bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationships among Feed Intake, Feed Efficiency, and Growth in Juvenile Rainbow Trout
Authors: Silverstein Jeffrey T 
Published: March 2006

Abstract
Improving the efficiency of aquaculture production is important for both economic and environmental sustainability. The purpose of this work was to define the relationships between feed intake, weight gain, and feed efficiency (measured as residual feed intake) in rainbow trout Oncorhynchus mykiss fed either to apparent satiation or a limited ration. The results indicated that under an apparent satiation feeding regime, a weak but significant correlation existed between weight gain and residual feed intake (RFI; r = −0.31, P &lt; 0.04). When fed a limited ration, the correlation between weight gain and RFI was stronger (r = −0.57, P &lt; 0.001). Genetic differences between family groups were detected only under the apparent satiation feeding regime and not under limited feeding. Although these experiments were conducted on different groups of fish, it appears that the variation in RFI was greater in satiation-fed fish than in fish fed a limited ration (coefficient of variation = 174% versus 33%). Estimates of residual feed intake measured on individuals from full-sib families and on groups of individuals from the same families were correlated (r = 0.66, P = 0.03), suggesting that the feed efficiency measured on individually reared fish captures a trait expressed in social groups as well.
Binding Affinities of Hepatic Nuclear Estrogen Receptors for Genistein in Channel Catfish
Authors: Kelly Anita M , Green Christopher C 
Published: March 2006

Abstract
Soybean meal, the major protein source used in commercial feeds for channel catfish Ictalurus punctatus, contains natural phytoestrogens known as isoflavones, many of which have been found to be endocrine disruptors. This study investigated whether genistein (an isoflavone) in a soybean-based diet would increase plasma vitellogenin (Vtg) concentrations and whether it would compete with estradiol (E2) for binding sites on adult channel catfish hepatic estrogen receptors (ERs). Three-year-old channel catfish males and females were fed a casein-based diet (control) or a soybean-based diet. The genistein concentrations were 93.2 ng/g and 415,800 ng/g in the control and soybean diets, respectively. The binding specificity of the ERs was assessed by binding-affinity studies. In order of decreasing binding affinity, ethinylestradiol &gt; E2 &gt; genistein &gt; testosterone, demonstrating that the hepatic ERs in channel catfish bind estrogens and genistein more than androgens. No significant differences in affinity (Kd) were observed for hepatic ERs in male or female catfish fed the soybean diet compared with those fed the control diet. Significant increases in binding capacity (B max) for males fed the soybean diet (158 ± 15 fmol/mg protein) were evident compared with males fed the control diet (73 ± 4 fmol/mg protein). Genistein competed with [3H]E2 for hepatic ERs in both the male and female channel catfish. The relative binding affinities in male ERs were higher (2.72) than those in female ERs (1.17) for genistein. Because diets of farm-raised channel catfish are routinely composed of high quantities of soybean meal, the findings that genistein stimulates Vtg production in male channel catfish and binds to the ERs in both male and female channel catfish suggest that dietary genistein could alter production traits. However, further research to elucidate the effects of genistein on catfish reproduction is necessary to determine the impact of this phytoestrogen on catfish physiology.
A Three-Dimensional Computational Fluid Dynamics (CFD) Model Analysis of Free Surface Hydrodynamics and Fish Passage Energetics in a Vertical-Slot Fishway
Authors: Khan Liaqat A. 
Published: March 2006

Abstract
A three-dimensional (3-D), computational fluid dynamics model of a vertical-slot fishway was used to characterize fishway hydrodynamics. The computational grid of a seven-pool fishway, consisting of about half a million hexahedral and prism cells, simulates the spatial variations of water surface and velocity in the model domain. Model results indicate a strong 3-D velocity field in the fishway, with eddies, flow separations, vortices, upwellings, and downwellings. Velocities and drag forces encountered by upstream migrating fish and energy expenditures in ascending the fishway are determined from the fishway hydrodynamics. The computed results are consistent with published information. Based on burst swimming speeds, the species of salmon Oncorhynchus spp. capable of migrating through the fishway were identified. Because the upriver spawning migration of adult salmon is energetically expensive, a quantification of energy expenditure in the fishways could be utilized for optimizing the design, operation, and management of fishways. Though this paper presents a model of a vertical-slot fishway, the modeling approach is applicable to other types of fishways.
Electrical Conductivity as Applied to Electrofishing
Authors: Kolz A. Lawrence 
Published: March 2006

