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Comparative Accumulation And Effects Of Microplastics And Microplastic-Associated Pcb-153 In The White Hard Clam (Meretrix Lyrata) And Giant River Prawn (Macrobrachium Rosenbergii) Following Chronic Exposure, Bao-Son Trinh, Lien Thi Le, Loc Minh Tran, Gunther Rosen, Robert C. Hale May 2024

Comparative Accumulation And Effects Of Microplastics And Microplastic-Associated Pcb-153 In The White Hard Clam (Meretrix Lyrata) And Giant River Prawn (Macrobrachium Rosenbergii) Following Chronic Exposure, Bao-Son Trinh, Lien Thi Le, Loc Minh Tran, Gunther Rosen, Robert C. Hale

VIMS Articles

Global environmental abundance of microplastics (MPs) is increasing. MPs may sorb hydrophobic organic contaminants (HOCs), accumulate in and cause deleterious effects on exposed organisms. This study investigated and compared the accumulation and effects of MPs and MP-associated PCB in the two indigenous aquatic organisms in Viet Nam, the white hard clams, Meretrix lyrata, and the giant river prawns, Macrobrachium rosenbergii. The test organisms were exposed to either polyethylene microbeads (PEMBs), waterborne polychlorinated biphenyl 153 (PCB-153), or PEMB-associated PCB-153 (PEMB-PCB) over 28 days. Organismal MP accumulation, survival, and weight gain were examined at various sampling intervals. In general, MP …


Dietary Shifts And The Need For Increased Sustainability Approaches In The Global Aquaculture Seafood System, Darien D. Mizuta Feb 2024

Dietary Shifts And The Need For Increased Sustainability Approaches In The Global Aquaculture Seafood System, Darien D. Mizuta

VIMS Articles

Recent shifts in the global dietary preferences have indicated the fast-growing choice for plant-based, or meat-reduced diets. Among the motivations for such choices, which are increasingly advocated by nations and environmental institutions, is the major concern with global environmental sustainability and impacts of food production systems. Incontestably, the animal food source industry is extremely diverse, and seafood production through the aquaculture value chain remains unfamiliar to key stakeholders possibly leading to an uncomprehensive view and often biased perception of the farming industry within the environmental context. Accordingly, I discuss the importance of seafood production systems, such as the fastest seafood …


Detection Of Toxins And Harmful Algal Bloom Cells In Shellfish Hatcheries And Efforts Toward Removal, Marta P. Sanderson, Karen Hudson, Lauren Gregg, Amanda Chesler-Poole, Ja M. Small, Kimberly S. Reece, Ryan Carnegie, Juliette L. Smith Jan 2023

Detection Of Toxins And Harmful Algal Bloom Cells In Shellfish Hatcheries And Efforts Toward Removal, Marta P. Sanderson, Karen Hudson, Lauren Gregg, Amanda Chesler-Poole, Ja M. Small, Kimberly S. Reece, Ryan Carnegie, Juliette L. Smith

VIMS Articles

As the start of the supply chain for the aquaculture industry, hatcheries are a crucial component in the success of oyster and northern quahog (hard clam) aquaculture on the East Coast of the US. Intermittent failures in hatchery production slow industry growth and reduce profits. To begin investigations into the possible role of algal toxins in hatchery production failure, post-treatment hatchery water from one research and four commercial hatcheries in lower Chesapeake Bay, USA, was sampled for (1) toxin presence and (2) harmful algal bloom (HAB) cell enumeration. Overall, seven toxin classes, likely produced by six different HAB species, were …


Vibrio Vulnificus And Vibrio Parahaemolyticus In Oysters Under Low Tidal Range Conditions: Is Seawater Analysis Useful For Risk Assessment?, Corinne Audemard, Tal Ben-Horin, Howard I. Kator, Kimberly S. Reece Jan 2022

Vibrio Vulnificus And Vibrio Parahaemolyticus In Oysters Under Low Tidal Range Conditions: Is Seawater Analysis Useful For Risk Assessment?, Corinne Audemard, Tal Ben-Horin, Howard I. Kator, Kimberly S. Reece

