About

Russell J Borski is a Professor in the Department of Biological Sciences at NC State University. The page does not provide specific details about his research focus, background, or key contributions. Therefore, no further biographical information is available from the provided content.

Research topics

• Fishery
• Biology
• Ecology
• Animal science
• Agronomy
• Internal medicine
• Endocrinology
• Zoology

Selected publications

• Effects of reduced-frequency feeding in the grow out of domesticated Striped Bass in recirculating aquaculture

  North American Journal of Aquaculture · 2026-05-05

  articleOpen accessSenior author

  Abstract Objective The Striped Bass Morone saxatilis is an emerging cultivar in the United States due in large part to its rapid growth rate and the ability to be reared in salinities ranging from freshwater to full-strength seawater. The successful culture of this species has been advanced by successive generations of selective breeding and domestication that have improved growth characteristics by around 8% per generation. Previous studies have shown that implementing reduced feeding protocols in aquaculture can have minimal impact on growth performance while potentially improving feed efficiency. Therefore, we evaluated the growth of fifth-generation, selectively bred pure-strain Striped Bass and determined whether reduced-frequency feeding might improve production efficiency of fish in recirculating aquaculture systems (RASs). Methods We evaluated the production characteristics of F5-generation domesticated Striped Bass that were cyclically fed either 3 d/week or 5 d/week in an RAS. Striped Bass fingerlings were stocked (n = 30 fish/tank) at an average body weight (BW) of 60 g and were fed a commercial diet to satiation once per feeding day. Sampling occurred at the beginning of the study (0 d poststocking [dps]) and then every 2–3 months (i.e., at 58, 113, 179, 262, and 351 dps). Results We found that F5-generation domesticated Striped Bass grew to market size (1.3 kg) in 11–12 months (18 months posthatch) when fed 5 d/week in an RAS. Within 179 dps, the mean BW of fish fed 5 d/week was significantly greater than that of fish fed 3 d/week, and this divergence in size persisted throughout the course of the study. Fish that were fed 3 d/week achieved a final BW (1.1 kg) that was 16% lower than the BW of fish fed 5 d/week, and they consumed 18% less feed overall. Although the specific growth rates of fish on the reduced-frequency feeding regime were lower initially, by 179 dps their growth had reached rates similar to those of fish fed 5 d/week. The final feed conversion ratio (FCR) was not significantly different between feeding regimes. However, the FCR changed with age: It was initially higher in smaller fish fed 3 d/week, whereas by the end of the study, the FCR had subsequently declined to a level at or below the FCR of fish fed 5 d/week. The shift in FCR occurred at a BW of around 785 g. Conclusions Collectively, the results suggest that a shift to reduced-frequency feeding in larger fish (∼785 g) may have the potential to reduce feed and labor costs while minimizing impacts on growth and improving overall production efficiency of domesticated Striped Bass grown in RASs. This study demonstrates that F5-generation, selectively bred Striped Bass can be grown rapidly (<12 months) in an RAS from 60 g to 1.3 kg, a size exceeding that of most domestically produced fish in the United States, which could allow for expansion of aquaculture to the high-value fillet market.

  PublisherDOI

• Embryo and Larval Developmental Staging Guides for Striped Bass

  Fishes · 2026-04-16

  articleOpen access

  Reliable developmental benchmarks are essential for synchronizing incubation and first-feeding decisions in striped bass (Morone saxatilis) hatcheries, yet existing references are incomplete, outdated, or difficult to apply across variable temperature regimes. We developed contemporary embryo and larval developmental staging guides for striped bass using digital imaging and degree day standardization and paired these guides with measurements of early larval mortality and endogenous energy depletion to provide practical context for hatchery management. Larvae were photographed from hatch through metamorphosis to document key morphological transitions, including yolk absorption, mouth formation, swim bladder inflation, fin differentiation, pigmentation, and diet-related developmental milestones. To place these stages in physiological and survival context, aquarium trials showed there was no clear density-dependent mortality across rearing densities of 1.1–6.8 larvae/mL within the first 72 h post-hatch. Yolk reserves were typically depleted by approximately 4–6 days post-hatch (dph), while lipid droplets persisted longer as secondary endogenous energy stores in unfed larvae through 15 dph. Together, these staging guides provide a transferable developmental framework from fertilization to metamorphosis that links external morphology to endogenous reserve depletion and first feeding, thus supporting standardized hatchery monitoring, improved feeding synchronization, and more consistent assessment of embryo and larval quality.