AbstractThe electrical power transferred from water to fish when electrofishing is related to the ratio between the electrical conductivity of the water and that of the fish. Measuring the conductivity of water is easily accomplished with a standard conductivity meter, but determining it for fish has been difficult. No other industry standard or biological methodology apparently requires knowledge of the electrical conductivity of an object or fish freely suspended in an electrified volume of water. Therefore, the technology associated with electrofishing is confronted with the dilemma of explaining the seemingly incompatible differences between the static, electrical conductivities measured for immobilized fish and the dynamic, effective conductivities observed with live fish. To resolve this conflict, a new parameter, immersion conductivity, is introduced, accompanied by a proposed technique to measure this parameter for fish or other conductive materials in electrified volumes of water. Electrical principles based on the maximum power theorem are applied to develop relationships between the size of the distorted electrical field surrounding an immersed material and the resultant values of immersion conductivity. The immersion conductivity for fish is demonstrated to be a function of the cross‐sectional area of the water volume relative to that of the fish contained therein; it is not a fixed value. Initially, inwater voltage gradient measurements are recorded for a rubber cylinder of known electrical conductivity to demonstrate the feasibility of the test protocol and produce appropriate power graphs. Immersion conductivity values of 72–204 μS/cm were then measured for sacrificed fish, and this range correlates with effective conductivity values previously reported for live fish. The protocol associated with the measurement of immersion conductivity determines the optimal water conductivity for maximum power transfer, thereby creating research opportunities for comparing the in vivo thresholds of electroshock response among different species of fish or different‐sized fish of the same species.
Evaluation of Alveolar Bone Support of the Permanent Canine in Cleft and Noncleft Patients
Authors: Boyarskiy Simon , Choi Hyung Jun , Park Kitae 
Published: March 2006

Objective: To quantitatively compare the alveolar bone support ratio of the permanent canine in cleft patients who received secondary alveolar bone graft with that of the population without clefts. Design: Retrospective study utilizing periapical radiographs of the subjects with and without clefts. Setting: Hospital and university based. Patients: Eighteen unilateral and 9 bilateral cleft patients who had secondary bone graft procedures. Main Outcome Measures: Alveolar bone support of the permanent canine utilizing the ratio of bone height to root length. Results: Average bone support for the permanent canine was 88.55% in patients with clefts and 95.59% in patients with no history of clefts. This difference was statistically significant. There was no statistically significant difference in alveolar bone support ratio between the unilateral and bilateral cleft patients. Conclusions: Although alveolar bone support was significantly higher in the noncleft control group, a successful level of alveolar bone support was achieved for the permanent canine on the cleft site after secondary bone graft. There was no difference in alveolar bone support achieved for the permanent canine whether the type of the cleft was unilateral or bilateral.
Bilateral Macrostomia as an Isolated Pathology
Authors: Gleizal Arnaud , Wan Derrick C. , Picard Arnaud , Lavis Jean-François , Vazquez Marie-Paule , Beziat Jean-Luc 
Published: March 2006

Objective: Congenital macrostomia is a lateral orofacial cleft between the maxillary and mandibular components of the first branchial arch. Bilateral macrostomia is a poorly characterized malformation, with only 14 cases reported in the literature. The purpose of this study was to compare our experience with the world literature. Method: A retrospective analysis of 20 cases of bilateral congenital macrostomia was conducted; 6 cases were drawn from 2 maxillofacial surgery units and 14 cases from the world literature. Cases of bilateral congenital macrostomia were compared with cases of unilateral forms using a review of the literature post-1954. Among the six cases identified from the two maxillofacial surgery units, three were treated with linear sutures and three with Z-plasty. Subsequent aesthetic and functional results were analyzed. Results: Compared to unilateral forms, bilateral macrostomia is more often isolated without ear or skin deformities. Moreover, there are a greater proportion of larger defects among cases with bilateral macrostomia when compared to unilateral macrostomia. Alimentation, phonation, and mouth opening were always normal. The two sides were always symmetric. Only one case presented with the complication of skin contractions during lip movement. Conclusion: The etiopathogenesis of bilateral macrostomia is unclear. Although over 50% of the reported cases of bilateral macrostomia are isolated, this condition presents a therapeutic challenge. In the case of bilateral forms, the surgeon must define the commissure position without a normal side. Repair thus requires extraoral landmarks and normal measurements.
Tessier 3 Cleft with Clinical Anophthalmia: Two Case Reports and a Review of the Literature
Authors: Wenbin Zhang , Hanjiang Wu , Xiaoli Chen , Zhonglin Li 
Published: March 2006

