bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth and Lipid Composition of Winter Flounder Juveniles Reared under Natural and Fixed Photoperiod and Temperature Conditions
Authors: Fraboulet E , Lambert Y , Tremblay R , Audet C 
Published: August 2012

Abstract
In age-0 winter flounder Pseudopleuronectes americanus, a fixed long photoperiod (14.5 h light: 9.5 h dark) applied during the first 45 d postsettlement did not improve growth compared with fish held under natural photoperiod conditions. After being reared under these two regimes until 29 October, juveniles exposed to the long photoperiod after settlement were maintained under the same conditions during the winter, but temperature was not allowed to decrease below 4°C. Juveniles previously exposed to the natural photoperiod were maintained under one of the following conditions: (1) natural photoperiod and natural temperature (1–9°C), (2) natural photoperiod and a minimum winter temperature of 4°C, or (3) long photoperiod and a minimum temperature of 4°C. Most mortality (80%) occurred within the first 2 months of the experiment. Juveniles that experienced the transition from natural to long photoperiod conditions displayed higher growth through the winter than did juveniles exposed to natural conditions; at the end of winter, fish that were transitioned to the long photoperiod were 25% longer (19 mm), were twice as heavy (125 mg), and contained twice as much total lipids (803 μg/mg) and five times more triacylglycerols (24% of total lipids) than juveniles subjected to the natural photoperiod. These results indicate that we may be able to eliminate the winter fasting that occurs under natural conditions and to elicit winter growth in this species by using photoperiod manipulation. In addition, it appears that a decrease in photoperiod is needed for fish to respond to a subsequent increase in photoperiod.
Received November 3, 2009; accepted May 27, 2010
Performance of Larval Florida Pompano Fed Nauplii of the Calanoid Copepod Pseudodiaptomus pelagicus
Authors: Cassiano Eric J , Ohs Cortney L , Weirich Charles R , Breen Nancy E , Rhyne Andrew L 
Published: August 2012

Abstract
The Florida pompano Trachinotus carolinus is a highly prized marine fish species, the larviculture of which currently includes the feeding of live rotifers and nauplii of brine shrimp Artemia spp. However, no previous studies have evaluated the feeding of copepod nauplii. In this study, the growth and survival of Florida pompano larvae fed nauplii of the calanoid copepod Pseudodiaptomus pelagicus were compared with those of larvae fed the standard reference diet of enriched rotifers Brachionus plicatilis. Experiments were conducted during the first 7–9 d posthatch (DPH), a period preceding the provision of Artemia nauplii. Treatments included feeding only copepod nauplii during the first day, the first three days, and on all days, as well as copepod nauplii mixed with rotifers during the entire experiment. In addition, the dietary effects on larval fatty acid composition were examined. Feeding copepod nauplii at a density of 2.0–3.5 nauplii/mL during the first day or the first three days of feeding had advantages over feeding only rotifers. However, after approximately 3 DPH, increased quantities of nauplii were needed to provide sufficient nutrients for growth. This was demonstrated in larvae fed copepod nauplii for the entire trial, for which survival was significantly higher than for the other treatments but for which growth was significantly reduced. Larvae fed a mixture of rotifers and nauplii for the entire trial had survival similar to that of larvae fed only rotifers (∼40%); however, growth was greater in larvae fed the mixed diet, suggesting that there is a nutritional advantage to including copepods in the diet. Fatty acid analyses revealed that increased levels of docosahexaenoic acid were associated with larvae fed copepods, which probably contributed to the observed higher survival and growth. These results indicate that there are multiple benefits to feeding copepods to Florida pompano larvae.
Received June 6, 2010; accepted August 10, 2010
Production Performance and Stress Tolerance of Sunshine Bass Raised on Reduced Fish Meal Feeds Containing Ethanol Yeast
Authors: Gause Brian , Trushenski Jesse 
Published: August 2012

