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Delbert M Gatlin - One of the best experts on this subject based on the ideXlab platform.
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evaluating the dietary taurine requirement of hybrid striped bass Morone Chrysops x m saxatilis
Aquaculture, 2021Co-Authors: Blaine Suehs, Delbert M GatlinAbstract:Abstract A dietary requirement for the sulfonic acid taurine has been documented in many marine species. However, it has not been well studied in hybrid fish with freshwater and marine genes, such as the hybrid striped bass (Morone Chrysops x M. saxatilis). Therefore, an 8-week feeding trial was conducted to evaluate the effects of various levels of dietary taurine on growth performance, health, and body composition of juvenile hybrid striped bass. Four diets were formulated from practical ingredients and supplemented with DL-methionine at 0.54% of dry weight to meet the hybrid striped bass' established total sulfur amino acid requirement of 1.0% of dry diet, and taurine was supplemented incrementally at 0, 0.5, 1, and 2% of dry weight. Two additional diets were prepared without DL-methionine supplementation to be marginally deficient in methionine (0.49% by weight) and either supplemented with or without taurine at 1% dry weight to evaluate the potential interactions between methionine and taurine. Diets containing increment levels of taurine were determined to show no significant (P > .05) differences in terms of weight gain, feed efficiency (FE), whole-body composition, hepatosomatic index (HSI), intraperitoneal fat ratio (IPF ratio), or muscle yield. However, hybrid striped bass fed the methionine-deficient diets had significantly (P
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relative use of dietary carbohydrate non essential amino acids and lipids for energy by hybrid striped bass Morone Chrysops m saxatilis
Aquaculture, 2015Co-Authors: Sergio Castillo, Misael Rosales, Alton F Burns, Maria R Mendoza, Delbert M GatlinAbstract:Abstract A comparative feeding trial was undertaken to evaluate the relative use of dietary carbohydrate, non-essential amino acids (NEAA), and lipids for energy by hybrid striped bass Morone Chrysops ♀ × M. saxatilis ♂. The control diet was formulated to contain 40% crude protein, 25% dextrinized corn starch as available carbohydrate (CHO) and 10% lipid. In the three experimental diets, the 25% dextrinized starch was replaced with either, 25% NEAA (12.5% l -glutamate and 12.5% l -aspartate), an additional 11% lipid (21% total lipid; designated high-lipid diet), or 0% CHO with protein and lipid components concentrated to 53.3% and 13.3%, respectively, and each diet was fed to juvenile fish such that all groups received equal amounts of intact protein. Juvenile hybrid striped bass (average initial weight of 21.1 g/fish) were stocked as groups of 12 fish in 110-L aquaria containing fresh water and operated as a recirculating system. Fish in triplicate aquaria were fed each dietary treatment at a rate approaching apparent satiation for 6 weeks. Fish fed the control diet with 25% CHO or high-lipid diet had significantly ( P
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the effects of prebiotics on the digestive enzymes and gut histomorphology of red drum sciaenops ocellatus and hybrid striped bass Morone Chrysops m saxatilis
British Journal of Nutrition, 2013Co-Authors: Maritza Anguiano, Camilo Pohlenz, Alejandro Buentello, Delbert M GatlinAbstract:The effects of four prebiotics (fructo-oligosaccharide, Bio-MOS®, transgalacto-oligosaccharide and GroBiotic®-A) on digestive enzymes and intestinal morphology were studied in juvenile hybrid striped bass (Morone Chrysops×M. saxatilis) and red drum (Sciaenops ocellatus) using two separate 8-week feeding trials. Red drum were fed experimental diets with the four prebiotics each individually supplemented at 1 % and hybrid striped bass were fed diets supplemented with GroBiotic®-A at 1 and 2 %. Both trials were conducted with each diet fed to apparent satiation twice per d to three replicate groups of fifteen juvenile fish. For histomorphological analysis, gastrointestinal tract (GIT) samples from three randomly selected fish per tank were taken at 4 and 8 weeks for hybrid striped bass and at 8 weeks for red drum. For both trials, GIT samples from two randomly selected fish per tank were taken at 4 and 8 weeks and analysed for pepsin, trypsin, chymotrypsin, aminopeptidase, α-amylase, lipase, and both acid and alkaline phosphatase activities. The results of the histological evaluation indicated that the inclusion of prebiotics was adequate to elicit structural changes in the GIT of both species. On the other hand, no significant changes in the enzyme activities were detected at week 8 in both species. However, there was a transient effect of Bio-MOS® supplementation on the activities of aminopeptidase, α-amylase and alkaline phosphatase at week 4 in red drum only. Thus, previously observed improvements in nutrient digestibility by these fish in response to prebiotic supplementation appear to be mostly related to changes in GIT structure as opposed to the enhancement of digestive enzyme activity.
