Bioconcentration and toxicity of perfluoroalkyl substances (PFAS) in embryonic stages of the ecologically and commercially relevant Olive Flounder (Paralichthys olivaceus), and the zebrafish (Danio rerio) embryo model system.

Polyfluoroalkyl substances (PFAS) are ubiquitous in aquatic habitats, and there are emerging concerns that these chemicals may pose risks to organisms in these ecosystems. The present study investigated bioconcentration and toxicity of PFAS including the "legacy" congener, perfluorooctanoic acid (PFOA), and seven long- and short-chain perfluoroether carboxylic acids (PFECA) in embryonic stages of both zebrafish (Danio rerio), as an established laboratory model, and Olive Flounder (Paralichthys olivaceus), as a relevant marine fish species. Bioconcentration factors were determined for both species with BCF values ranging from 22 to 1741 L kg.

The role of marine fish-produced carbonates in the oceanic carbon cycle is determined by size, specific gravity, and dissolution rate.

Rising CO emissions have heightened the necessity for increased understanding of Earth's carbon cycle to predict future climates. The involvement of marine planktonic species in the global carbon cycle has been extensively studied, but contributions by marine fish remain poorly characterized. Marine teleost fishes produce carbonate minerals ('ichthyocarbonates') within the lumen of their intestines which are excreted at significant rates on a global scale.

High-Resolution Magic Angle Spinning (HRMAS) NMR Identifies Oxidative Stress and Impairment of Energy Metabolism by Zearalenone in Embryonic Stages of Zebrafish (), Olive Flounder () and Yellowtail Snapper ().

Zearalenone (ZEA) is a mycotoxin, commonly found in agricultural products, linked to adverse health impacts in humans and livestock. However, less is known regarding effects on fish as both ecological receptors and economically relevant "receptors" through contamination of aquaculture feeds. In the present study, a metabolomics approach utilizing high-resolution magic angle spinning nuclear magnetic resonance (HRMAS NMR) was applied to intact embryos of zebrafish (), and two marine fish species, olive flounder () and yellowtail snapper (), to investigate the biochemical pathways altered by ZEA exposure.

Brief Oil Exposure Reduces Fitness in Wild Gulf of Mexico Mahi-Mahi ().

The (DWH) disaster released 3.19 million barrels of crude oil into the Gulf of Mexico (GOM) in 2010, overlapping the habitat of pelagic fish populations. Using mahi-mahi ()─a highly migratory marine teleost present in the GOM during the spill─as a model species, laboratory experiments demonstrate injuries to physiology and behavior following oil exposure.

Toxicity of perfluoroalkyl substances (PFAS) toward embryonic stages of mahi-mahi (Coryphaena hippurus).

Perfluoroalkyl substances (PFAS) are highly persistent organic pollutants that have been detected in a wide array of environmental matrices and, in turn, diverse biota including humans and wildlife wherein they have been associated with a multitude of toxic, and otherwise adverse effects, including ecosystem impacts. In the present study, we developed a toxicity assay for embryonic stages of mahi-mahi (Coryphaena hippurus), as an environmentally relevant pelagic fish species, and applied this assay to the evaluation of the toxicity of "legacy" and "next-generation" PFAS including, respectively, perfluorooctanoic acid (PFOA) and several perfluoroethercarboxylic acids (PFECA). Acute embryotoxicity, in the form of lethality, was measured for all five PFAS toward mahi-mahi embryos with median lethal concentrations (LC) in the micromolar range.

Enhanced oxygen unloading in two marine percomorph teleosts.

Teleost fishes are diverse and successful, comprising almost half of all extant vertebrate species. It has been suggested that their success as a group is related, in part, to their unique O transport system, which includes pH-sensitive hemoglobin, a red blood cell β-adrenergic Na/H exchanger (RBC β-NHE) that protects red blood cell pH, and plasma accessible carbonic anhydrase which is absent at the gills but present in some tissues, that short-circuits the β-NHE to enhance O unloading during periods of stress. However, direct support for this has only been examined in a few species of salmonids.

Ultraviolet avoidance by embryonic buoyancy control in three species of marine fish.

Pelagic fish embryos are thought to float in or near surface waters for the majority of their development and are presumed to have little to no control over their mobility, rendering these embryos at high risk for damages associated with surface stressors such as ultraviolet radiation (UVR). We recently challenged these long-standing paradigms by characterizing a potential mechanism of stressor avoidance in early-life stage mahi-mahi (Coryphaena hippurus) in which embryos sense external cues, such as UVR, and modify their buoyancy to reduce further exposure. It is unknown whether embryos of other marine fish with pelagic spawning strategies have similar capabilities.