VIMS Articles

Human-pathogenic Vibrio bacteria are acquired by oysters through filtering seawater, however, the relationships between levels of these bacteria in measured in oysters and overlying waters are inconsistent across regions. The reasons for these discrepancies are unclear hindering our ability to assess if -or when- seawater samples can be used as a proxy for oysters to assess risk. We investigated whether concentrations of total and human pathogenic Vibrio vulnificus (vvhA and pilF genes) and Vibrio parahaemolyticus (tlh, tdh and trh genes) measured in seawater reflect concentrations of these bacteria in oysters (Crassostrea virginica) cultured within the US lower Chesapeake Bay region. …


A Deterministic Model For Understanding Nonlinear Viral Dynamics In Oysters, Qubin Qin, Jian Shen, Kimberly S. Reece Jan 2022

A Deterministic Model For Understanding Nonlinear Viral Dynamics In Oysters, Qubin Qin, Jian Shen, Kimberly S. Reece

VIMS Articles

Contamination of oysters with a variety of viruses is one key pathway to trigger outbreaks of massive oyster mortality as well as human illnesses, including gastroenteritis and hepatitis. Much effort has gone into examining the fate of viruses in contaminated oysters, yet the current state of knowledge of nonlinear virus-oyster interactions is not comprehensive because most studies have focused on a limited number of processes under a narrow range of experimental conditions. A framework is needed for describing the complex nonlinear virus-oyster interactions. Here, we introduce a mathematical model that includes key processes for viral dynamics in oysters, such as …


Penaeid Shrimp In Chesapeake Bay: Population Growth And Black Gill Disease Syndrome, Troy D. Tuckey, Jillian L. Swinford, Mary C. Fabrizio, Hamish J. Small, Jeffrey D. Shields Jan 2021

Penaeid Shrimp In Chesapeake Bay: Population Growth And Black Gill Disease Syndrome, Troy D. Tuckey, Jillian L. Swinford, Mary C. Fabrizio, Hamish J. Small, Jeffrey D. Shields

VIMS Articles

Since 1991, the number of penaeid shrimp occurring in Virginia waters of Chesapeake Bay has steadily increased, prompting an interest in developing a fishery. Although development of a shrimp fishery in the Chesapeake Bay region could bring economic benefits, the fishery may be hampered by the presence of a disease syndrome known as shrimp black gill (sBG). The objectives of our study were to (1) describe the spatial distribution and abundance patterns of shrimp in Chesapeake Bay, (2) relate relative abundance of shrimp to habitat characteristics, and (3) determine the presence and seasonality of sBG to better understand disease dynamics …


Sperm Repository For A Breeding Program Of The Eastern Oyster Crassostrea Virginica: Sample Collection, Processing, Cryopreservation, And Data Management Plan, H. Yang, Y. Huo, J. C. Yee, S. Rickard, W. C. Walton, E. Saillant Jan 2021

Sperm Repository For A Breeding Program Of The Eastern Oyster Crassostrea Virginica: Sample Collection, Processing, Cryopreservation, And Data Management Plan, H. Yang, Y. Huo, J. C. Yee, S. Rickard, W. C. Walton, E. Saillant

VIMS Articles

The Eastern oyster Crassostrea virginica (Family Ostreidae) is one of the most important fishery and aquaculture species in the U.S. and is a keystone species for coastal reefs. A breeding program was initiated in 2019 to support the fast‐growing aquaculture industry culturing this species in the Gulf of Mexico. Oysters from 17 wild populations in embayment along the U.S. Gulf of Mexico coast from southwest Florida to the Matagorda Bay, Texas were used as broodstock for the program to maximize genetic diversity in the base population. A sperm repository of the broodstock was established to support the breeding project. The …


Aquaculture Reuse Water, Genetic Line, And Vaccination Affect Rainbow Trout (Oncorhynchus Mykiss) Disease Susceptibility And Infection Dynamics, Jeremy L. Everson, Darbi R. Jones, Amy K. Taylor, Barbara J. Rutan, Timothy D. Leeds, Kate E. Langwig, Andrew R. Wargo, Gregory D. Wiens Jan 2021