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dietary supplementation of arginine and or glutamine influences growth performance immune responses and intestinal morphology of hybrid striped bass Morone Chrysops Morone saxatilis
Aquaculture, 2012Co-Authors: Zhenyan Cheng, Delbert M Gatlin, Alejandro BuentelloAbstract:Abstract Various studies with fish species indicate that dietary arginine (Arg) and glutamine (Gln) supplementation may support an enhanced performance beyond simply improving weight gain. Therefore, a feeding trial was conducted to determine the effects of dietary Arg or Gln on growth performance, immune responses and intestinal morphology of juvenile hybrid striped bass, Morone Chrysops × Morone saxatilis (4.1 ± 0.02 g, initial average weight). The basal diet was formulated from menhaden fishmeal and solvent-extracted soybean meal to contain 45% crude protein and 10% lipid. Arginine and Gln were singularly added to the basal diet at either 1% or 2% or both amino acids were added in combination at 1% to formulate experimental diets with adjustments in glycine to maintain all diets iso-nitrogenous. Fish were fed the experimental diets for a period of 8 weeks, at the end of which final weight, specific growth rate and feed efficiency were significantly ( P Arginine and/or Gln supplementation tended to improve neutrophil oxidative radical production, but not significantly ( P > 0.05). However, significantly higher serum lysozyme activity was observed in fish fed the diet supplemented with Arg at either 1 or 2% and Gln at 1%. Intracellular superoxide anion production by hybrid striped bass macrophages also tended to increase, while extracellular superoxide anion production was significantly improved by supplementation of Arg at 1% and Gln at either 1 or 2% of diet. Morphometric analyses demonstrated positive effects of both dietary Arg and Gln on histo-morphological measurements in different portions of the gastrointestinal tract of hybrid striped bass. The 1% Arg diet resulted in the greatest increases in size of the chosen enteric structures, but the other four experimental diets also significantly improved the scores for various intestinal portions compared to fish fed the basal diet. Results from the present experiment demonstrate the importance of dietary supplementation of both Arg and Gln in improving growth performance, eliciting positive changes to several components of the innate immune system, and also benefiting the intestinal functionality of hybrid striped bass.
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hepatic glucose utilization and lipogenesis of hybrid striped bass Morone Chrysops Morone saxatilis in response to dietary carbohydrate level and complexity
Aquaculture Nutrition, 2008Co-Authors: Steven D Rawles, S B Smith, Delbert M GatlinAbstract:The influence of carbohydrate level and complexity on in vitro hepatic glucose utilization and lipogenesis were determined in hybrid striped bass, Morone Chrysops [female symbol] x Morone saxatilis [male symbol]. Six isocaloric, isonitrogenous diets containing glucose, maltose, or dextrin at two different levels (200 or 400 g kg⁻¹ diet) were fed to adult fish for 15 weeks. Liver explants were obtained at near-maximum postprandial glycaemic response and incubated with radioactive labelled substrates. Glycogen synthesis from [¹⁴C]glucose was not different among treatments and was less than ¹⁴CO₂ formation. ¹⁴CO₂ production increased as a function of carbohydrate level but was unrelated to carbohydrate complexity. There was no detectable conversion of [¹⁴C]glucose to lactate for any treatment. Rates of de novo lipogenesis from [1-¹⁴C]acetate were high in comparison to [U-¹⁴C]glucose or [9,10-³H]palmitate incorporation into liver lipids and differed in response to carbohydrate level and complexity. [9,10-³H]palmitate esterification was an order of magnitude less than glycogen and CO₂ production but 4-10 times greater than [¹⁴C]glucose incorporation into liver lipids. Palmitate incorporation did not differ among treatments. Incorporation of [¹⁴C]glucose into liver lipids was higher in fish fed diets containing 400 g kg⁻¹ carbohydrate. These data support the idea that glucose is not a major oxidative substrate in hybrid striped bass and indicate that the level of soluble carbohydrate should be limited to 200 g kg⁻¹ diet or less for hybrid striped bass.
