Physiology Commons^™

Internal Vertebral Morphology Of Bony Fishes Matches The Mechanical Demands Of Different Environments, Dana Baxter, Karly E. Cohen, Cassandra M. Donatelli, Eric D. Tytell

Engineering Faculty Articles and Research

Fishes have repeatedly evolved characteristic body shapes depending on how close they live to the substrate. Pelagic fishes live in open water and typically have narrow, streamlined body shapes; benthic and demersal fishes live close to the substrate; and demersal fishes often have deeper bodies. These shape differences are often associated with behavioral differences: pelagic fishes swim nearly constantly, demersal fishes tend to maneuver near the substrate, and benthic fishes often lie in wait on the substrate. We hypothesized that these morphological and behavioral differences would be reflected in the mechanical properties of the body, and specifically in vertebral column …

Development Of A High Throughput, Whole Organism Assay For Studying Metabolic Capacity In Crassostrea Virginica, Avuntaura Gulledge

Honors College

Genetic improvement of commercial lines has been a key component in the increased production of eastern oysters (Crassostrea virginica). One form of genetic improvement, induced triploidy, is commonly used to produce sterile oysters with faster growth and higher meat quality. However, the details of the physiological advantage provided by triploidy are poorly understood. Whole animal respiration is an important indicator of an individual’s capacity to meet increased energetic demands for growth and stress response. I have developed an assay for the Agilent’s XFe96 Extracellular Flux Analyzer to measure metabolic capacity (i.e., rates of basal, maximal, mitochondrial, and non-mitochondrial oxygen consumption) …

High And Low Toxin Producing Strains Of Karenia Brevis Differ Significantly In The Redox Proteome, Lipid Profiles, And Xanthophyll Cycle Pigments, Ricardo Colon

FIU Electronic Theses and Dissertations

The dinoflagellate Karenia brevis, blooms annually in the Gulf of Mexico, producing a suite of neurotoxins known as the brevetoxins. The cellular toxin content of K. brevis, however, is highly variable between or even within strains. I investigated biochemical differences between high (KbHT) and low (KbLT) toxin producing cultures both derived from the Wilson strain, related to energy-dependent quenching (qE) by photosystem II, and the content of reduced thiols of the proteome. By characterizing the xanthophyll content of the two strains I was able to determine that KbLT performs qE inconsistently. To investigate the …

Genetic Analysis Of Yellowtail (Seriola Lalandi) For Aquaculture In Maine, Sydney Avena

Honors College

Aquaculture is a growing industry in Maine, and identifying new species with potential for aquaculture is crucial for its continuing success. The University of Maine’s Center for Cooperative Aquaculture Research (CCAR) currently holds a stock of California yellowtail (Seriola lalandi). Similar in taste to tuna or mackerel, yellowtail are wild-caught as well as aquacultured in net pens and recirculating aquaculture systems worldwide. The fish presently at CCAR originally came from Great Bay Aquaculture and their genetic makeup is unknown. Recent research on S. lalandi suggests that this circumglobal fish has enough genetic difference between populations in the Northeast Pacific, Northwest …

A Brain-Infecting Parasite Impacts Host Metabolism Both During Exposure And After Infection Is Established, Lauren E. Nadler, Erik Bengston, Erika J. Eliason, Cameron Hassibi, Siri H. Helland-Riise, Ida B. Johansen, Garfield T. Kwan, Martin Tresguerres, Andrew V. Turner, Kelly L. Weinersmith, Øyvind Øverli, Ryan F. Hechinger

Marine & Environmental Sciences Faculty Datasets

1. Metabolic costs associated with parasites should not be limited to established infections. Even during initial exposure to questing and attacking parasites, hosts can enact behavioural and physiological responses that could also incur metabolic costs. However, few studies have measured these costs directly. Hence, little is known about metabolic costs arising from parasite exposure.
2. Further, no one has yet measured whether and how previous infection history modulates metabolic responses to parasite exposure.
3. Here, using the California killifish (Fundulus parvipinnis) and its brain-infecting parasite (Euhaplorchis californiensis), we quantified how killifish metabolism, behaviour, and osmoregulatory phenotype changed upon acute …