Aquaculture Reuse Water, Genetic Line, And Vaccination Affect Rainbow Trout (Oncorhynchus Mykiss) Disease Susceptibility And Infection Dynamics, Jeremy L. Everson, Darbi R. Jones, Amy K. Taylor, Barbara J. Rutan, Timothy D. Leeds, Kate E. Langwig, Andrew R. Wargo, Gregory D. Wiens

VIMS Articles

Infectious hematopoietic necrosis virus (IHNV) and Flavobacterium psychrophilum are major pathogens of farmed rainbow trout. Improved control strategies are desired but the influence of on-farm environmental factors that lead to disease outbreaks remain poorly understood. Water reuse is an important environmental factor affecting disease. Prior studies have established a replicated outdoor-tank system capable of varying the exposure to reuse water by controlling water flow from commercial trout production raceways. The goal of this research was to evaluate the effect of constant or pulsed reuse water exposure on survival, pathogen prevalence, and pathogen load. Herein, we compared two commercial lines of …


Morphological And Mitochondrial Dna Analyses Of Oysters In The Northern Bay Of Bengal, Bangladesh, Mohammed S. N. Chowdhury, Kimberly S. Reece, Sourav S. Joy, Loren D. Coen, Aad C. Smaal Jan 2021

Morphological And Mitochondrial Dna Analyses Of Oysters In The Northern Bay Of Bengal, Bangladesh, Mohammed S. N. Chowdhury, Kimberly S. Reece, Sourav S. Joy, Loren D. Coen, Aad C. Smaal

VIMS Articles

The geographic boundaries of many important habitat-building shallow estuarine oyster (Family Ostreidae) species are poorly understood, especially in subtropical and tropical waters. These keystone species often have extensive historical and extant ranges, in part because of their ability to adapt to diverse environmental conditions and the transfer and introduction of a few species worldwide for aquaculture production. In addition, oysters exhibit morphological plasticity additionally confounding species identification and taxonomy. Molecular techniques have led to significant improvements in oyster systematics and taxonomy but have not been applied to oysters from many tropical regions, including the coastal areas of the Indian Ocean …


Current And Future Remote Sensing Of Harmful Algal Blooms In The Chesapeake Bay To Support The Shellfish Industry, Jl Wolny, Mc Tomlinson, S Schollaert Uz, Ta Egerton, Jr Mckay, A Meredith, Ks Reece, Gp Scott, Rp Stumpf May 2020

Current And Future Remote Sensing Of Harmful Algal Blooms In The Chesapeake Bay To Support The Shellfish Industry, Jl Wolny, Mc Tomlinson, S Schollaert Uz, Ta Egerton, Jr Mckay, A Meredith, Ks Reece, Gp Scott, Rp Stumpf

VIMS Articles

Harmful algal bloom (HAB) species in the Chesapeake Bay can negatively impact fish, shellfish, and human health via the production of toxins and the degradation of water quality. Due to the deleterious effects of HAB species on economically and environmentally important resources, such as oyster reef systems, Bay area resource managers are seeking ways to monitor HABs and water quality at large spatial and fine temporal scales. The use of satellite ocean color imagery has proven to be a beneficial tool for resource management in other locations around the world where high-biomass, nearly monospecific HABs occur. However, remotely monitoring HABs …


Acute And Long-Term Manganese Exposure And Subsequent Accumulation In Relation To Idiopathic Blindness In The American Lobster, Homarus Americanus, Addison T. Ochs, Jeffrey D. Shields, Gary W. Rice, Michael A. Unger Feb 2020

Acute And Long-Term Manganese Exposure And Subsequent Accumulation In Relation To Idiopathic Blindness In The American Lobster, Homarus Americanus, Addison T. Ochs, Jeffrey D. Shields, Gary W. Rice, Michael A. Unger

VIMS Articles

Manganese (Mn) is a hypoxic reactive metal commonly found in marine sediments. Under hypoxic conditions the metal becomes fully reduced to Mn2+ and is biologically available to the benthic community for uptake. Mn is also a potent neurotoxin and it may play a role in the etiology of idiopathic blindness that has been observed in American lobsters. An acute exposure study was designed to expose American lobster, Homarus americanus, to 0, 20, 80, 150, and 300 mg L−1 (ppm) for 96 hs to explore disparities in Mn accumulation among several tissues: optic nerve, brain, hepatopancreas, muscle, hemolymph, …