Eric Peatman - One of the best experts on this subject based on the ideXlab platform.
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snp panel development for genetic management of wild and domesticated white bass Morone Chrysops
Animal Genetics, 2019Co-Authors: Honggang Zhao, Adam Fuller, Wilawan Thongda, Haitham H Mohammed, Jason Abernathy, Ben Beck, Eric PeatmanAbstract:White bass (Morone Chrysops), striped bass and their interspecific hybrid are important game fishes, whereas the hybrid striped bass is an important aquaculture species in the US. Numerous state, federal and private hatcheries, therefore, rear these species for stocking purposes as well as for food fish. Although striped bass populations (both wild and domesticated) have been extensively evaluated, relatively little effort has been directed toward the study and improvement of white bass. In this study, we developed SNP resources to examine the genetic relationships among a long-term domesticated white bass line and five potential founder stocks for selective breeding collected from drainages in Arkansas, Texas and Alabama. Using genotyping-by-sequencing, we generated 13 872 genome-wide SNP loci across the six populations. Stringent filtering of SNP-calling parameters identified 426 informative SNP loci. Population genetic and structure analyses using these loci revealed only moderate genetic differentiation between populations (global Fst = 0.083) and indicated two major genetic clusters. A final 57-SNP assay was successfully designed and validated using the MassARRAY system. The developed SNP panel assigned 96 additional genotyped individuals to their population of origin with 100% accuracy. The SNP resources developed in this study should facilitate ongoing efforts in selective breeding and conservation of white bass.
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hepatic transcriptomic and metabolic responses of hybrid striped bass Morone saxatilis Morone Chrysops to acute and chronic hypoxic insult
Comparative Biochemistry and Physiology Part D: Genomics and Proteomics, 2016Co-Authors: Benjamin H. Beck, Steven D Rawles, Honggang Zhao, Adam S Fuller, Bartholomew W Green, Carl D Webster, Eric PeatmanAbstract:Striped bass (Morone saxatilis), white bass (Morone Chrysops), and their hybrid are an important group of fish prized for recreational angling in the United States, and there and abroad as a high-value farmed fish. Regardless of habitat, it is not uncommon for fish of the genus Morone to encounter and cope with conditions of scarce oxygen availability. Previously, we determined that hybrid striped bass reared under conditions of chronic hypoxia exhibited reduced feed intake, lower lipid and nutrient retention, and poor growth. To better understand the molecular mechanisms governing these phenotypes, in the present study, we examined the transcriptomic profiles of hepatic tissue in hybrid striped bass exposed to chronic hypoxia (90days at 25% oxygen saturation) and acute hypoxia (6h at 25% oxygen saturation). Using high-throughput RNA-seq, we found that over 1400 genes were differentially expressed under disparate oxygen conditions, with the vast majority of transcriptional changes occurring in the acute hypoxia treatment. Gene pathway and bioenergetics analyses revealed hypoxia-mediated perturbation of genes and gene networks related to lipid metabolism, cell death, and changes in hepatic mitochondrial content and cellular respiration. This study offers a more comprehensive view of the temporal and tissue-specific transcriptional changes that occur during hypoxia, and reveals new and shared mechanisms of hypoxia tolerance in teleosts.
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Transcriptome annotation and marker discovery in white bass (Morone Chrysops) and striped bass (Morone saxatilis)
Animal genetics, 2014Co-Authors: Benjamin H. Beck, S. Adam Fuller, Eric PeatmanAbstract:Summary Striped bass (Morone saxatilis) and white bass (Morone Chrysops) are the parental species of the hybrid striped bass, a major U.S. aquaculture species. Currently, genomic resources for striped bass, white bass, and their hybrid lag behind those of other aquaculture species. Current resources consist of a medium-density genetic linkage map and a well-annotated ovarian transcriptome. A well-annotated transcriptome from across striped bass and white bass tissues is needed to advance both broad-based RNA-seq studies of gene expression as well as aid in more targeted studies of important genes and pathways critical for reproductive physiology and immunity. Here, we carried out Illumina-based transcriptome sequencing and annotation in both species utilizing the trinity and trinotate packages. The assembled Moronid reference transcriptomes and identified SSRs and SNPs should advance ongoing studies of reproduction, physiology, and immunology in these species and provide markers for broodstock management and selection.