Evolutionary Expansions And Neofunctionalization Of Ionotropic Glutamate Receptors In Cnidaria, Ellen G. Dow

FIU Electronic Theses and Dissertations

Reef ecosystems are composed of a variety of organisms, transient species of fish and invertebrates, microscopic bacteria and viruses, and structural organisms that build the living foundation, coral. Sessile cnidarians, corals and anemones, interpret dynamic environments of organisms and abiotic factors through a molecular interface. Recognition of foreign molecules occurs through innate immunity via receptors identifying conserved molecular patterns. Similarly, chemosensory receptors monitor the environment through specific ligands. Chemosensory receptors include ionotropic glutamate receptors (iGluRs), transmembrane ion channels involved in chemical sensing and neural signal transduction. Recently, an iGluR homolog was implicated in cnidarian immunological resistance to recurrent infections of …

The Impact Of Invasive Lionfish On The Feeding Performance Of Endemic Spotted Scorpionfish, Nathaniel Zbasnik

Masters Theses & Specialist Projects

Invasive species, such as the red lionfish, Pterois volitans, are damaging many ecosystems around the world by out-competing native species. However, little work has been done to determine if P. volitans have a direct influence on the feeding performance of native species with which they compete. This study examines the feeding performance in terms of suction pressure, kinematic timing, and excursion distances of spotted scorpionfish, Scorpaena plumieri. Through multiple trials it was examined how S. plumieri modulate their kinematic behavior in response to P. volitans and a conspecific. The creation of a smaller buccal cavity and a decrease in time …

Blubber Transciptome Response To Acute Stress Axis Activation Involves Transient Charges In Adipogenesis And Lipolysis In Fast-Adapted Marine Mammal, J. I. Khudyakov, C. D. Champagne, L. M. Meneghetti, D. E. Crocker

Biological Sciences Faculty Publications

Stress can compromise an animal's ability to conserve metabolic stores and participate in energy-demanding activities that are critical for fitness. Understanding how wild animals, especially those already experiencing physiological extremes (e.g. fasting), regulate stress responses is critical for evaluating the impacts of anthropogenic disturbance on physiology and fitness, key challenges for conservation. However, studies of stress in wildlife are often limited to baseline endocrine measurements and few have investigated stress effects in fasting-adapted species. We examined downstream molecular consequences of hypothalamic-pituitary-adrenal (HPA) axis activation by exogenous adrenocorticotropic hormone (ACTH) in blubber of northern elephant seals due to the ease of …

Connecting The Physiological And Behavioral Response To Heat Stress On A Warming Planet, Anastasia Kalyta

Student Scholar Symposium Abstracts and Posters

Intertidal communities are considered good models of the biological effects of climate change on ecosystems, as their resident organisms are subjected to heat spells during daytime low tides. The increasing heat exposure can elicit behavioral as well as physiological responses in intertidal organisms. We studied the relationship between these responses to heat stress in the blue-banded hermit crab, Pagurus samuelis, by inducing a “heat shock” with elevated water temperature of 29 °C for 2.5 h. The behavioral effect of heat-shock was quantified using a 30-minute feeding assay, measuring the mass of a standard squid pellet consumed by individual hermit crabs. …

The Individual And Interactive Effects Of Nitrogen And Phosphorus Enrichment On Coral Reefs, Andrew A. Shantz

FIU Electronic Theses and Dissertations

Human domination of global nutrient cycles is profoundly altering our planet. Yet on coral reefs, the effects of changing nutrient regimes have likely been over-simplified. This dissertation investigates the complexity of animal-nutrient interactions at the organismal level and explores how the outcomes of these interactions cascade through levels of biological organization. To do so, I examined the effects of nitrogen (N) and phosphorus (P) on corals and macroalgae, and how these effects in turn influenced reef communities and entire ecosystems. I show that P consistently increases coral growth rates while N has variable, often negative, effects on coral growth. The …

