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Full-Text Articles in Life Sciences
Perkinsus Marinus Susceptibility And Defense-Related Activities In Eastern Oysters Crassostrea Virginica: Temperature Effects, Fu-Lin E. Chu, Jerome F. La Peyre
Perkinsus Marinus Susceptibility And Defense-Related Activities In Eastern Oysters Crassostrea Virginica: Temperature Effects, Fu-Lin E. Chu, Jerome F. La Peyre
VIMS Articles
he relationship of potential defense-related cellular and humoral activities and the sus- ceptibility of eastern oysters Crassostrea virginica to the parasite Perkinsus marinus were examined at 10, 15, 20 and 25 "C. Oysters were acclimated at experimental temperatures for 20 d and then chal- lenged with R marinus. Total hemocyte counts (TC) and percentage of granulocytes (PG) 20 d after temperature acclimation were higher in oysters at high than at low acclimation temperature. Higher protein (P) and lysozyme (L) concentrations were found in oysters at 10 and 15 "C. No significant differ- ences in hemagglutination (H) titers due to temperature …
Development Of Disease Caused By The Parasite, Perkinsus-Marinus And Defense-Related Hemolymph Factors In 3 Populations Of Oysters From The Chesapeake Bay, Usa, Fu-Lin C. Chu, J.F. La Peyre
Development Of Disease Caused By The Parasite, Perkinsus-Marinus And Defense-Related Hemolymph Factors In 3 Populations Of Oysters From The Chesapeake Bay, Usa, Fu-Lin C. Chu, J.F. La Peyre
VIMS Articles
The development of infection caused by the protozoan parasite, Perkinsus marinus (Dermo) and some specific potential defense-related cellular and humoral components in oysters collected from three geographic areas, Deepwater Shoal of James River (DW), Wachapreague (WP), and Mobjack Bay (MJ) were examined over time. Oysters were maintained in estuarine water (salinity = 20 ppt) or in water at a salinity similar to the ambient salinity of the collection sites. Oysters were sampled at the initiation of the experiment (day 0), day 35, and day 100 to determine defense-related parameters and disease prevalence and intensity. All populations experienced a significant increase …
Spatial And Temporal Bacterioplankton Dynamics During Destratification Of The James River Estuary, Virginia, Usa, Et Koepfler, Hi Kator, Rl Wetzel, Lw Haas
Spatial And Temporal Bacterioplankton Dynamics During Destratification Of The James River Estuary, Virginia, Usa, Et Koepfler, Hi Kator, Rl Wetzel, Lw Haas
VIMS Articles
Bacterioplankton abundance and production were examined over the course of a destratification event in the lower James River, Virginia, USA, Goals of the study were to determine if destratification would influence temporal patterns of bacterioplankton parameters and relationships between bacterioplankton and other biological and abiological parameters. Mean bacterial abundance grouped over stations did not change over the course of the study, and were characterized by much smaller coefficients of variation than all other planktonic constituents. However, bacterial production measured by H-3-thymidine (H-3-Tdr) incorporation decreased significantly from a stratified (324 mu g Cl-1 d(-1)) to a destratified (187 mu g Cl-1 …
Effect Of Salinity On Infection Progression And Pathogenicity Of Perkinsus-Marinus In The Eastern Oyster, Crassostrea-Virginica (Gmelin), Lisa M. Ragone, Eugene M. Burreson
Effect Of Salinity On Infection Progression And Pathogenicity Of Perkinsus-Marinus In The Eastern Oyster, Crassostrea-Virginica (Gmelin), Lisa M. Ragone, Eugene M. Burreson
VIMS Articles
The effect of salinity on Perkinsus marinus, a protozoan pathogen of the eastern oyster, Crassostrea virginica (Gmelin 1791) was investigated. Oysters parasitized by P. marinus were exposed in the laboratory to 6, 9, 12, and 20 ppt at a temperature ranging from 20-25-degrees-C, for an eight week period. Infection prevalence and intensity were assessed in samples (n = 25) from each treatment following 2, 4, 6, and 8 weeks of exposure and oyster mortality was determined daily. The pathogen persisted, at high prevalences, throughout the course of the experiment at all treatment salinities; however, P. marinus infection development was retarded …
Effects Of 2 Bloom-Forming Dinoflagellates, Prorocentrum-Minimum And Gyrodinium-Uncatenum, On The Growth And Survival Of The Eastern Oyster, Crassostrea-Virginica (Gmelin 1791), Mark Luckenbach, Kg Sellner, Se Shumway, K Greene
Effects Of 2 Bloom-Forming Dinoflagellates, Prorocentrum-Minimum And Gyrodinium-Uncatenum, On The Growth And Survival Of The Eastern Oyster, Crassostrea-Virginica (Gmelin 1791), Mark Luckenbach, Kg Sellner, Se Shumway, K Greene
VIMS Articles
Laboratory experiments were conducted to investigate the effects of the dinoflagellates Prorocentrum minimum and Gyrodinium uncatenum on the growth and survival of juvenile eastern oysters, Crassostrea virginica. In separate experiments lasting 30 d and 18 d for P. minimum and G. uncatenum, respectively, the dinoflagellates were offered to the oysters in both unialgal and mixed diets (with the diatom Thalassiosira weisflogii). Eight diets were used in each experiment: (i) the dinoflagellate at bloom density, (ii) the dinoflagellate at 33% bloom density, (iii) the dinoflagellate at 5% bloom density, (iv-vi) the diatom at the above densities, (vii) 50% dinoflagellate bloom density …