  PublisherDOI

• Evaluation of Pondside Tank Rearing Systems for Juvenile Striped Bass Production

  SSRN Electronic Journal · 2025-01-01 · 1 citations

  preprintOpen access
  PublisherDOI

• The Efficacy of a Novel Selection of Bacillus spp. on Reducing Off-Flavor Compounds and Improving Flesh Quality

  Water · 2025-04-30

  articleOpen access

  Geosmin (GSM) and 2-methylisoborneol (2-MIB), microbial-derived terpenoid compounds prevalent in aquaculture systems, impair fillet quality and disrupt physiological homeostasis in aquatic species by inducing oxidative stress and lipid peroxidation. Despite their significant impact, effective strategies for eliminating these compounds from fish tissues remain underexplored. In this study, we employed primer-mediated PCR amplification to identify strains that produce 2-MIB and GSM and evaluated the efficacy of Bacillus licheniformis strain BL23 (BL23) in suppressing S. thermocarboxydus (ST), a key contributor to terpenoid synthesis. Experimental fish were allocated to three groups (n = 30 per group): Group C (control, standard feed), Group T1 (BL23-supplemented feed), and Group T2 (BL23 + ST coculture). Probiotic concentrations in the tanks were maintained at 106 CFU/mL under controlled conditions (30 °C). Tissue and aqueous samples were collected at intervals for the analysis of texture, growth performance, and terpenoid concentrations, with measurements in triplicate. Subsequently, B. licheniformis strain BL23 (BL23), which exhibits inhibitory effects against S. thermocarboxydus (ST) growth, was cultured and introduced into both fish specimens and aqueous systems. The outcomes of strain inoculation and cultivation experiments demonstrated the emergence of an inhibition zone surrounding the actinomycetes inoculated with BL23. The results from liquid coculture assays revealed a reduction in the concentration of ST from 106 CFU/mL at 48 h to 101 CFU/mL at 72 h post-coculture with BL23 for an initial 48 h period. An analysis of fish tissue and aqueous samples confirmed that BL23 exhibited a significant inhibitory effect on the growth of ST, leading to a substantial decrease in GSM content (p < 0.05). However, no statistically significant improvements were observed in fish growth performance (weight gain, feed conversion rate) or meat texture quality parameters (hardness, elasticity). These findings present a novel approach to mitigating geosmin-induced off-flavors in aquaculture products, highlighting its potential utility in water management and aquatic food production systems. The results are particularly pertinent for the development of biological control strategies targeting microbial-derived odorants in recirculating aquaculture systems.

  PublisherOA PDFDOI

• Evaluation of Pondside Tank Rearing Systems for Juvenile Striped Bass Production

  Aquaculture Reports · 2025-01-01

  articleOpen access

  Larval rearing is one of the main bottlenecks that limits large-scale Striped bass (Morone saxatilis) production in aquaculture. We evaluated a pondside tank approach that combined earthen pond productivity with tank culture to improve early larval survival and water-use efficiency. A pondside tank system consisting of six 414 L tanks received inflow of zooplankton-rich pond water in a series of four trials that assessed: 1) stocking density (12 fry/L, 36 fry/L, 60 fry/L); 2) light trap versus no light trap at pump intakes; 3) partial shading versus no shading; and 4) a reduced density and light trap production trial (<5 fry/L). Pond monitoring used to guide fry stocking showed phytoplankton establishment by 2-3 days post-filling (dpf) and peak rotifer abundance at 9-11 dpf. Lower density in tanks increased survival compared to higher density treatments, while light traps concentrated rotifers and copepods and produced higher survival trends; shading had no measurable effect on survival. A reduced density light trap production trial yielded the best performance (52% survival), whereas traditional earthen ponds harvests had a fry survival rate of 8%. Pondside tanks were >8,000 times more water efficient based on fish produced per liter of water used, and annual energy costs per tank system were <$75.00 USD. Synchronizing fry stocking with peak rotifer abundance, reducing initial stocking density, and adding light to attract live prey improved early larval survival with minimal infrastructure. Pondside tanks provide a practical and potentially scalable path to more consistent and resource-efficient Striped Bass production.