Population Structure Of The Blue Crab Callinectes Sapidus In The Maryland Coastal Bays, Kristen A. Lycett, Jeffrey D. Shields, J. Sook Chung, Joseph S. Pitula Jan 2020

Population Structure Of The Blue Crab Callinectes Sapidus In The Maryland Coastal Bays, Kristen A. Lycett, Jeffrey D. Shields, J. Sook Chung, Joseph S. Pitula

VIMS Articles

The population structure of the blue crab Callinectes sapidus was examined in the Maryland Coastal Bays (MCB) from 2014 to 2016. Crabs were sampled from April to December of each year. Size–frequency distributions showed a strong seasonal cycle, with small crabs being abundant in April, increasing in size through September, with adult crabs observed in the highest proportions from August through October of each year. A subsample of crabs was assayed for hemolymph ecdysone concentrations to examine molting patterns in field-collected blue crabs. Molting was observed throughout the sampling season, peaking in April for immature crabs, with lows in all …


Quantifying The Behavioral And Economic Effects Of Regulatory Change In A Recreational Cobia Fishery, Andrew M. Scheld, William M. Goldsmith, Shelby White, Hamish J. Small, Susanna Musick Jan 2020

Quantifying The Behavioral And Economic Effects Of Regulatory Change In A Recreational Cobia Fishery, Andrew M. Scheld, William M. Goldsmith, Shelby White, Hamish J. Small, Susanna Musick

VIMS Articles

Fisheries economists typically assume recreational anglers make decisions that maximize individual angler utility, which may depend on fishery and regulatory conditions. Under this framework, changes in regulations can lead to target species substitution by anglers in response to shifts in expectations of trip utility. A stated preference survey was developed and distributed to recreational cobia (Rachycentron canadum) anglers in Virginia to explore the effects of regulatory change on angler decision-making, species targeting, and resulting economic outcomes. The survey included a series of hypothetical choice scenarios, where respondents were asked to select their most preferred alternative after being presented with different …


Characterization Of Microsporidian Ameson Herrnkindi Sp. Nov. Infecting Caribbean Spiny Lobsters Panulirus Argus, Hamish J. Small, Gd Stentiford, Dc Behringer, Ma Freeman, Nam Atherley, Kimberly S. Reece, Jeffrey D. Shields Oct 2019

Characterization Of Microsporidian Ameson Herrnkindi Sp. Nov. Infecting Caribbean Spiny Lobsters Panulirus Argus, Hamish J. Small, Gd Stentiford, Dc Behringer, Ma Freeman, Nam Atherley, Kimberly S. Reece, Jeffrey D. Shields

VIMS Articles

The Caribbean spiny lobster Panulirus argus supports a large and valuable fishery in the Caribbean Sea. In 2007-2008, a rare microsporidian parasite with spore characteristics typical of the Ameson genus was detected in 2 spiny lobsters from southeast Florida (FL). However, the parasite species was not confirmed by molecular analyses. To address this deficiency, reported here are structural and molecular data on single lobsters displaying comparable ‘cotton-like’ abdominal muscle containing ovoid microsporidian spores found at different locations in FL in 2014 and 2018 and in Saint Kitts and Nevis Islands in 2017. In the lobster from 2014, multiple life stages …


Multiple Drivers Of Interannual Oyster Settlement And Recruitment In The Lower Chesapeake Bay, Brendan Turley, Kimberly S. Reece, Jian Shen, Jeong-Ho Lee, Ximing Guo, Jan Mcdowell May 2019

Multiple Drivers Of Interannual Oyster Settlement And Recruitment In The Lower Chesapeake Bay, Brendan Turley, Kimberly S. Reece, Jian Shen, Jeong-Ho Lee, Ximing Guo, Jan Mcdowell