An integrated systems-level model of the toxicity of brevetoxin based on high-resolution magic-angle spinning nuclear magnetic resonance (HRMAS NMR) metabolic profiling of zebrafish embryos.

Brevetoxins (PbTx) are a well-recognized group of neurotoxins associated with harmful algal blooms, and specifically recurrent "Florida Red Tides," in marine waters that are linked to impacts on both human and ecosystem health including well-documented "fish kills" and marine mammal mortalities in affected coastal waters. Understanding mechanisms and pathways of PbTx toxicity enables identification of relevant biomarkers to better understand these environmental impacts, and improve monitoring efforts, in relation to this toxin. Toward a systems-level understanding of toxicity, and identification of potential biomarkers, high-resolution magic angle spinning nuclear magnetic resonance (HRMAS NMR) was utilized for metabolic profiling of zebrafish (Danio rerio) embryos, as an established toxicological model, exposed to PbTx-2 (the most common congener in marine waters).

The effects of acute temperature change and digestive status on in situ cardiac function in mahi-mahi (Coryphaena hippurus).

In this study, we investigated the effect of acute increases in temperature on cardiovascular function of mahi-mahi (Coryphaena hippurus). We also describe, for the first time, an artery that supplies the gastrointestinal tract that originates from the fourth branchial artery. We used vascular casting to verify the anatomical location of this unique celiaco-mesenteric artery.

Exposure to Hydraulic Fracturing Flowback Water Impairs () Cardiomyocyte Contractile Function and Swimming Performance.

Publicly available toxicological studies on wastewaters associated with unconventional oil and gas (UOG) activities in offshore regions are nonexistent. The current study investigated the impact of hydraulic fracturing-generated flowback water (HF-FW) on whole organism swimming performance/respiration and cardiomyocyte contractility dynamics in mahi-mahi (-hereafter referred to as "mahi"), an organism which inhabits marine ecosystems where offshore hydraulic fracturing activity is intensifying. Following exposure to 2.

Temperature sensitivity differs between heart and red muscle mitochondria in mahi-mahi (Coryphaena hippurus).

Maintaining energy balance over a wide range of temperatures is critical for an active pelagic fish species such as the mahi-mahi (Coryphaena hippurus), which can experience rapid changes in temperature during vertical migrations. Due to the profound effect of temperature on mitochondrial function, this study was designed to investigate the effects of temperature on mitochondrial respiration in permeabilized heart and red skeletal muscle (RM) fibres isolated from mahi-mahi. As RM is thought to be more anatomically isolated from rapid ambient temperature changes compared to the myocardium, it was hypothesized that heart mitochondria would be more tolerant of temperature changes through a greater ability to match respiratory capacity to an increase in temperature and to maintain coupling, when compared to RM mitochondria.

Intra-Specific Difference in the Effect of Salinity on Physiological Performance in European Perch () and Its Ecological Importance for Fish in Estuaries.

Changes in environmental salinity challenge fish homeostasis and may affect physiological performance, such as swimming capacity and metabolism, which are important for foraging, migration, and escaping predators in the wild. The effects of salinity stress on physiological performance are largely species specific, but may also depend on intra-specific differences in physiological capabilities of sub-populations. We measured critical swimming speed (U) and metabolic rates during swimming and at rest at salinities of 0 and 10 in European perch () from a low salinity tolerance population (LSTP) and a high salinity tolerance population (HSTP).

Exposure to Crude Oil from the Oil Spill Impairs Oil Avoidance Behavior without Affecting Olfactory Physiology in Juvenile Mahi-Mahi ().

The understanding of the detection threshold and behavioral response of fishes in response to crude oil is critical to predicting the effects of oil spills on wild fish populations. The oil spill released approximately 4.9 million barrels of crude oil into the northern Gulf of Mexico in 2010, overlapping spatially and temporally with the habitat of many pelagic fish species.

Impacts of Crude Oil on Mahi-Mahi () Heart Cell Function.

crude oil is comprised of polycyclic aromatic hydrocarbons that cause a number of cardiotoxic effects in marine fishes across all levels of biological organization and at different life stages. Although cardiotoxic impacts have been widely reported, the mechanisms underlying these impairments in adult fish remain understudied. In this study, we examined the impacts of crude oil on cardiomyocyte contractility and electrophysiological parameters in freshly isolated ventricular cardiomyocytes from adult mahi-mahi ().

