Research Projects

Produce, clone, and cryopreserve, immortal rmurine hybridomos secreting IgG class monoclonal antibodies (MAB) which bind to P marinus cell walls and soluble proteins. Test binding specificities of MABs for P marinus using fluorescence immunoessays of various histological samples containing diverse Perkinsus sp. pathogens, and other possible related protozoans. Optimize MAB utilities as ELISA assay reagents, evaluate clinical performance of MAB diagnostic ELISA assay, and localize subcellular MAB binding epitopes.

Construct 24 mound oyster shell reefs planted with hatchery-produced spat on or near the Flag Pond oyster bar. Monitor water quality in and around the reef habitats, characterize differences between water qualities at the different depths. Sample oysters to determine relationships between anoxia, P. marinus prevalence and weighted prevalence (intensity), and physiological state of the oysters. Measure the physiological response of oysters to hypoxia in the benthos using real-time water quality measurement and diver sampling during the episode(s). Correlate physiological changes in the oysters with position on the reef habitat, depth, and disease acquisition and progression.

To evaluate, design, and implement a system to network distributed data bases of environmental data sets located at the nations marine labs to provide visual displays on spatial and temporal scales for research, management and educational use.

The objective of the proposed research is to use surface observations of ocean color on buoys to calibrate and validate satellite-derived products from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). Ocean color sensors will be deployed on buoys of the Chesapeake Bay Observing System (CBOS) in the mid - to lower Bay and coordinated with aircraft and satellite measurements.

To use the estimated model to assess changes in behavior, conditioned on land use, as well as actual changes in land use patterns under an array of alternative policy scenarios that are likely ultimately to have significant effects on water quality. 2. The consequences for non-point source pollution of the predicted land use changes can be assessed by feeding the results of the spatially articulated economics (human activity) model into any similarly conceived spatial model of the ecosystem.

To study the biological activity of the novel GnRH in striped bass and to design and select super-active analogs of this peptide to be used for improved spawning induction therapies in striped bass and other farmed fish. To study the regulation of the synthesis and release of the novel GnRH in striped bass, in order to understand the nature of the hormonal failure that results in the lack of ovulation and spawning in captive striped bass and other farmed marine fish. Improve the technology for spawning induction in striped bass, based on the administration of super-active analogs of the most physiologically relevant sbGnRH, or of the most potent cGnRH-II, at the appropriate dose, pattern and timing.

To develop collaborations and partnerships that help UMES to strengthen its Sea Grant related teaching and research programs. Sea Grant funded scientists would be assisting UMES in providing extremely high quality education for our students, thus providing the nation with minorities who have acquired expertise in the marine sciences.

The goals of this proposed research are to understand the permeability of teleost embryos to water and cryoprotectants in order to develop an uncomplicated, low-cost germ plasm cryopreservation system that may be applicable to many fish species. Traditional cryobiological techniques have been unsuccessful in developing successful approaches because they revealed little about the permeability of the embryos (a crucial element for successful cryopreservation). In order to increase our understanding of permeability, we will use magnetic resonance (MR) microscopy on zebrafish embryos.

We will test the hypothesis that water quality in eutrophic estuaries can be substantially improved as a consequence of the feeding activity of bivalves. These organisms serve to remove large quantities of phytoplankton and hence may reduce the amount of organic material settling beneath the estuarine pycnocline where its degradation causes hypoxia. We will determine if the rate and form of nitrogen regenerated from oyster biodeposits in aerobic waters differs from when the same amount of plankton biomass is degraded through anaerobic microbial processes. This research is pertinent to both the Environmental Studies and Fisheries and Aquaculture programmatic areas.

Our objective is to determine the mechanism by which Perkinsus marinus acquires iron from its host and how available iron controls the gene expression in the parasite, particularly in those aspects related to its proliferation and intracellular survival. Free or protein-bound iron is an essential factor for many apicomplexan parasites and for most eukaryotic cells in culture. P. marinus proliferation rates in vitro are highly dependent on available iron. The degree of concentration of metals such as iron, in the oyster host Crassostrea virginica is related to environmental factors. It is possible that, in the case of P. marinus and C.

To evaluate several biotechnology approaches for producing biologically active recombinant red drum growth hormone (GH), to understand the physiology of GH secretion and the possible functions of GH in red drum, and to determine whether feeding the recombinant hormone in the diet is an effective method for administering GH and promoting growth of fish. Long-term goals are to develop techniques for mass producing piscine recombinant growth hormones inexpensively, to undertake a comprehensive investigation of the functions of GH using the recombinant hormone, as well as developing a practical method for administering them to fish at commercial aquaculture facilities to enhance fish growth.

Identify the transmissible agent, presumably a ciliated protist, responsible for JOD in North Eastern United States. Establish the etiology and identity of the disease pathogen. Culture the transmissible agent, presumably a ciliated protist, in suitable media. Transmit the presumed pathogenic ciliate to cultured parasite free oysters and recover the parasite after the oysters have come down with the infection. Detection of the JOD organism in other species of cultured oysters and identify such a ciliate pathogen if one is found.

Chitosan is a promising renewable resource which can be used for a range of applications, yet it remains underutilized. Recently we developed an enzyme strategy to specifically functionalize chitosan under environmentally-friendly conditions. To demonstrate the commercial potential of this enzymatically-modified chitosan, we propose to characterize the capabilities and limitations of the functionalization procedures, and then to study how functionalization can be used to controllably alter technologically-important chemical, mechanical and biological properties. To facilitate transfer of this technology from the university to commercial practice, we have been and will continue working closely with our industrial partner.