Objective: Tessier 3 cleft with clinical anophthalmia is one of the rarest craniofacial clefts, and hence little has been published about its management and treatment. This article presents two cases of Tessier 3 cleft with clinical anophthalmia. A review of the literature helps to diagnose these complex facial deformities. The treatment and etiopathogenesis are discussed.
Contribution of ammonium ions to the lethality and antimetamorphic effects of ammonium perchlorate
Authors: Goleman Wanda L. , Carr James A. 
Published: March 2006

AbstractAmmonium perchlorate (AP) is a widespread military waste product in the United States and is a potent thyroid function disruptor in all vertebrates tested thus far. To determine the relative contribution of ammonium ions to the toxicity of AP, we exposed embryonic and larval Xenopus laevis to various concentrations of sodium perchlorate (SP) or ammonium chloride (AC). Ammonium perchlorate was significantly more lethal than SP; 5-d LC50s were 83 and 2,780 mg/L, respectively. To determine whether ammonium ions contribute to the antithyroid effects of AP, we exposed embryonic and larval X. laevis to two sublethal, environmentally relevant concentrations of AP or identical concentrations of AC or SP. At the smaller concentration, only AP delayed metamorphosis and reduced hindlimb growth. Sodium perchlorate and AP, but not AC, prevented metamorphosis and reduced hindlimb growth at the greater concentration. Although AP was slightly more effective in reducing outward manifestations of thyroid disruption, both perchlorate salts, unlike AC, caused profound histopathologic changes in the thyroid. Exposure to the higher concentration of either perchlorate salt produced a feminizing effect, resulting in a skewed sex ratio. We conclude that ammonium ions contribute significantly to the toxicity of AP but not to the direct antithyroid effects of perchlorate.
Biochemical and histopathological effects in pearl dace (Margariscus margarita) chronically exposed to a synthetic estrogen in a whole lake experiment
Authors: Palace Vince P. , Wautier Kerry G. , Evans Robert E. , Blanchfield Paul J. , Mills Kenneth H. , Chalanchuk Sandra M. , Godard Danielle , McMaster Mark E. , Tetreault Gerald R. , Peters Lisa E. , Vandenbyllaardt Lenore , Kidd Karen A. 
Published: March 2006

AbstractPotential effects of exposure to the synthetic estrogen 17α-ethynylestradiol (EE2) were examined in several species of fish from a lake experimentally treated with environmentally relevant concentrations of the contaminant. Ethynylestradiol was added to Lake 260, a small Precambrian shield lake at the Experimental Lakes Area in northwestern Ontario, Canada, from May to October of 2001, 2002, and 2003. Mean concentrations of EE2 in epilimnetic waters ranged between 4.5 and 8.1 ng/L during the three years, with overall means of 6.1 (±2.8), 5.0 (±1.8), and 4.8 (±1.0) ng/L for the three years, respectively. Male and female pearl dace (Margariscus margarita) captured after EE2 additions began contained up to 4,000-fold higher concentrations of the egg yolk precursor vitellogenin than fish captured from the same lake before the EE2 additions or when compared to fish from reference lakes. Edema in the ovaries, inhibited development of testicular tissue, intersex, and histopathological kidney lesions were all evident in fish exposed to EE2. Some indications that EE2 exposure affected in vitro steroidogenic capacity of the ovaries and the testes existed, although results were not always consistent between years. Pearl dace abundance was similar in the lake treated with EE2 and the reference lake. A trend exists toward a reduced overall population of pearl dace from the treated and reference lakes, as do indications that young-of-the-year size classes are less abundant in the EE2-treated lake. Biochemical and histopathological impacts observed in fish exposed to EE2 in this study have not yet been linked to clear population level impacts in pearl dace. Monitoring of these populations is ongoing.
Reproductive effects of the endocrine disruptor fenarimol on a Baltic amphipod Monoporeia affinis
Authors: Jacobson Therese , Sundelin Brita 
Published: March 2006