Gerald M Ludwig - One of the best experts on this subject based on the ideXlab platform.
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effect of rotifer enrichment on sunshine bass Morone Chrysops m saxatilis larvae growth and survival and fatty acid composition
Journal of The World Aquaculture Society, 2008Co-Authors: Gerald M Ludwig, Steven D Rawles, Steve E LochmannAbstract:The effect of enriching rotifer prey with highly unsaturated fatty acids on sunshine bass Morone Chrysops × M. saxatilis larval survival and growth from ages 4 to 12 d posthatch was determined. Comparisons were made among larvae fed (1) rotifers cultured with Nannochloropsis paste versus rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000; (2) no rotifers versus rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000; and (3) rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000, rotifers cultured with Nannochloropsis and Pavlova pastes and enriched with Culture Selco 3000, and rotifers cultured with Nannochloropsis paste and enriched with Culture Selco 3000 and Super Selco. The only differences in survival were unfed larvae with practically no survival compared to 55.4% survival for larvae fed rotifers cultured with paste plus Culture Selco 3000. Larvae fed rotifers cultured with paste plus Culture Selco 3000 were longer and had greater condition than those fed rotifers cultured with paste. Additional enrichment with Pavlova sp. or Super Selco had no affect. A canonical analysis of fatty acid contents of diets, rotifers, and fry supported evidence from harvest results. Distances between centroids indicated distinct differences among diets, less distinction among the rotifers, and little difference among fry. Enrichment enhanced growth, but additional enrichment beyond that done during rotifer culture did not increase survival, growth, or condition.
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effect of tank stocking density on larval sunshine bass growth and survival to the fingerling stage
North American Journal of Aquaculture, 2007Co-Authors: Gerald M Ludwig, Steve E LochmannAbstract:Abstract Determining optimum parameters for tank culture of sunshine bass (white bass Morone Chrysops × striped bass M. saxatilis) fingerlings will facilitate a year-round supply of seed for the production cycle of this increasingly popular food fish. This experiment determined the relationship between the stocking density of sunshine bass larvae in tanks and their survival rate and size at the time they were trained to accept commercial feeds. Four-day posthatch (dph) larvae were stocked at 10 densities from 30 to 120 larvae/L in 10-larvae/L increments. Larvae were initially fed rotifers Brachionus plicatilis cultured with Nannochloropsis spp. algae paste and commercial rotifer feed at 60 rotifers·mL−1·d−1 until 10 dph. Conversion to brine shrimp Artemia spp. began at 7 dph. The daily ration of brine shrimp started at 4/mL and increased by 4/mL every 4 d up to 20/mL. Training to dry starter feed began at 20 dph when 6 g/d of a commercial larval starter meal was offered; 2 d later, salmon starter meal was...
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high drift rate effects of propanil and basis gold on the plankton communities and water quality of a prestocking sunshine bass Morone Chrysops m saxatilis fry pond
Journal of Applied Aquaculture, 2007Co-Authors: Peter W Perschbacher, Gerald M LudwigAbstract:ABSTRACT Mesocosm-testing of aerially applied herbicides propanil and Basis Gold (86.8% atrazine) and indicated high drift rates (10–20% of field rates) resulted in adverse impacts on aquaculture production-pond phytoplankton, zooplankton, and critical water-quality variables. Effects on fry pond phytoplankton, zooplankton, and water quality from these herbicides were evaluated at 30% of field application rates, equal to the worst-case scenario from drift to these smaller ponds with consequent higher concentrations. The study was conducted in 12 outdoor pool mesocosms of 500 L volume, filled with pond water from an adjacent 0.1 ha pond fertilized and prepared as recommended for sunshine bass, Morone Chrysops × M. saxatilis, fry stocking. Plankton and water quality samples were taken just prior to herbicide application (day 0) and on days 1,2,3,4-zooplankton only, and on day 7 after application. Field application rates for Basis Gold and propanil were 0.8 kg active ingredient and 1.80 kg/ha, respectively. ...