VIMS Articles

Despite global investment in shellfish restoration activities, relatively little attention has been given to predicting optimal restoration sites and testing these expectations. We used a coupled biological-physical connectivity model as a guide to plant two distinct hatchery-spawned strains of the eastern oyster, Crassostrea virginica, in the Lafayette River, Virginia during the summer of 2013 at two locations corresponding to virtual spawning locations within the connectivity model. We utilized single nucleotide polymorphism markers to test the model predictions by genotyping oysters recruited after planting two hatchery-spawned strains and examining interannual recruitment variability for two successive years. Two spat were identified …


Tracking Triploid Mortalities Of Eastern Oysters Crassostrea Virginica In The Virginia Portion Of The Chesapeake Bay, Eric Guevelou, Ryan Carnegie, Ja Moss, Karen Hudson, Kimberly S. Reece, Molly M. Rybovich, Standish K. Allen Jr. Jan 2019

Tracking Triploid Mortalities Of Eastern Oysters Crassostrea Virginica In The Virginia Portion Of The Chesapeake Bay, Eric Guevelou, Ryan Carnegie, Ja Moss, Karen Hudson, Kimberly S. Reece, Molly M. Rybovich, Standish K. Allen Jr.

VIMS Articles

Since 2012, aquacultured eastern oysters Crassostrea virginica have been reported by oyster farmers to display mortality approaching 30%, and in some cases 85%, in areas of the lower Chesapeake Bay, VA. Based on accounts from industry, this mortality has typically affected 1-y-old oysters between May and early July, and has tended to occur in triploid oysters, which represent the vast bulk of production in the area. During this period, samples submitted for pathology have not revealed the presence of major pathogens as a cause. In 2015, to gain deeper insight into this mortality and determine whether specific sites, ploidy condition, …


Climate Change Enhances Disease Processes In Crustaceans: Case Studies In Lobsters, Crabs, And Shrimps, Jeffrey D. Shields Jan 2019

Climate Change Enhances Disease Processes In Crustaceans: Case Studies In Lobsters, Crabs, And Shrimps, Jeffrey D. Shields

VIMS Articles

Climate change has resulted in increasing temperature and acidification in marine systems. Rising temperature and acidification act as stressors that negatively affect host barriers to infection, thus enhancing disease processes and influencing the emergence of pathogens in ecologically and commercially important species. Given that crustaceans are ectotherms, changes in temperature dominate their physiological and immunological responses to microbial pathogens and parasites. Because of this, the thermal ranges of several crustacean hosts and their pathogens can be used to project the outcomes of infections. Host factors such as molting, maturation, respiration, and immune function are strongly influenced by temperature, which in …


Intensive Oyster Aquaculture Can Reduce Disease Impacts On Sympatric Wild Oysters, Tal Ben-Horin, Colleen Burge, David Bushek, Maya Groner, Dina Proestou, Lauren Huey, Gorka Bidegain, Ryan Carnegie Dec 2018

Intensive Oyster Aquaculture Can Reduce Disease Impacts On Sympatric Wild Oysters, Tal Ben-Horin, Colleen Burge, David Bushek, Maya Groner, Dina Proestou, Lauren Huey, Gorka Bidegain, Ryan Carnegie

VIMS Articles

Risks associated with disease spread from fish and shellfish farming have plagued the growth and public perception of aquaculture worldwide. However, by processing nutrients and organic material from the water column, the culture of many suspension-feeding bivalves has been proposed as a novel solution toward mitigating problems facing coastal water quality, including the removal of disease-causing parasites. Here we developed and simulated an epidemiological model describing sympatric oyster Crassostrea virginica populations in aquaculture and the wild impacted by the protozoan parasite Perkinsus marinus. Our model captured the indirect interaction between wild and cultured populations that occurs through sharing water-borne P. …


Rising Temperatures, Molting Phenology, And Epizootic Shell Disease In The American Lobster, Maya Groner, Jeffrey D. Shields, Df Landers, J Swenarton, Jm Hoenig Nov 2018

Rising Temperatures, Molting Phenology, And Epizootic Shell Disease In The American Lobster, Maya Groner, Jeffrey D. Shields, Df Landers, J Swenarton, Jm Hoenig