Abstract
An endocrine disruptor, the fungicide fenarimol, was investigated regarding its effects on reproduction and hormone (ecdysteroid) levels in the deposit-feeding amphipod Monoporeia affinis. In addition, the influence of food shortage, both by itself and in combination with fenarimol, on reproduction was examined. Field-collected amphipods were exposed in flow-through microcosms during the period of sexual maturation and mating in four treatment series: Control with low food, fenarimol with low food, control with high food, and fenarimol with high food. Fenarimol was added at a concentration of 0.3 mg/L in two pulses/week. Results show that fenarimol has a negative effect on fertilization rate and male mating ability. Results were supported by a tendency toward delayed male sexual development. Food shortage decreased weight in both sexes and retarded female oocyte development. Higher ecdysteroid levels were recorded in males than in females, and food shortage increased male ecdysteroid levels. No effect of fenarimol exposure on ecdysteroid levels was observed. No synergistic effects of fenarimol and food shortage could be distinguished in any variable examined. Thus, M. affinis was vulnerable to reproductive impairment by fenarimol, with effects on the next generation (i.e., a disturbed sexual development and fertilization ability). Food shortage has negative effects on M. affinis, but it does not enhance the effects of fenarimol.
Elevated fluctuating asymmetry in eastern mosquitofish (Gambusia holbrooki) from a river receiving paper mill effluent
Authors: Estes Eleanor C. J. , Katholi Charles R. , Angus Robert A. 
Published: March 2006

AbstractThe present study investigated whether fluctuating asymmetry can serve as a useful biomarker of environmental stress in the eastern mosquitofish (Gambusia holbrooki). Fluctuating asymmetry was measured in sexually mature females sampled from two Florida, USA, coastal streams: The Fenholloway River, which is dominated by effluent from a paper mill, and Spring Creek, a tributary to the Fenholloway River (Taylor County, FL, USA) that does not receive paper mill effluent. Nine morphometric (lengths of the A and B scales, fifth pectoral fin ray, supraorbital canal, and preorbital canal and the sixth gill raker on the first brachial arch; orbit diameter; distance from the dorsal-ventral midpoint of the eye socket to the base of the pectoral fin; and distance from the postorbital canal to the operculum) and five meristic traits (numbers of scales in the lateral line, radii on the A and B scales, pectoral fin rays, and gill rakers on the first brachial arch) were included. For each of the three indexes of fluctuating asymmetry that were used, the majority of the traits showed a higher level of fluctuating asymmetry in fish from the Fenholloway River than in fish from Spring Creek. For two of the indexes, the difference was significant. Comparisons of mean values for fluctuating asymmetry (over all traits) for each fish and the means of a composite index of asymmetry both indicated that fish from the Fenholloway River had significantly greater overall fluctuating asymmetry than those from Spring Creek. Results of the present study are consistent with the hypothesis that environmental stress increased the level of fluctuating asymmetry in fish from the Fenholloway River. Thus, fluctuating asymmetry appears to be a useful biomarker for stress-induced developmental instability in the eastern mosquitofish.
Toxicity of weathered Exxon Valdez crude oil to pink salmon embryos
Authors: Brannon Ernest L. , Collins Keya M. , Brown John S. , Neff Jerry M. , Parker Keith R. , Stubblefield William A. 
Published: March 2006