Abstract
Ethanol yeast (EY) has been shown to be an effective alternative to fish meal (FM) in diets of sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis). Diets containing blends of FM and EY yield production performance similar or superior to that of diets containing no EY. Complete replacement of FM with EY, however, reduces feed palatability, impairs production performance, and may affect other aspects of livestock vigor. Accordingly, the objectives of this study were to determine the effects of dietary EY inclusion (with or without a palatant) on the feed intake, growth performance, and physiological robustness of sunshine bass after stressor exposure. Formulations were developed containing 15, 7.5, and 0% FM with EY as the primary alternative protein source. Experimental diets were prepared according to these formulations with and without the addition of 1% soluble canola protein concentrate as a palatant. Replicate tanks of juvenile sunshine bass (∼4.4 g) were fed the experimental feeds twice daily to apparent satiation for 9 weeks. Production performance was assessed, and then the fish were subjected to a 2-min net-chasing stress challenge protocol. Tissue samples were collected to allow for the determination of organosomatic indices and pre- and postchallenge hematology. Complete replacement of FM with EY resulted in reduced growth performance and efficiency and significantly altered whole-body proximate composition, reducing carcass protein and increasing carcass lipid. Palatant inclusion had no effect on diet acceptance or production performance. Plasma glucose and lysozyme activity were significantly affected by stress; however, dietary treatment did not affect these parameters. While cortisol levels were marginally higher among stressed fish, they were higher than expected in unstressed fish. Our results confirm previous research suggesting that the optimal level of FM in EY-based sunshine bass feed is between 7.5% and 15%. Further research is needed to fully understand the utilization of these feeds and their effects on the physiological status of sunshine bass.
Received July 13, 2010; accepted October 1, 2010
Precision of Striped Bass Fry Density Estimates
Authors: Matlock Gary C 
Published: August 2012

Abstract
Many fisheries for striped bass Morone saxatilis in the United States are supported by stocking hatchery-reared fish. Fingerlings are usually obtained by spawning adults in captivity, collecting fry in large (25–100-L) collection containers (vats), moving them to rearing facilities (e.g., earthen ponds and raceways), and subsequently harvesting the fish that remain after some predetermined period. The number of fry stocked is estimated, and the accuracy and precision are seldom known or reported. The effect of treating fry stocking estimates as “error free, complete counts” on survival and production estimates is, therefore, also unknown. The objective of this study was to document and determine the statistical precision of the procedures used at Texas Parks and Wildlife Department's Dundee Fish Hatchery through the 1990s (standard procedures still in use at many hatcheries) for estimating fry densities in vats. The precision of fry density estimates was directly correlated with the mean density and sample volume. Such estimates could be improved by reducing the water volume (especially when densities are low) in vats and using a standard sample volume (at least 15 mL) instead of adjusting the sample volume based on visual inspection of fry in vats. The number of samples could be reduced from 10 to 8 without substantially affecting precision. Further, the practice of removing the highest and lowest sample values should be discontinued. The resulting precision of subsequent fingerling survival and production statistics could benefit from these changes without a substantial increase in data analysis.
Received August 5, 2010; accepted October 4, 2010
Altered Growth Rates, Carcass Fatty Acid Concentrations, and Tissue Histology in First-Feeding Steelhead Fed a Fish-Meal- and Fish-Oil-Free Diet
Authors: Twibell Ronald G , Gannam Ann L , Ostrand Susan L , Holmes John S A , Poole Jeff B 
Published: August 2012