VIMS Articles

Phenological mismatchmaladaptive changes in phenology resulting from altered timing of environmental cuesis an increasing concern in many ecological systems, yet its effects on disease are poorly characterized. American lobster (Homarus americanus) is declining at its southern geographic limit. Rising seawater temperatures are associated with seasonal outbreaks of epizootic shell disease (ESD), which peaks in prevalence in the fall. We used a 34-year mark-recapture data set to investigate relationships between temperature, molting phenology, and ESD in Long Island Sound, where temperatures are increasing at 0.4 degrees C per decade. Our analyses support the hypothesis that phenological mismatch is linked to the …


Investigating The Life Cycle Of Haplosporidium Nelsoni (Msx), Se Ford, Na Stokes, Ka Alcox, Bsf Kraus, Rochelle Barber, Ryan Carnegie, Em Burreson Oct 2018

Investigating The Life Cycle Of Haplosporidium Nelsoni (Msx), Se Ford, Na Stokes, Ka Alcox, Bsf Kraus, Rochelle Barber, Ryan Carnegie, Em Burreson

VIMS Articles

Attempts to decipher the life cycle of Haplosporidium nelsoni began almost immediately after it was identified as the pathogen causing MSX disease in eastern oysters, Crassostrea virginica. But transmission experiments failed and the spore stage, characteristic of haplosporidans, was extremely rare. Researchers concluded that another host was involved: an intermediate host in which part of the life cycle was produced, or-if the oyster was an accidental host-an alternate host that produces infective elements. A later finding that spores were found more often in spat (< 1 y old) than in adults revived the idea of direct transmission between oysters. The new findings and the availability of molecular diagnostics led us to revive life cycle investigations. Over several years, oyster spat were examined for spores and searched for H. nelsoni in potential non-oyster hosts using both histological and polymerase chain reaction (PCR) methodologies. …


Dermal Mycobacteriosis And Warming Sea Surface Temperatures Are Associated With Elevated Mortality Of Striped Bass In Chesapeake Bay, Maya L. Groner, John M. Hoenig, Roger Pradel, Remi Choquet, Wolfgang K. Vogelbein, David T. Gauthier, Marjorie A.M. Friedrichs Sep 2018

Dermal Mycobacteriosis And Warming Sea Surface Temperatures Are Associated With Elevated Mortality Of Striped Bass In Chesapeake Bay, Maya L. Groner, John M. Hoenig, Roger Pradel, Remi Choquet, Wolfgang K. Vogelbein, David T. Gauthier, Marjorie A.M. Friedrichs

VIMS Articles

Temperature is hypothesized to alter disease dynamics, particularly when species are living at or near their thermal limits. When disease occurs in marine systems, this can go undetected, particularly if the disease is chronic and progresses slowly. As a result, population-level impacts of diseases can be grossly underestimated. Complex migratory patterns, stochasticity in recruitment, and data and knowledge gaps can hinder collection and analysis of data on marine diseases. New tools enabling quantification of disease impacts in marine environments include coupled biogeochemical hydrodynamic models (to hindcast key environmental data), and multievent, multistate mark-recapture (MMSMR) (to quantify the effects of environmental …


Effects-Based Spatial Assessment Of Contaminated Estuarine Sediments From Bear Creek, Baltimore Harbor, Md, Usa, Se Hartzell, Michael A. Unger, Bl Mcgee, Lt Yonkos Jan 2018

Effects-Based Spatial Assessment Of Contaminated Estuarine Sediments From Bear Creek, Baltimore Harbor, Md, Usa, Se Hartzell, Michael A. Unger, Bl Mcgee, Lt Yonkos

VIMS Articles

The original publication of this paper contains an error. The correct image of figure 5 is shown in this paper.