  PublisherDOI

• Gonadal Transcriptome Differences Between the Sexes in Wild Caught Southern Flounder ( <i>Paralichthys lethostigma)</i> During a Critical Development Period

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-22

  preprintOpen access

  Abstract Flounder in the genus Paralichthys exhibit a unique sex determination system that combines genotypic and temperature-dependent mechanisms. In southern flounder ( Paralichthys lethostigma ), XY individuals develop as males, while XX individuals’ sex is influenced by juvenile developmental temperatures. Little is known about the genes involved in this process. This study uses pooled RNA sequencing to create a de novo gonadal transcriptome and identify genes related to sex determination and differentiation in wild-caught juvenile southern flounder from two North Carolina locations with differing sex ratios. The transcriptome assembly revealed 68,331 uniquely annotated genes with high functional specificity. Nine genes were linked to sex determination, including five novel to southern flounder and associated with epigenetic mechanisms like m6a methylation and alternative splicing, suggesting epigenetic influence in male development. Additionally, genes in the TGF-β signaling pathway were differentially expressed, supporting this pathway’s role in sex differentiation. This study provides a valuable transcriptome resource for future research on southern flounder.

  PublisherDOI

• Temperature regulates sex determination and growth in the paralichthid flatfish California halibut

  Journal of Experimental Zoology Part A Ecological and Integrative Physiology · 2024-04-29 · 3 citations

  article

  California halibut (Paralichthys californicus) is a candidate species for aquaculture and stock enhancement. These applications rely on sex control, either to maximize the production of faster growing females or to match sex ratios in the wild. Other paralichthids exhibit temperature-dependent sex determination (TSD), but the presence and pattern of TSD is not well defined in California halibut. Juvenile California halibut were cultured at three distinct temperatures (15°C, 19°C, and 23°C) through the developmental period presumed to be thermosensitive based on findings from congeners. Sex ratios were quantified in each treatment using phenotypic sex identification techniques applied early (molecular biomarkers; 51-100 mm total length [TL]) and late (visual examination of the gonads; ≥100 mm TL) in the juvenile phase. Both techniques indicated similar sex determination trends at each temperature, with overall sex ratios assessed as 49.9% male at 15°C, 74.5% male at 19°C, and 98.2% male at 23°C. Growth rates were highest at 23°C and lowest at 15°C, with intrinsically fast- and slow-growing individuals at all temperatures. At 15°C and 19°C, females comprised a higher proportion among the fast growers than they did among the slow growers. These data show that California halibut exhibit TSD, with temperatures of 19°C and 23°C masculinizing fish while 15°C appears to produce a 1:1 sex ratio. This study will help optimize sex ratios and growth in hatcheries through thermal manipulation. Furthermore, the developed biomolecular tools and identified temperature thresholds will be important in future work to understand the influence of global warming on wild population demographics.

  PublisherDOI

• Impacts of integration of mola with prawn–carp gher farming: An approach to enhance household fish consumption and family income

  Journal of the World Aquaculture Society · 2024-03-17 · 2 citations

  articleOpen access

  Abstract This study investigated the production performance, household fish consumption, and commercial feasibility of prawn–carp–mola mixed gher farming system. Three treatments with different species compositions were compared: prawn + rohu, prawn + mola, and prawn + rohu + mola, each having different stocking densities. The results indicated that the integration of mola improved the utilization of feed protein by prawns. However, mola inclusion did not significantly affect the growth of prawn and rohu or the production system's cost. Mola inclusion led to a significant increase in the gross production, household consumption, and sale of mola, prawn, and rohu. It also increased gross returns, income above variable cost, and net returns to land, family labor, and management. In addition, the inclusion of mola significantly increased household consumption by increasing the intake of nutrient‐rich mola and overall fish consumption. This improvement in food consumption contributed to ensuring the nutritional requirements and food security of impoverished rural farmers, especially women and children. Consequently, the integration of small fish mola in prawn–carp gher farming systems is recommended as a beneficial practice for wider adoption, effectively addressing household nutrition security at the rural level and improving the livelihoods of farmers.