Abstract
A 12-week feeding trial was conducted to evaluate a fish-meal-free, fish-oil-free diet for use with first-feeding steelhead Oncorhynchus mykiss. The marine-based control diet (marine diet) contained sardine (Sardinops spp.) meal and pollock (Pollachius virens) liver oil as the primary sources of protein and lipid, respectively. The experimental diet (terrestrial diet) contained only terrestrial sources of protein (poultry by-product meal, blood meal, canola, corn gluten, and wheat gluten) and lipid (canola oil and flaxseed oil). Each diet was administered to five replicate groups of first-feeding fry. At the conclusion of the feeding trial, fish that were fed the marine diet exhibited significantly higher weight gain and feed efficiency than fish that were given the terrestrial diet. Survival was not significantly affected by dietary treatment. However, fish that received the terrestrial diet exhibited significantly lower hemoglobin concentration and percent packed cell volume. Histological examination indicated that in comparison with control fish, steelhead that were fed the terrestrial diet exhibited a lesser degree of vacuolation in hepatocytes, mild hypertrophy and hyperplasia of the nephron tubular epithelium, and intracellular vacuolation in epithelium of the pyloric caeca. Carcass crude protein concentration was significantly higher in fish that were fed the marine diet than in fish that were fed the terrestrial diet. After 2 weeks of feeding, steelhead that received the marine diet exhibited significantly higher carcass concentrations of 14:0, 16:0, 16:1, 20:1, 20:5(n-3), 22:5(n-3), and 22:6(n-3) fatty acids but significantly lower carcass concentrations of 18:1, 18:2(n-6), 18:3(n-6), 18:3(n-3), and 20:4(n-6) relative to fish that were given the terrestrial diet. These differences in carcass fatty acid concentrations persisted throughout the feeding trial. Results of this study indicate that the current terrestrial-based diet is not a satisfactory replacement for the standard marine-based diet used with first-feeding steelhead.
Received January 21, 2010; accepted January 22, 2011
Growth Performance and Tissue Fatty Acid Composition of Rainbow Trout Reared on Feeds Containing Fish Oil or Equal Blends of Fish Oil and Traditional or Novel Alternative Lipids
Authors: Trushenski Jesse T , Blaufuss Patrick , Mulligan Bonnie , Laporte Jérôme 
Published: August 2012

Abstract
Fish oil (FO) sparing is common in aquafeed formulation; however, some alternative lipids have proven to be more successful than others in ensuring adequate growth and maintenance of desirable fillet fatty acid (FA) composition. Depending on the lipids used, grow-out feeds influence the FA composition of the tissues of “lean-fleshed” fishes and their responsiveness to subsequent tailoring during finishing. To address whether different lipid sources similarly influence growth performance and tissue composition of a “fat-fleshed” fish, rainbow trout Oncorhynchus mykiss were reared on feeds containing FO or a 50:50 blend of FO and coconut oil (COCONUT), palm oil (PALM), standard soybean oil (STD-SBO), hydrogenated soybean oil (HYD-SBO), low-18:3(n-3) (alpha-linolenic acid) soybean oil (LO-ALA-SBO), or low-18:3(n-3) canola oil (LO-ALA-CAN). Two saturated FA (SFA)-enriched lipids derived from the processing of cottonseed (SFA-COT) or soybean (SFA-SBO) were also evaluated as 50% FO substitutes. After 7 weeks, growth performance was largely unaffected by dietary lipid source. Fillet levels of long-chain (LC) polyunsaturated FAs (PUFAs) among fish that received the HYD-SBO, LO-ALA-SBO, SFA-SBO, and SFA-COT feeds were equivalent to levels in fish that received the FO feed, despite an approximate 50% reduction in dietary LC-PUFA intake. Our results indicate that feeds containing a blend of FO and novel soy- or cottonseed-derived lipids yielded equivalent growth performance and fillet LC-PUFA content in rainbow trout. The use of STD-SBO, COCONUT, PALM, or LO-ALA-CAN did not impair growth or efficiency but did alter the fillet FA profile. Rainbow trout appeared to differ somewhat from other fishes in terms of dietary influence on tissue FA profile; however, the pattern of greater LC-PUFA retention in fish reared on SFA-rich feeds appears to be largely consistent among the fish taxa we have assessed.
Received January 19, 2010; accepted July 25, 2010
Effects of Dietary Distillers Dried Grains with Solubles and Soybean Meal on Extruded Pellet Characteristics and Growth Responses of Juvenile Yellow Perch
Authors: Schaeffer Travis W , Brown Michael L , Rosentrater Kurt A 
Published: August 2012