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hormonal effects on sex differentiation and growth in sunshine bass Morone Chrysops Morone saxatilis
Aquaculture, 2004Co-Authors: Kenneth B Davis, Gerald M LudwigAbstract:Abstract During the production of sunshine bass, the fish are graded several times to avoid loss due to cannibalism. Such grading of fish that may exhibit sexually dimorphic growth could result in changing the sex ratio of populations raised for food production. A preferred gender exists for most aquaculture species. We have found that, during the first year, male sunshine bass appear to grow faster than females; however, females grow faster during the second year and are usually heavier when the fish are harvested. Feeding 17-α-methyltestosterone did not increase the growth of fingerling fish; however, feeding estradiol decreased growth, apparently by decreasing feed consumption. Immersion treatment of 4-day-old fry for up to 8 h with 17α-methyltestosterone or estradiol did not change the sex ratio. Treatment of 60- or 103-day-old fish for 40 days with estradiol in the feed resulted in all female fish. 17α-methyltestosterone treatment during the earlier period resulted in intersex fish, and treatment of 103-day-old fish did not change the sex ratio. Direct feminization with estradiol can be achieved during a period of development in which direct masculinization with 17α-methyltestosterone is not effective.
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tank culture of larval sunshine bass Morone Chrysops rafinesque m saxatilis walbaum at three feeding levels
Aquaculture Research, 2003Co-Authors: Gerald M LudwigAbstract:Sunshine bass, a hybrid of female white bass Morone Chrysops (Rafinesque) and male striped bass M. saxatilis (Walbaum), fingerling production occurs almost exclusively in ponds. To increase production and maintain year-round production in temperate climates, indoor tank culture is required. While tank production of fingerlings has been demonstrated, little is known about feeding requirements. Sunshine bass larvae, stocked at 75 L−1 in 100 L of brackish water, were fed sequentially with rotifers Brachionus plicatilis cultured with a Nannochloropis algae paste and enriched with highly unsaturated fatty acids, decapsulated Artemia nauplii, and a microencapsulated commercial diet. The larvae in one treatment (three replicates) were initially fed rotifers at a daily rate of 20 mL−1, then nauplii at an initial rate of 2 mL−1, and then the commercial diet at 1 g. Larvae in two other treatments received two and three times as much food daily. The highest feeding rate resulted in a survival (52.9%) that was significantly higher than the survival rate (22.4%) of larvae fed the least. The total biomass produced was the highest in the treatment receiving the most food. The lowest feeding rate produced the least fish, but they were the heaviest. The intermediate feeding rate produced the shortest fish (11.3 mm).
Yonathan Zohar - One of the best experts on this subject based on the ideXlab platform.
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hormonal changes in male white bass Morone Chrysops and evaluation of milt quality after treatment wit
Aquaculture, 1997Co-Authors: Costadinos C Mylonas, Ahikam Gissis, Yoav Magnus, Yonathan ZoharAbstract:Abstract Captive white bass (Morone Chrysops) were exposed to an increase in temperature and treated with a gonadotropin-releasing hormone agonist (GnRHa) delivery system during the spermiation period. Circulating levels of various reproductive hormones, and milt production and quality were examined before and after GnRHa treatment. Circulating levels of gonadotropin II (GtH II) prior to GnRHa treatment were below the assay detection limit (0.4 ng ml−1), while mean (± SEM) plasma levels of 17α, 20β-dihydroxy-4-pregnen-3-one (17, 20β-P) were 0.09 ± 0.03 ng ml−1, testosterone (T) levels were 0.79 ± 0.11 ng ml−1 and 11-ketotestosterone (11-KT) levels were 1.7 ± 0.3 ng ml−1. Treatment with the GnRHa delivery system induced significant increases in plasma GtH II and 17,20β-P after 7 days, whereas T and 11-KT were unaffected. Plasma 17α, 20β, 21-trihydroxy-4-pregnen-3-one (17, 20β, 21-P) remained unchanged during the experiment with a mean of 0.55 ± 0.05 ng ml−1. Mean total expressible milt increased significantly after treatment with the GnRHa delivery system, from 2.0 ± 0.1 ml kg−1 body weight on day 0 to 3.6 ± 0.5 ml kg−1 on day 7. Milt production remained constant in saline-injected control fish and averaged 2.1 ± 0.2 ml kg−1. Sperm density, motility and fertilization percentage of total inseminated eggs did not differ between milt from GnRHa- and saline-injected fish, and averaged 52 ± 2 × 109 spermatozoa ml−1, 50 ± 4% motile spermatozoa and 60 ± 5% fertilized eggs, respectively. These results demonstrate the effectiveness of sustained GnRHa treatment in enhancing milt production in white bass, without negatively affecting milt quality. It is assumed that enhancement of milt production is caused by high circulating GtH II levels, via the action of 17, 20β-P.
