate the accumulation rate of color in the system. After 5 wk, an ozone unit was activated and samples were taken to determine the destruction rate for color. Once an accumulation rate had been determined, a second study was performed to corroborate this value. The same ozone unit was installed on a 5,000‐L recirculating fish system being fed 0.49 kg per day with a 171‐L bead filter. Samples were taken to determine the destruction rate for color. The accumulation rate for color was 12.6 CME/kg feed and the destruction rates were 1.7 CME/g O3 in the first study and 0.82 CMWg O3 in the second study. This calculates to a range of 7 to 15 g O3/kg feed to remove the color produced by the feed.
Utilization of Deoxynivalenol‐Contaminated Hard Red Winter Wheat for Shrimp Feeds1
Authors: Trigo‐Stockli Dionisia M. , Obaldo Leonard G. , Dominy Warren G. , Behnke Keith C. 
Published: April 2007

AbstractWheat is used in shrimp feed as protein and energy sources, as well as a nutritive binder that promotes water stability. However, wheat may be contaminated with deoxynivalenol (DON or vomitoxin) when wet weather conditions prevail during the growing season. Deoxynivalenol‐contaminated wheat was added to shrimp diet to obtain DON levels of 0.2, 0.5, and 1.0 ppm. Pelleted diets were fed 3 times daily until satiation to Pacific white shrimp Liropenaeus vanna‐mei. Biological performance (live weight, weekly growth increment, feed conversion ratio, and survival) was determined biweekly for 16 wk. Histological characteristics of shrimp were determined on samples obtained after 8 and 16 wk of growth. The DON levels in ground wheat, feed mash, pellets, and freeze‐dried shrimp were determined using thin layer and high performance liquid chromatography. Deoxynivalenol levels of 0.2, 0.5, and 1.0 ppm in the diet significantly reduced shrimp body weight and/or growth rate. However, the effects of 0.2 and 0.5 ppm DON were manifested at later stages of shrimp growth, and 0.2 ppm DON significantly affected only growth rate and not body weight (P > 0.05). Feed conversion ratio and survival of shrimp fed diets containing 0.2, 0.5, and 1.0 ppm DON were not significantly different from those of shrimp fed the control diet (0.0 ppm DON). After 16 wk of growth, no DON was detected in freeze‐dried shrimp, and no consistent difference was observed in the histological organ profiles of shrimp fed diets containing various levels of DON. Because low levels of DON in the diet can significantly reduce body weight and growth rate of shrimp, feed ingredients should be monitored for DON.