Abstract
A 126-d feeding trial was performed to investigate graded combinations of distillers dried grains with solubles (DDGS) and soybean meal (SBM) in diets formulated for yellow perch Perca flavescens. Six experimental diets contained DDGS and SBM at 0 and 31.5% (dry matter basis), respectively (0/31.5 diet), 10 and 26% (10/26), 20 and 20.5% (20/20.5), 30 and 15% (30/15), 40 and 9.5% (40/9.5), and 50 and 4% (50/4) to obtain similar levels of crude protein (mean ± SE = 30.1 ± 0.2%), crude lipid (16.7 ± 0.7%), and digestible energy (13.5 ± 0.2 kJ/g). Fourteen fish (initial individual weight = 19.1 ± 0.5 g) were randomly selected and stocked into each of twenty-four 110-L tanks (4 replicate tanks/diet). Common biological and mechanical filter systems were used to recirculate the water and maintain similar water quality. Fish that received the 40/9.5 diet exhibited the highest apparent absolute weight gain and percent weight gain, while fish that were fed the 10/26, 20/20.5, 30/15, and 40/9.5 diets exhibited similar absolute weight gain. Fish that were given the 20/20.5, 30/15, and 40/9.5 diets also exhibited similar percent weight gain. Fulton's condition factor and apparent protein digestibility were significantly lower and higher, respectively, for fish that received the 50/4 diet than for all other treatment groups. Crude protein and crude lipid levels in muscle samples did not significantly differ among treatment groups. Results indicated that yellow perch can utilize DDGS plus SBM at a combined inclusion level of up to 49.5% without negative effects on growth. The mechanical strength and color of the extruded pellets were related to the level of DDGS plus SBM in the feed blends. Hepatosomatic indices were correlated with pellet color, while protein digestibility decreased with increasing pellet strength.
Sexual Maturation and Milt Quality of the San Pedro Mártir Trout Using an Artificial Photoperiod
Authors: Aguilar-Juárez Marisela , Ruiz-Campos Gorgonio , Paniagua-Chávez Carmen G 
Published: August 2012

Abstract
The sexual maturation and milt quality of the San Pedro Mártir trout Oncorhynchus mykiss nelsoni (SPMT) were studied in captivity using an artificial photoperiod and a recirculating system that kept the water quality within the range recorded in the natural habitat of this subspecies. During the 21.8 months of the study, male SPMT reached the highest weight (379 ± 48 g [mean ± SD]) and total length (344 ± 19 mm) recorded for this type of trout. Male maturation was induced at 7.5 months. Eight ripe males (200–320 mm total length) were stripped by abdominal pressure to obtain milt on six occasions from January to April 2009, at intervals ranging from 2 to 4 weeks. Spermatozoa motility varied from 80% to 95%, with a maximum duration of 50–55 s. Milt volume ranged from 165 to 228 μL per organism, and spermatozoa concentration ranged from 235 × 106 to 4,772 × 106 cells/mL. The mean spermatozoa flagellum length was 33.17 μm, and head width and length were 2.14 and 2.72 μm, respectively. This work demonstrates that San Pedro Mártir trout can be maintained and induced to mature sexually in a recirculating system using artificial photoperiod and temperature control. This information can be useful in management and conservation programs for this endemic trout in Mexico.
Use of Fish Hydrolysates and Fish Meal Byproducts of the Alaskan Fishing Industry in Diets for Pacific White Shrimp Litopenaeus vannamei
Authors: Forster Ian P , Bechtel Peter , Dominy Warren G , Lane Sandro , Avena Roberto , Ju Zhi Yong , Conquest Lytha 
Published: August 2012

Abstract
We determined the suitability of four fish hydrolysates and two fish meals (Pacific halibut Hippoglossus stenolepus and arrowtooth flounder Atheresthes stomias; all derived from byproducts of the Alaskan fishing industry) as replacements for menhaden fish meal in shrimp diets. A control diet (30% crude protein; 8.5% crude lipid) was produced with menhaden meal (13% of diet). Experimental diets were manufactured by using each hydrolysate or fish meal to replace 50% of the menhaden meal on an isonitrogenous basis. Each diet was fed to Pacific white shrimp Litopenaeus vannamei in an outdoor, zero-water-exchange system for 8 weeks. Final weight, survival, feed efficiency, and growth rate were compared among treatments by analysis of variance. The final weights and growth of Pacific white shrimp fed two of the hydrolysates (one acidified to pH 3.8 and left in a liquid state; the other acidified, then neutralized to pH 6.5 and drum-dried) and the two fish meals were not different from those of shrimp fed the control diet. Shrimp that were given the other two hydrolysates (one acidified to pH 3.8 and then drum-dried; the other hydrolyzed [but not acidified] and then drum-dried) had lower final weights and growth than shrimp fed the control diet. These data indicate that the two fish meals and two of the hydrolysates in this trial can replace 50% of menhaden meal in diets for shrimp, although there is some loss of growth potential in some cases. The lack of a diet effect on feed efficiency indicates that the growth differences were mostly the result of differences in feed intake rather than nutritional quality.
Efficacy of a Commercial Probiotic Relative to Oxytetracycline as Gram-Negative Bacterial Control Agents in a Rotifer (Brachionus plicatilis) Batch Culture
Authors: Rotman Federico J , Riche Marty , Van Wyk Peter , Benetti Daniel D 
Published: August 2012