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hormonal changes in male white bass Morone Chrysops and evaluation of milt quality after treatment wit
Aquaculture, 1997Co-Authors: Costadinos C Mylonas, Ahikam Gissis, Yoav Magnus, Yonathan ZoharAbstract:Abstract Captive white bass ( Morone Chrysops ) were exposed to an increase in temperature and treated with a gonadotropin-releasing hormone agonist (GnRHa) delivery system during the spermiation period. Circulating levels of various reproductive hormones, and milt production and quality were examined before and after GnRHa treatment. Circulating levels of gonadotropin II (GtH II) prior to GnRHa treatment were below the assay detection limit (0.4 ng ml −1 ), while mean (± SEM) plasma levels of 17α, 20β-dihydroxy-4-pregnen-3-one (17, 20β-P) were 0.09 ± 0.03 ng ml −1 , testosterone (T) levels were 0.79 ± 0.11 ng ml −1 and 11-ketotestosterone (11-KT) levels were 1.7 ± 0.3 ng ml −1 . Treatment with the GnRHa delivery system induced significant increases in plasma GtH II and 17,20β-P after 7 days, whereas T and 11-KT were unaffected. Plasma 17α, 20β, 21-trihydroxy-4-pregnen-3-one (17, 20β, 21-P) remained unchanged during the experiment with a mean of 0.55 ± 0.05 ng ml −1 . Mean total expressible milt increased significantly after treatment with the GnRHa delivery system, from 2.0 ± 0.1 ml kg −1 body weight on day 0 to 3.6 ± 0.5 ml kg −1 on day 7. Milt production remained constant in saline-injected control fish and averaged 2.1 ± 0.2 ml kg −1 . Sperm density, motility and fertilization percentage of total inseminated eggs did not differ between milt from GnRHa- and saline-injected fish, and averaged 52 ± 2 × 10 9 spermatozoa ml −1 , 50 ± 4% motile spermatozoa and 60 ± 5% fertilized eggs, respectively. These results demonstrate the effectiveness of sustained GnRHa treatment in enhancing milt production in white bass, without negatively affecting milt quality. It is assumed that enhancement of milt production is caused by high circulating GtH II levels, via the action of 17, 20β-P.
Benjamin H. Beck - One of the best experts on this subject based on the ideXlab platform.
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hepatic transcriptomic and metabolic responses of hybrid striped bass Morone saxatilis Morone Chrysops to acute and chronic hypoxic insult
Comparative Biochemistry and Physiology Part D: Genomics and Proteomics, 2016Co-Authors: Benjamin H. Beck, Steven D Rawles, Honggang Zhao, Adam S Fuller, Bartholomew W Green, Carl D Webster, Eric PeatmanAbstract:Striped bass (Morone saxatilis), white bass (Morone Chrysops), and their hybrid are an important group of fish prized for recreational angling in the United States, and there and abroad as a high-value farmed fish. Regardless of habitat, it is not uncommon for fish of the genus Morone to encounter and cope with conditions of scarce oxygen availability. Previously, we determined that hybrid striped bass reared under conditions of chronic hypoxia exhibited reduced feed intake, lower lipid and nutrient retention, and poor growth. To better understand the molecular mechanisms governing these phenotypes, in the present study, we examined the transcriptomic profiles of hepatic tissue in hybrid striped bass exposed to chronic hypoxia (90days at 25% oxygen saturation) and acute hypoxia (6h at 25% oxygen saturation). Using high-throughput RNA-seq, we found that over 1400 genes were differentially expressed under disparate oxygen conditions, with the vast majority of transcriptional changes occurring in the acute hypoxia treatment. Gene pathway and bioenergetics analyses revealed hypoxia-mediated perturbation of genes and gene networks related to lipid metabolism, cell death, and changes in hepatic mitochondrial content and cellular respiration. This study offers a more comprehensive view of the temporal and tissue-specific transcriptional changes that occur during hypoxia, and reveals new and shared mechanisms of hypoxia tolerance in teleosts.