Long-Term, High Frequency In Situ Measurements Of Intertidal Mussel Bed Temperatures Using Biomimetic Sensors, Brian Helmuth, Francis Choi, Allison Matzelle, Jessica Torossian, Scott Morello, K.A.S. Mislan, Lauren Yamane, Denise Strickland, P. Szathmary, Sarah Gilman, Alyson Tockstein, Thomas Hilbish, Michael Burrows, Anne Marie Power, Elizabeth Gosling, Nova Mieszkowska, Christopher Harley, Michael Nishizaki, Emily Carrington, Bruce Menge, Laura Petes, Melissa Foley, Angela Johnson, Megan Poole, Mae Noble, Erin Richmond, Matt Robart, Jonathan Robinson, Jerod Sapp, Jackie Sones, Bernardo Broitman, Mark Denny, Katharine Mach, Luke P. Miller, Michael O'Donnell, Philip Ross, Gretchen Hofmann, Mackenzie Zippay, Carol Blanchette, J. Macfarlan, Eugenio Carpizo-Ituarte, Benjamin Ruttenberg, Carlos Peña Mejía, Christopher Mcquaid, Justin Lathlean, Cristián Monaco, Katy Nicastro, Gerardo Zardi

Faculty Publications, Biological Sciences

At a proximal level, the physiological impacts of global climate change on ectothermic organisms are manifest as changes in body temperatures. Especially for plants and animals exposed to direct solar radiation, body temperatures can be substantially different from air temperatures. We deployed biomimetic sensors that approximate the thermal characteristics of intertidal mussels at 71 sites worldwide, from 1998-present. Loggers recorded temperatures at 10–30 min intervals nearly continuously at multiple intertidal elevations. Comparisons against direct measurements of mussel tissue temperature indicated errors of ~2.0–2.5 °C, during daily fluctuations that often exceeded 15°–20 °C. Geographic patterns in thermal stress based on biomimetic …

Sea Turtle Hatchling Sex Ratios Determined Via Hormone Assay: Implications Of Climate Change?, William A. Hilton, Matthew Godfrey, Camryn D. Allen

STAR Program Research Presentations

Currently all species of sea turtles are listed as threatened or endangered with extinction under the U.S. Endangered Species Act. Due to their status, sea turtle conservation is a high priority for the U.S. National Marine Fisheries Service and U.S. Fish and Wildlife Service. One major challenge conservationists face is the lack of a noninvasive, cost efficient method for determining the sex of hatchling sea turtles. Because secondary sex characteristics (i.e. males have longer tails) are not evident until turtles start to reach sexual maturity, the sex of hatchlings is not easily determined. The least invasive way to determine the …

Acute Toxicity Assessment Of N,N-Diethyl-M-Toluamide (Deet) On The Photosynthetic Activity Of The Dinoflagellate Gymnodinium Instriatum, Eloy Martinez, Sylvia Velez, Marietta Mayo, Miguel Sastre

Faculty Research & Creative Activity

Despite the ubiquitous occurrence of N, N-diethyl-m-toluamide (DEET) in aquatic systems, assessments evaluating the toxicity of DEET on phytoplankton species are summed to a single study on a unicellular green alga. In particular, the toxicological effects of DEET in dinoflagellates are unknown. In this study, we employed the mixotrophic dinoflagellate Gymnodinium instriatum as a study system to evaluate acute effects of DEET on the oxygen flux of laboratory cultures. This study reports an inhibitory reaction model of DEET described by the equation y = 4.99 x 0.54, where y represents the percent inhibition of oxygen flux and x represents DEET …

Physiological Performance Of Warm-Adapted Marine Ectotherms: Thermal Limits Of Mitochondrial Energy Transduction Efficiency, Eloy Martinez, Eric Hendricks, Michael Menze, Joseph Torres

Faculty Research & Creative Activity

Thermal regimes in aquatic systems have profound implications for the physiology of ectotherms. In particular, the effect of elevated temperatures on mitochondrial energy transduction (i.e. energy from carbon substrates to ATP) in tropical and subtropical teleosts may have profound consequences on organismal performance and population viability. Upper and lower whole-organism critical temperatures for teleosts suggest that subtropical and tropical species are not susceptible to the warming trends associated with climate change, but sub-lethal effects on energy transduction efficiency and population dynamics remain unclear. The goal of the present study was to compare the thermal sensitivity of processes associated with mitochondrial …

Melanin As An Oto-Protective Pigment In Two Fish Species: Poecilia Latipinna And Cyprinus Carpio , Bethany N. Coffey