The overall objective is to determine if b-glucan will continue to exert a immunostimulating (protective) activity against pathogenic bacterial infection in striped bass in the face of aquaculture-associated stress. A positive finding would indicate that this agent has good potential for disease protection, both as a broad-spectrum immune stimulator and by increasing the potency of bacterial vaccines.

Our research program is directed at understanding the host-parasite interaction that exists between the eastern oyster C. virginica and the protozoan parasite P. marinus ("Dermo") by identifying genetic and molecular events that are critical for P. marinus, host specificity, hemocyte entry, intracellular survival and proliferation. Our progress to date has: described the inhibitory effect of iron chelators on P. marinus' growth rates; demonstrated a stimulation of growth rates in the presence of exogenous glycoproteins; and established the optimal conditions for P. marinus culture. We plan to develop molecular strategies targeted to blocking host recognition mechanisms, and the parasite's ability to enter and successfully replicate and proliferate throughout the body of its host.

To investigate the bioconcentration of Hg and methyl Hg in organisms representative of the Chesapeake Bay from both pelagic and benthic food chains. To ascertain relative assimilation efficiencies of inorganic and methyl Hg by algae (pelagic/benthic diatoms or dinoflagellates) and by zooplankton and zoobenthos. To elucidate water column variables and sediment chemistry controlling uptake by microorganisms and factors controlling assimilation by zooplankton/zoobenthos. To assess transfer of Hg and methyl Hg between primary consumers and fish.

The objective of the proposed research is to use ocean color data from aircraft remote sensing to determine the distribution of chlorophyll in Chesapeake Bay. We will use a combination of the data from aircraft overflights with two instruments, the Ocean Data Acquisition System (ODAS) and the SeaWiFS Aircraft Simulator (SAS II), with those from Shipboard and satellite studies to assess the relationship of principal forcing functions in the Bay to seasonal and interannual variations in phytoplankton abundance. A series of 25-30 flights is proposed for 1996. Spanning late February through October. This project represents a continuation of the regional remote sensing program we have developed in recent years.

Since 1962 the Haskin Shellfish Research Laboratory has been selectively breeding eastern oysters (Crassostrea virginica) for resistance to the parasite Haplosporidium nelsoni that causes MSX-disease. MSX-disease resistance was obtained relatively (over several generations) and pedigreed lines are still maintained. Since 1992 synthetic lines developed from controlled matings of these same pedigreed lines, were begun in response to Dermo disease pressure. With the collaboration of four mid-Atlantic institutions, the objective of this project is to institute a regional selective breeding program for developing oyster stocks resistant to MSX and Dermo disease.

Develop, calibrate, and validate a Haplosporidium nelsoni submodel, to be linked to an existing Crassostrea virginica-Perkinsus marinus host-parasite population dynamics model. Assemble and quality-assure calibration and input data from Chesapeake Bay Oyster population and disease monitoring programs. Develop spatial grid interpolations to match environmental and biological data for the Chesapeake Bay. Perform site-specific model runs for selected Virginia and Maryland sites, and for 64 Maryland Modified Fall Oyster Survey sites, the latter runs to be used for statistical tests of model performance. Apply a recently developed dual disease oyster model to high priority oyster management issues.

This project examines the meaning of restoration in the Chesapeake Bay by exploring the human relationships with the Bay that have been threatened or disrupted by industrial and commercial development. Utilizing the concept of "place," it will provide framework for understanding restoration in cultural and psychological, as well as biological and economic terms. The project will elicit contemporary visions of restoration through focus groups comprised of Bay area residents, workers, users, activists, and policy makers, and will investigate historical and literary accounts of the Bay to place contemporary views in a broader context.

Collect fry or fingerlings from five different strains of striped bass and rear to a suitable size for tank culture. Compare between and among production performance of the different strains for 24 months in a recirculating and flow-through system. Track performance on a monthly basis of each separate strain and family. Compare growth, survival, FCR, and dress-out percentages of the five strains and families in the different systems. Determine the fastest growing, best adapted strain for between-family selection potential.

To identify genetic differences among geographically separate C. virginica populations. To correlate genetic differences or markers among those populations with differences in disease susceptibility or resistance.

We plan to apply the methodologies developed from our current NMFS-funded project for mtDNA markers, DNA fingerprinting, RNA probes and PCR technologies to quantify low-levels of Perkinsus marinus infections in order to fully describe the etiology of this oyster disease. Our progress in working with genetic markers of P. marinus has: Developed a sensitive PCR-based diagnostic assay for detecting P. marinus infections ; Identified an extrachromosomal relic plastid-genome in P. marinus that is indicative of this species' close affinity to dinoflagellates and a photosynthetic ancestor; Described two ribosomal RNA genes that have been used in a phylogenetic reconstruction of the ancestral lineages of P. marinus ; Quantified tissue-specific P.

To implement the most successful of several recent wind-wave computer models (currently being tested in a limited region of upper Chesapeake Bay) for the entire Bay; to gather a suite of wind and wave observations in northern Chesapeake Bay during different seasons and at different locations, both for the intrinsic value of the wave data and for comparison to and calibration of the model(s); to generate a model data base of general wave climatology and predicted responses to specific events; to develop a graphically oriented data base front end for other interested scientists and managers, in order to allow them to explore the surface wave climate of the northern Bay without having to implement or run the wave model.

The overall objective of the proposed research is to understand the endocrine mechanism regulating the onset of puberty in fish, using striped bass as a model, with a view towards developing techniques for accelerating or inhibiting puberty in farmed fish. This objective will be obtained through the following steps: study the ontogeny of the brain-pituitary gonadal (BPG) function prior to and throughout puberty study the ontogeny of the responsiveness of BPG axis to exogenous hormones induction of advanced (precocious) complete gametogenesis leading to spawning of good-quality eggs.