Abstract
Research was conducted at the University of Idaho (Moscow, ID, USA) on the toxicity of weathered Exxon Valdez crude oil to embryos of pink salmon from 2001 to 2003 for the purpose of comparing these data with those from the National Oceanic and Atmospheric Administration Fisheries Laboratory at Auke Bay (AK, USA). Mortality reported at Auke Bay for embryos chronically exposed to very low concentrations of aqueous solutions of weathered oil, measured as dissolved polycyclic aromatic hydrocarbons (PAHs), was inconsistent with that in other published research. Using the Auke Bay experimental design, we found that toxicity is not evident in pink salmon embryos until chronic exposure to laboratory weathered and naturally weathered oil concentrations exceeding 1,500 and 2,250 ppm, respectively, representing a total PAH tissue burden in excess of 7,100 ppb. Effluent hydrocarbons also drop well below concentrations sufficient to cause harm over the time frame of a few weeks, regardless of oiling level. Resolution of differences with Auke Bay involved the source of contributing hydrocarbons. The experimental design did not exclude dispersed oil droplets from the aqueous solution; thus, toxicity was not limited to the dissolved hydrocarbon fraction. The implications of the present results are discussed regarding the toxic risk of weathered oil to pink salmon embryos in streams of Prince William Sound (AK, USA).
Source apportionment modeling of volatile organic compounds in streams
Authors: Pankow James F. , Asher William E. , Zogorski John S. 
Published: March 2006

Abstract
It often is of interest to understand the relative importance of the different sources contributing to the concentration cw of a contaminant in a stream; the portions related to sources 1, 2, 3, etc. are denoted cw1, cw2, cw3, etc. Like cw, the fractions α1 = cw,1/cw, α2 = cw,2/cw, α3 = cw,3/cw, etc. depend on location and time. Volatile organic compounds (VOCs) can undergo absorption from the atmosphere into stream water or loss from stream water to the atmosphere, causing complexities affecting the source apportionment (SA) of VOCs in streams. Two SA rules are elaborated. Rule 1: VOC entering a stream across the air/water interface exclusively is assigned to the atmospheric portion of cw. Rule 2: VOC loss by volatilization, flow loss to groundwater, in-stream degradation, etc. is distributed over cw,1, cw,2, cw,3, etc. in proportion to their corresponding a values. How the two SA rules are applied, as well as the nature of the SA output for a given case, will depend on whether transport across the air/water interface is handled using the net flux F convention or using the individual fluxes J convention. Four hypothetical stream cases involving acetone, methyl-tert-butyl ether (MTBE), benzene, chloroform, and perchloroethylene (PCE) are considered. Acetone and MTBE are sufficiently water soluble from air for a domestic atmospheric source to be capable of yielding cw values approaching the common water quality guideline range of 1 to 10 μg/L. For most other VOCs, such levels cause net outgassing (F &gt; 0). When F &gt; 0 in a given section of stream, in the net flux convention, all of the αj for the compound remain unchanged over that section while cw decreases. A characteristic time τd can be calculated to predict when there will be differences between SA results obtained by the net flux convention versus the individual fluxes convention. Source apportionment modeling provides the framework necessary for comparing different strategies for mitigating contamination at points of interest along a stream.
An algal probe for copper speciation in marine waters: Laboratory method development
Authors: Karner Dawn A. , Shafer Martin M. , Overdier Joel T. , Hemming Jocelyn D. C. , Sonzogni William C. 
Published: March 2006

Abstract
Laboratory-based algal assays were developed to explore the bioavailability of copper to the marine alga Thalassiosira weissflogii. A calibration strategy was developed that avoided use of the synthetic ligand ethylenediaminetetraacetic acid (EDTA) in the Aquil growth medium, thereby allowing ambient metal speciation. In a comparison of T. weissflogii cells grown in Aquil medium with EDTA to medium containing no added copper, zinc, and less than 0.003 nM of EDTA, no significant growth differences were observed after 8 d, indicating adequate stored nutrients. A 30-h assay was selected as the optimal time frame after examination of data from concentration-response experiments. Using 65Cu stable isotope additions, parameters examined included growth, chlorophyll a, copper uptake, phytochelatin production, and dissolved organic carbon excretion. The T. weissflogii specific growth rates decreased from 1.36 d−1 at pCu (i.e., the negative logarithmic concentration of free Cu) = 8.8 to 0.56 d−1 at pCu = 7.8, whereas intercellular copper concentrations increased from 13.6 to 70.1 fg/cell, respectively. Calculated values of the copper concentration that caused a 50% reduction in algal growth of pCu = 7.7 and copper per algal mass of 625 μg/g were established. Using an algal assay based on EDTA-free culture medium, along with trace-metal clean techniques, the effect of copper on T. weissflogii and the speciation of copper in marine waters can be studied.