Masters Theses & Specialist Projects

Melanin is the dark pigment found in most organisms that gives color to the skin, hair, feathers, and eyes of vertebrates. While melanin is known to also be present in the stria vascularis of the mammalian cochlea, its function in the inner ear is still unknown. Some previous studies have indicated that melanin may serve to protect the mammalian ear from hearing loss. Minimal previous research on melanin within the inner ears of fishes has been conducted. In this study, the melanin levels in the inner ears of different color morphs of two fish species (Poecilia latipinna and Cyprinus …

Acclimatization Of The Tropical Reef Coral Acropora Millepora To Hyperthermal Stress, Anthony John Bellantuono

FIU Electronic Theses and Dissertations

The demise of reef-building corals potentially lies on the horizon, given ongoing climate change amid other anthropogenic environmental stressors. If corals cannot acclimatize or adapt to changing conditions, dramatic declines in the extent and health of the living reefs are expected within the next half century. The primary and proximal global threat to corals is climate change. Reef-building corals are dependent upon a nutritional symbiosis with photosynthetic dinoflagellates belonging to the group Symbiodinium. The symbiosis between the cnidarian host and algal partner is a stress-sensitive relationship; temperatures just 1°C above normal thermal maxima can result in the breakdown of …

Interspecific Variation In Palatability Suggests Cospecialization Of Antipredator Defenses In Sea Hares, Kimberly K. Takagi, Nadia N. Ono, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Prey species often deploy different kinds of antipredator defenses, which can interact with each other in ways that are not yet completely understood. Much research into these interactions has utilized gastropod mollusks, usually focusing (in part) on the protective utility of the gastropod shell. This makes the evolutionary reduction of the shell in the opisthobranch gastropods (marine slugs) particularly interesting. This loss of protective function of the shell is associated with the evolution of alternative defenses. Particularly well studied are chemical defenses, especially those using secondary metabolites derived from food resources. As a first step toward understanding interspecific variation in …

Characterization Of 35 Microsatellite Loci In The Pacific Lion-Paw Scallop (Nodipecten Subnodosus) And Their Cross-Species Amplification In Four Other Scallops Of The Pectinidae Family, Ana M. Ibarra, Jessica Lynn Petersen, Thomas R. Famula, Bernie May

Department of Animal Science: Faculty Publications

Four microsatellite-enriched DNA libraries yielded 35 microsatellite loci from 100 primer pairs designed for Pacific lion-paw scallop, Nodipecten subnodosus. The number of alleles ranged from four to 28. Three of the 35 loci were not in Hardy–Weinberg equilibrium and linkage disequilibrium was found for one pair of loci. These microsatellites will be used to analyze the population structure of the species in Mexico’s Baja Peninsula to propose management strategies for scallop aquaculture development. Twenty-six primer pairs cross-amplified in Nodipecten nodosus, whereas none (Argopecten ventricosus) or few cross-amplified in the Argopecten species.

Is Hemoglobin Gelation An Adaptation To The Cold In Boreal Fishes?, Ione Hunt Von Herbing

University of Maine Office of Research Administration: Grant Reports

Recent studies of fish red blood cells found that a regular paracrystalline array of hemoglobin (Hb) tetamers formed under low oxygen conditions in 2 species of boreal fishes, Atlantic cod (Gadus morhua) and toadfish, (Opsanus tau). This phenomenon is termed hemoglobin gelation and its physiological characteristics and importance to survival of boreal fishes is unknown. The study outlined in this proposal will obtain preliminary data on the frequency and physiological nature of the phenomenon of hemoglobin (Hb) gelation in red blood cells of fishes that inhabit cold-water temperate and Arctic environments. The present study will test the hypothesis that hemoglobin …

Critical Flicker Frequency In A Harp Seal, Pagophilus Groenlandicus (Erxleben, 1777), Charles D. Bernholz

UNL Libraries: Faculty Publications

Critical flicker frequency (CFF) in a free-swimming harp seal (Pagophilus groenlandicus) was investigated using behavioral techniques. The resulting CFF versus intensity contour indicates a definite rod-cone break, confirming a duplex photoreceptor population whose presence had not been observed in previous morphological reports.