Abstract
Two trials were conducted to evaluate two gram-negative bacterial control strategies in batch cultures of the rotifer Brachionus plicatilis. In the first trial, rotifers at an initial density of 47/mL were cultured for 5 d and dosed with a 10-mg/L solution of either oxytetracycline or a commercial probiotic consisting principally of Bacillus and Lactobacillus. In the second trial, rotifers at an initial density of 140/mL were cultured for 4 d and dosed with 20-mg/L solutions of oxytetracycline or the probiotic. Rotifer density, egg counts, and egg : female ratios were determined daily. At the termination of trial 1 and on days 0, 2, and 4 of trial 2, counts of bacterial colonies were conducted to estimate bacterial loads in the rotifer culture water. Oxytetracycline was an effective antimicrobial and enhanced rotifer production in the higher-density culture but had only a marginal effect on production in the lower-density culture. Conversely, inoculation of the low-density culture with the probiotic had no effect on rotifer production. Inoculation of the high-density culture adversely affected rotifer production by increasing mortality and reproductive inhibition.
Oxygen Consumption of the Prawn Macrobrachium americanum over the Temperature Range of its Native Environment and in Relation to its Weight
Authors: García-Guerrero Marcelo , Orduña-Rojas Javier , Cortés-Jacinto Edilmar 
Published: August 2012

Abstract
Cauque prawns Macrobrachium americanum of four different weights were tested at different temperatures to determine the differences in their oxygen consumption. The prawns were studied in a closed respirometer system in individual assays of 30 min each. Temperature (18–30°C) had a noticeable effect on oxygen consumption for all weights of prawns; weight had a less significant effect. In all cases, the mass-specific oxygen consumption rate of small prawns was higher than that of large prawns for all of the temperatures studied.
Relationship between Chlorhexidine Gluconate Skin Concentration and Microbial Density on the Skin of Critically Ill Patients Bathed Daily with Chlorhexidine Gluconate
Authors: Popovich Kyle J. , Lyles Rosie , Hayes Robert , Hota Bala , Trick William , Weinstein Robert A. , Hayden Mary K. 
Published: August 2012

Objective and Design.Previous work has shown that daily skin cleansing with Chlorhexidine gluconate (CHG) is effective in preventing infection in the medical intensive care unit (MICU). A colorimetric, semiquantitative indicator was used to measure CHG concentration on skin (neck, antecubital fossae, and inguinal areas) of patients bathed daily with CHG during their MICU stay and after discharge from the MICU, when CHG bathing stopped.Patients and Setting.MICU patients at Rush University Medical Center.Methods.CHG concentration on skin was measured and skin sites were cultured quantitatively. The relationship between CHG concentration and microbial density on skin was explored in a mixed-effects model using gram-positive colony-forming unit (CFU) counts.Results.For 20 MICU patients studied (240 measurements), the lowest CHG concentrations (0–18.75 μg/mL) and the highest gram-positive CFU counts were on the neck (median, 1.07 log10CFUs;P= .014). CHG concentration increased postbath and decreased over 24 hours (P< .001). In parallel, median log10CFUs decreased pre- to postbath (0.78 to 0) and then increased over 24 hours to the baseline of 0.78 (P= .001). A CHG concentration above 18.75 μg/mL was associated with decreased gram-positive CFUs (P= .004). In all but 2 instances, CHG was detected on patient skin during the entire interbath (approximately 24-hour) period (18 [90%] of 20 patients). In 11 patients studied after MICU discharge (80 measurements), CHG skin concentrations fell below effective levels after 1–3 days.Conclusion.In MICU patients bathed daily with CHG, CHG concentration was inversely associated with microbial density on skin; residual antimicrobial activity on skin persisted up to 24 hours. Determination of CHG concentration on the skin of patients may be useful in monitoring the adequacy of skin cleansing by healthcare workers.