Impact Of Disease On The Survival Of Three Commercially Fished Species, John M. Hoenig, Maya L. Groner, Matthew W. Smith, Wolfgang K. Vogelbein, David M. Taylor, Donald F. Landers, John T. Swenarton, David T. Gauthier, Philip W. Sadler, Mark A. Matsche, Ashley N. Haines, Hamish J. Small, Roger Pradel, Remi Choquet, Jeffrey D. Shields Oct 2017

Impact Of Disease On The Survival Of Three Commercially Fished Species, John M. Hoenig, Maya L. Groner, Matthew W. Smith, Wolfgang K. Vogelbein, David M. Taylor, Donald F. Landers, John T. Swenarton, David T. Gauthier, Philip W. Sadler, Mark A. Matsche, Ashley N. Haines, Hamish J. Small, Roger Pradel, Remi Choquet, Jeffrey D. Shields

VIMS Articles

Recent increases in emergent infectious diseases have raised concerns about the sustainability of some marine species. The complexity and expense of studying diseases in marine systems often dictate that conservation and management decisions are made without quantitative data on population-level impacts of disease. Mark-recapture is a powerful, underutilized, tool for calculating impacts of disease on population size and structure, even in the absence of etiological information. We applied logistic regression models to mark-recapture data to obtain estimates of disease-associated mortality rates in three commercially important marine species: snow crab (Chionoecetes opilio) in Newfoundland, Canada, that experience sporadic epizootics of bitter …


Vaccine Effects On Heterogeneity In Susceptibility And Implications For Population Health Management, Ke Langwig, Ar Wargo, Dr Jones, Jr Viss, Bj Rutan, Et Al. Jan 2017

Vaccine Effects On Heterogeneity In Susceptibility And Implications For Population Health Management, Ke Langwig, Ar Wargo, Dr Jones, Jr Viss, Bj Rutan, Et Al.

VIMS Articles

Heterogeneity in host susceptibility is a key determinant of infectious disease dynamics but is rarely accounted for in assessment of disease control measures. Understanding how susceptibility is distributed in populations, and how control measures change this distribution, is integral to predicting the course of epidemics with and without interventions. Using multiple experimental and modeling approaches, we show that rainbow trout have relatively homogeneous susceptibility to infection with infectious hematopoietic necrosis virus and that vaccination increases heterogeneity in susceptibility in a nearly all-or-nothing fashion. In a simple transmission model with an R-0 of 2, the highly heterogeneous vaccine protection would cause …


Behavioral Analysis Of Microphallus Turgidus Cercariae In Relation To Microhabitat Of Two Host Grass Shrimp Species (Palaemonetes Spp.), Pa O'Leary, Oj Pung Jan 2017

Behavioral Analysis Of Microphallus Turgidus Cercariae In Relation To Microhabitat Of Two Host Grass Shrimp Species (Palaemonetes Spp.), Pa O'Leary, Oj Pung

VIMS Articles

The behavior of Microphallus turgidus cercariae was examined and compared to microhabitat selection of the second intermediate hosts of the parasite, Palaemonetes spp. grass shrimp. Cercariae were tested for photokinetic and geotactic responses, and a behavioral ethogram was established for cercariae in control and grass shrimp-conditioned brackish water. Photo kinesis trials were performed using a half-covered Petri dish, and geotaxis trials used a graduated cylinder. Both photokinesis and geotaxis trials were performed in lighted and unlighted conditions. In 9 of 10 photokinesis experiments, over half of the cercariae swam horizontally under the covered half of a Petri dish in both …


Replication And Shedding Kinetics Of Infectious Hematopoietic Necrosis Virus In Juvenile Rainbow Trout, Ar Wargo, Rj Scott, B Kerr, G Kurath Jan 2017

Replication And Shedding Kinetics Of Infectious Hematopoietic Necrosis Virus In Juvenile Rainbow Trout, Ar Wargo, Rj Scott, B Kerr, G Kurath

VIMS Articles

Viral replication and shedding are key components of transmission and fitness, the kinetics of which are heavily dependent on virus, host, and environmental factors. To date, no studies have quantified the shedding kinetics of infectious hematopoietic necrosis virus (IHNV) in rainbow trout (Oncorhynchus mykiss), or how they are associated with replication, making it difficult to ascertain the transmission dynamics of this pathogen of high agricultural and conservation importance. Here, the replication and shedding kinetics of two M genogroup IHNV genotypes were examined in their naturally co-evolved rainbow trout host. Within host virus replication began rapidly, approaching maximum values by day …


Impact Of Environment And Ontogeny On Relative Fecundity And Egg Quality Of Female Oysters (Crassostrea Virginica) From Four Sites In Northern Chesapeake Bay, Hl Glandon, Ak Michaelis, Et Al, Kimberly S. Reece, Et Al Dec 2016