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Transcriptome annotation and marker discovery in white bass (Morone Chrysops) and striped bass (Morone saxatilis)
Animal genetics, 2014Co-Authors: Benjamin H. Beck, S. Adam Fuller, Eric PeatmanAbstract:Summary Striped bass (Morone saxatilis) and white bass (Morone Chrysops) are the parental species of the hybrid striped bass, a major U.S. aquaculture species. Currently, genomic resources for striped bass, white bass, and their hybrid lag behind those of other aquaculture species. Current resources consist of a medium-density genetic linkage map and a well-annotated ovarian transcriptome. A well-annotated transcriptome from across striped bass and white bass tissues is needed to advance both broad-based RNA-seq studies of gene expression as well as aid in more targeted studies of important genes and pathways critical for reproductive physiology and immunity. Here, we carried out Illumina-based transcriptome sequencing and annotation in both species utilizing the trinity and trinotate packages. The assembled Moronid reference transcriptomes and identified SSRs and SNPs should advance ongoing studies of reproduction, physiology, and immunology in these species and provide markers for broodstock management and selection.
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lysine optimization of a commercial fishmeal free diet for hybrid striped bass Morone Chrysops m saxatilis
Aquaculture, 2013Co-Authors: Steven D Rawles, Benjamin H. Beck, Gibson T Gaylord, Adam S Fuller, Frederic T Barrows, Matthew E McentireAbstract:article i nfo Substitution of fishmeal with alternate proteins in aquafeeds often results in dietary imbalances of first-limiting essential amino acids (EAA) and poorer fish performance. This growth trial was undertaken totest thehypothesis thatideal proteintheory accurately predicts first-limiting amino acids and optimum lysine level for a fishmeal-free, commercial-grade diet formulated for hybrid striped bass (HSB). The ideal model for formulation was the amino acid pattern of hybrid striped bass muscle. A negative control diet based on soybean (45%), corn gluten (10%), and poultry by-product (13%) meals was formulated on an ideal basis to contain 18% lipid, 40% crude protein (CP), 36% digestible protein (DP) and 1.8% Lys from intact sources. Met and Thr were then added at levels equivalent to 40% protein from HSB muscle to form a basal diet that was fortified with seven levels of Lys (2.2 to 6.4 g/g diet) that bracketed the predicted ideal Lys requirement (3.5 g/g diet) for this formulation. Diets were extruded to achieve similar characteristics as a commercial-grade feed and fed to juvenile fish (118 g BW) for 84 d. Response data were subjected to polynomial and exponential regression and thebestmodelper response selectedbasedonthe lowesterror(MSE) andp-values and thehighestadjusted R 2 . Selected models were used to derive dietary Lys levels required to reach 95% (R95) or 99% (R99) of the minimum or maximum response. Final fish weights (328-369 g) increased linearly with increasing dietary Lys. Weight gain, average daily feed intake (1.42-1.7%), and feed efficiencies at 4-, 8-, and 12-week intervals were modeled by cubic functions that yielded consistent R95 and R99 levels of about 2.4 and4.3 g Lys/g diet, respectively. These values evenly bracketed the predicted ideal Lys requirement. Slightly higher Lys requirement was found for optimum FE at 4 weeks and smaller fish,asopposedto8or12 weeksandlargerfish. Whole body composition was unresponsive to diet Lys level; however, higher dietary Lys was required to minimize liver size (4.8 to 5.2 g Lys/g diet) than to minimize body fat (2.5 to 3.1 g Lys/g diet) or maximize muscle ratio (1.8 to 3.9 g Lys/g diet). Whole body protein, lipid, energy, and EAA retentions were also consistent with cubic functions that generally confirmed the predicted ideal Lys requirement with notable exceptions. Retention of Lys decreased exponentially with increasing dietary Lys, whereas, Met retention decreased in a linear fashion, corroborating that Met was first-limiting in this diet formula, as predicted. Retention of Thr and branched-chain amino acids were optimized at higher Lys levels (3.9-4.5 g/g diet) than those required to maximize growth parameters. Protein accretion (g/fish/d)respondedquadraticallytoLys intakepredicting maximumdeposition at0.10to 0.16 g Lys/fish/d. His- tological assessment of intestines in fish fed these high-soybean meal test diets did not reveal any lesions asso- ciated with enteritis for any diet and overall normal intestinal morphology was observed in all fish sampled. Published by Elsevier B.V.