  PublisherOA PDFDOI

• Combinatorial metabolomic and transcriptomic analysis of muscle growth in hybrid striped bass (female white bass Morone chrysops x male striped bass M. saxatilis)

  BMC Genomics · 2024-06-10 · 10 citations

  articleOpen access

  Abstract Background Understanding growth regulatory pathways is important in aquaculture, fisheries, and vertebrate physiology generally. Machine learning pattern recognition and sensitivity analysis were employed to examine metabolomic small molecule profiles and transcriptomic gene expression data generated from liver and white skeletal muscle of hybrid striped bass (white bass Morone chrysops x striped bass M. saxatilis ) representative of the top and bottom 10 % by body size of a production cohort. Results Larger fish (good-growth) had significantly greater weight, total length, hepatosomatic index, and specific growth rate compared to smaller fish (poor-growth) and also had significantly more muscle fibers of smaller diameter (≤ 20 µm diameter), indicating active hyperplasia. Differences in metabolomic pathways included enhanced energetics (glycolysis, citric acid cycle) and amino acid metabolism in good-growth fish, and enhanced stress, muscle inflammation (cortisol, eicosanoids) and dysfunctional liver cholesterol metabolism in poor-growth fish. The majority of gene transcripts identified as differentially expressed between groups were down-regulated in good-growth fish. Several molecules associated with important growth-regulatory pathways were up-regulated in muscle of fish that grew poorly: growth factors including agt and agtr2 (angiotensins), nicotinic acid (which stimulates growth hormone production), gadd45b, rgl1, zfp36 , cebpb, and hmgb1 ; insulin-like growth factor signaling ( igfbp1 and igf1 ); cytokine signaling ( socs3 , cxcr4 ); cell signaling ( rgs13 , rundc3a ), and differentiation ( rhou, mmp17, cd22, msi1 ); mitochondrial uncoupling proteins ( ucp3 , ucp2 ); and regulators of lipid metabolism ( apoa1 , ldlr ). Growth factors pttg1 , egfr , myc , notch1 , and sirt1 were notably up-regulated in muscle of good-growing fish. Conclusion A combinatorial pathway analysis using metabolomic and transcriptomic data collectively suggested promotion of cell signaling, proliferation, and differentiation in muscle of good-growth fish, whereas muscle inflammation and apoptosis was observed in poor-growth fish, along with elevated cortisol (an anti-inflammatory hormone), perhaps related to muscle wasting, hypertrophy, and inferior growth. These findings provide important biomarkers and mechanisms by which growth is regulated in fishes and other vertebrates as well.

  PublisherOA PDFDOI

• Southern Flounder: Major Milestones and Remaining Knowledge Gaps in Their Biology, Ecology, and Fishery Management

  Reviews in Fisheries Science & Aquaculture · 2024-05-07 · 3 citations

  articleOpen access

  Southern flounder are an iconic coastal finfish through the Southeast U.S. Atlantic and Gulf of Mexico. Southern flounder spend the early part of their lives in coastal and estuarine habitats, later moving offshore to spawn. Several decades of research have provided much clarity to the biology, life history, and aquaculture aspects of southern flounder—this information is summarized and reviewed in this study. Despite substantial improvement in understanding the species, major questions remain about their recruitment, offshore behaviors, captive rearing, and management. Recently, southern flounder have also been in focus because of substantial synchronous population declines throughout their range with specific concerns that recruitment failure and possibly climate change may be implicated. Management of southern flounder has thus far taken place within individual states, but coming into focus is the possibility that larger coastwide management approaches may need to be considered due to both the migratory nature of the species and the possibility of population stressors acting at regional scales. Many states have already begun aquaculture and enhancement efforts, with an eye toward supplementing wild populations. Large group efforts, like the symposium that led to this study, will likely be needed to tackle the complex challenges confronting southern flounder.

  PublisherOA PDFDOI

Recent grants

• NIH Grant F32DK009008

  NIH · $28k

• Stimulus-Secretion Coupling Mechanisms for Rapid, Nongenomic Corticosteroid Actions in the Teleost Prolactin Cell Model System

  NSF · $379k · 2002–2007

• Prolactin Secretion in a Teleost Fish: Elucidation of Novel Mechanisms for Rapid Steroid Hormone Action

  NSF · $248k · 1998–2002

• Function and Regulation of Leptin in Mediating Stress-induced Energy Expenditure

  NSF · $631k · 2015–2021

Frequent coauthors

• E. Gordon Grau

  23 shared

• Christian K. Tipsmark

  University of Arkansas at Fayetteville

  21 shared

• Matthew E. Picha

  The University of Texas at Austin

  19 shared

• Steffen S. Madsen

  15 shared

• Marc J. Turano

  Cargill (United States)

  14 shared

• J. Adam Luckenbach

  Washington State University

  14 shared

• David A. Baltzegar

  North Carolina State University

  13 shared

• John Godwin

  North Carolina State University

  11 shared