Impact Of Environment And Ontogeny On Relative Fecundity And Egg Quality Of Female Oysters (Crassostrea Virginica) From Four Sites In Northern Chesapeake Bay, Hl Glandon, Ak Michaelis, Et Al, Kimberly S. Reece, Et Al

VIMS Articles

Resource allocation to reproduction is a primary physiological concern for individuals, and can vary with age, environment, or a combination of both factors. In this study we quantified the impact of environment and individual age on the reproductive output of female oysters Crassostrea virginica. We determined the relative fecundity, egg total lipid content, and overall and omega- 3/omega-6 fatty acid signatures (FAS) of eggs spawned by female oysters over a 2-year period (n = 32 and n = 64). Variation was quantified spatially and ontogenetically by sampling young and old oyster populations from two rivers in Chesapeake Bay, totaling four …


Effects Of Embryonic Exposure To Salinity Stress Or Hypoxia On Post-Metamorphic Growth And Survival Of The Polychaete Capitella Teleta, Ja Pechenik, Or Chaparro, A Pilnick, M Karp, M Acquafredda, R Burns Jan 2016

Effects Of Embryonic Exposure To Salinity Stress Or Hypoxia On Post-Metamorphic Growth And Survival Of The Polychaete Capitella Teleta, Ja Pechenik, Or Chaparro, A Pilnick, M Karp, M Acquafredda, R Burns

VIMS Articles

Although a good number of studies have investigated the impact of larval experience on aspects of post-metamorphic performance, only a few have considered the potential impact of stresses experienced by brooded embryos. In this study we separately investigated the impact of salinity stress (as low as 10) and hypoxia (1 ml O2 1 sub-1) experienced by brooded embryos of the deposit-feeding polychaete Capitella teleta on hatching success, metamorphosis, post-metamorphic survival, and post-metamorphic growth. Salinity reduction from 30 to 10 or 15 reduced relative hatching success, presumably by reducing embryonic survival, but generally had no negative latent effects on juvenile survival …


Managing Aquatic Parasites For Reduced Drug Resistance: Lessons From The Land, Gf Mcewan, Ml Groner, Dl Burnett, Md Fast, Cw Revie Jan 2016

Managing Aquatic Parasites For Reduced Drug Resistance: Lessons From The Land, Gf Mcewan, Ml Groner, Dl Burnett, Md Fast, Cw Revie

VIMS Articles

Atlantic salmon farming is one of the largest aquaculture industries in the world. A major problem in salmon farms is the sea louse ectoparasite Lepeophtheirus salmonis, which can cause stress, secondary infection and sometimes mortality in the salmon host. Sea lice have substantial impacts on farm economics and potentially nearby wild salmonid populations. The most common method of controlling sea louse infestations is application of chemicals. However, most farming regions worldwide have observed resistance to the small set of treatment chemicals that are available. Despite this, there has been little investigation of treatment strategies for managing resistance in aquaculture. In …


First Report Of Perkinsus Honshuensis In The Variegated Carpet Shell Clam Ruditapes Variegatus In Korea, Hs Kang, Hs Yang, Kimberly S. Reece, Hk Hong, Ki Park, Ks Choi Jan 2016

First Report Of Perkinsus Honshuensis In The Variegated Carpet Shell Clam Ruditapes Variegatus In Korea, Hs Kang, Hs Yang, Kimberly S. Reece, Hk Hong, Ki Park, Ks Choi

VIMS Articles

The recent discovery of Perkinsus honshuensis, a new Perkinsus species infecting Manila clams Ruditapes philippinarum (Sowerby, 1852), in Japan, suggested that, based on proximity, P. honshuensis could also be in Korean waters, where to date, P. olseni was believed to be the only Perkinsus species present. Perkinsus sp. infections consistently occurred among Ruditapes variegatus clams on a pebble beach on Jeju Island, off the south coast of Korea. The typical 'signet ring' morphology of the parasite was observed in the connective tissue of the digestive gland, and infection intensity was comparatively low (3.3 x 10(3) +/- 1.2 x 10(4) to …