Mahi-mahi (Coryphaena hippurus) life development: morphological, physiological, behavioral and molecular phenotypes.

Background: Mahi-mahi (Coryphaena hippurus) is a commercially and ecologically important fish species that is widely distributed in tropical and subtropical waters. Biological attributes and reproductive capacities of mahi-mahi make it a tractable model for experimental studies. In this study, life development of cultured mahi-mahi from the zygote stage to adult has been described.

Deepwater Horizon crude oil exposure alters cholesterol biosynthesis with implications for developmental cardiotoxicity in larval mahi-mahi (Coryphaena hippurus).

During the spring and summer of 2010, the Deepwater Horizon (DWH) oil well released over three million barrels of crude oil into the Gulf of Mexico. As the oil dispersed it contaminated ecosystems that support numerous Gulf species including mahi-mahi (Coryphaena hippurus). The timing of the spill, and location of the surface slick, coincided with the spawning of many species in the region, raising concerns over embryonic and larval exposure.

Acute crude oil exposure alters mitochondrial function and ADP affinity in cardiac muscle fibers of young adult Mahi-mahi (Coryphaena hippurus).

Mitochondrial function is critical to support aerobic metabolism through the production of ATP, and deficiencies in mitochondrial bioenergetics will directly impact the performance capacity of highly aerobic tissues such as the myocardium. Cardiac function in fish has been shown to be negatively affected by crude oil exposure, however, the mechanism for this adverse response is largely unexplored. We hypothesized that lipophilic polycyclic aromatic hydrocarbons (PAHs) found in crude oil disrupt the electron transport system (ETS) ultimately leading to mitochondrial dysfunction.

Embryonic buoyancy control as a mechanism of ultraviolet radiation avoidance.

Pelagic fish have long been presumed to produce buoyant embryos which float and hatch at or near surface waters. Due to their transparency and rapid development, mahi embryos are thought to be especially vulnerable to stressors occurring in surface waters, such as ultraviolet radiation (UVR) and increased temperatures. In the present study, we suggest a possibly critical mechanism of UVR avoidance by pelagic fish embryos.

Combined effects of elevated temperature and Deepwater Horizon oil exposure on the cardiac performance of larval mahi-mahi, Coryphaena hippurus.

The 2010 Deepwater Horizon oil spill coincided with the spawning season of many pelagic fish species in the Gulf of Mexico. Yet, few studies have investigated physiological responses of larval fish to interactions between anthropogenic crude oil exposure and natural factors (e.g.

Combined effects of hypoxia or elevated temperature and Deepwater Horizon crude oil exposure on juvenile mahi-mahi swimming performance.

This study examined potential interactive effects of co-exposure to Deepwater Horizon (DWH) crude oil (∼30 μg L ΣPAHs) for 24 h and either hypoxia (2.5 mg O L; 40% O saturation) or elevated temperature (30 °C) on the swimming performance of juvenile mahi-mahi (Coryphaena hippurus). Additionally, effects of shorter duration exposures to equal or higher doses of oil alone either prior to swimming or during the actual swim trial itself were examined.

A comparison of hatchery-rearing in exercise to wild animal physiology and reflex behavior in Aplysia californica.

Aplysia californica was hatchery-reared in two turbulence protocols intended to imitate the intermittent turbulence of the native habitat and to promote development of the foot muscle from the exercise of adhering to the substrate. Hatchery-reared animals in turbulence regimes were compared to siblings reared in quiet water, and to wild animals, using noninvasive assessments of the development of the foot muscle. The objective was to learn if the turbulence-reared phenotype mimicked laboratory-targeted aspects of the wild phenotype, that is, reflex behavior, swim tunnel performance, and resting oxygen consumption (MO).

Nutritional physiology of mahi-mahi (Coryphaena hippurus): Postprandial metabolic response to different diets and metabolic impacts on swim performance.

Migratory pelagic fish species, such as the mahi-mahi (Coryphaena hippurus), must balance numerous metabolic demands simultaneously in order to survive in a challenging oceanic environment. Energetic support for such demands comes from a variety of natural prey items in the wild and can come from manufactured pelletized feed in captivity. This study quantified postprandial metabolism, commonly referred to as specific dynamic action (SDA), over time in adult mahi-mahi (706±25g; 38±0.