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Full-Text Articles in Life Sciences
Isolation And Characterization Of Serine Protease Gene(S) From Perkinsus Marinus, Gd Brown, Kimberly S. Reece
Isolation And Characterization Of Serine Protease Gene(S) From Perkinsus Marinus, Gd Brown, Kimberly S. Reece
VIMS Articles
This study reports the first serine protease gene(s) isolated from Perkinsus marinus. Using universal primers, a 518 bp subtilisin-like serine protease gene fragment was amplified from P, marinus genomic DNA and used as a probe to screen a lambda-phage P. marinus genomic library; 2 different gamma-phage clones hybridized to the digoxigenin(DIG)-labeled subtilisin-like gene fragment. Following subcloning and sequencing of the larger DNA fragment, a 1254 bp open reading frame was identified and later confirmed, by 5' and 3' random amplification of cDNA ends (RACE) and northern blot analysis, to contain the entire coding-region sequence. Sequence analysis of the 3' RACE …
Systematic Evaluation Of Factors Controlling Perkinsus Marinus Transmission Dynamics In Lower Chesapeake Bay, Lm Ragone Calvo, Cf Dungan, Bs Roberson, Em Burreson
Systematic Evaluation Of Factors Controlling Perkinsus Marinus Transmission Dynamics In Lower Chesapeake Bay, Lm Ragone Calvo, Cf Dungan, Bs Roberson, Em Burreson
VIMS Articles
The transmission of Perkinsus marinus in eastern oysters Crassostrea virginica in relation to water temperature, host oyster mortality, and water-column abundance of anti-P. marinus antibody-labeled cells was systematically examined for 20 mo at a site in the lower York River, Virginia, USA. Uninfected sentinel oysters were naturally exposed to the parasite at 2 wk intervals throughout the course of the study to determine the periodicity and rates of parasite transmission. The timing and magnitude of disease-associated oyster mortalities in a local P. marinus-infected oyster population were estimated by monitoring a captive subset of the local oyster population. Flow cytometric immunodetection …
Detection Of The Oyster Parasite Bonamia Ostreae By Fluorescent In Situ Hybridization, Ryan Carnegie, Bj Barber, Dl Distel
Detection Of The Oyster Parasite Bonamia Ostreae By Fluorescent In Situ Hybridization, Ryan Carnegie, Bj Barber, Dl Distel
VIMS Articles
Bonamia ostreae is an economically significant protistan parasite of the flat oyster Ostrea edulis in Europe and North America. Management of this parasite depends partly upon its reliable identification in wild and aquacultured oyster populations, but B. ostreae is small and difficult to detect by traditional microscopic methods. We designed a fluorescent in situ hybridization (FISH) assay to sensitively detect B. ostreae in standard histopathological sections of B. ostreae-infected oysters using fluorescently labeled DNA oligonucleotide probes. Hybridization using a cocktail of 3 presumptively B. ostreae-specific, fluorescein iso(thio)cyanate (FITC)-labeled oligonucleotides produced an unambiguous staining pattern of small green rings inside infected …
Molecular Detection Of The Oyster Parasite Mikrocytos Mackini, And A Preliminary Phylogenetic Analysis, Ryan Carnegie, Gr Meyer, Et Al
Molecular Detection Of The Oyster Parasite Mikrocytos Mackini, And A Preliminary Phylogenetic Analysis, Ryan Carnegie, Gr Meyer, Et Al
VIMS Articles
The protistan parasite Mikrocytos mackini, the causative agent of Denman Island disease in the oyster Crassostrea gigas in British Columbia, Canada, is of wide concern because it can infect other oyster species and because its life cycle, mode of transmission, and origins are unknown. PCR and fluorescent in situ hybridization (FISH) assays were developed for M mackini, the PCR assay was validated against standard histopathological diagnosis, and a preliminary phylogenetic analysis of the M mackini small-subunit ribosomal RNA gene (SSU rDNA) was undertaken. A PCR designed specifically not to amplify host DNA generated a 544 bp SSU rDNA fragment from …
Mikrocytos Roughleyi Taxonomic Affiliation Leads To The Genus Bonamia (Haplosporidia), N Cochennec-Laureau, Kimberly S. Reece, Fcj Berthe, Pm Hine
Mikrocytos Roughleyi Taxonomic Affiliation Leads To The Genus Bonamia (Haplosporidia), N Cochennec-Laureau, Kimberly S. Reece, Fcj Berthe, Pm Hine
VIMS Articles
Microcell-type parasites of oysters are associated with a complex of diseases in different oyster species around the world. The etiological agents are protists of very small size that are very difficult to characterize taxonomically. Associated lesions may vary according to the host species, and their occurrence may be related to variations in tissue structure. Lesion morphology cannot be used to distinguish the different agents involved. Ultrastructural observations on Mikrocytos roughleyi revealed similarities with Bonamia spp., particularly in regard to the presence of electron-dense haplosporosomes and mitochondria, whose absence from M mackini also indicate that M roughleyi and M mackini are …
Research Priorities For Diseases Of The Blue Crab Callinectes Sapidus, Jeffrey D. Shields
Research Priorities For Diseases Of The Blue Crab Callinectes Sapidus, Jeffrey D. Shields
VIMS Articles
The diseases of blue crabs have received relatively little attention compared to those of the American oyster, Crassostrea virginica, or the penaeid shrimps, Penaeus spp. This is primarily due to differences in resource management (fishery vs. aquaculture), and the magnitude of financial losses suffered by the industries from protozoal diseases in oysters and viral diseases in shrimp, respectively. Nonetheless, several agents including Vibrio spp., Hematodinium perezi, Paramoeba perniciosa, Ameson michaelis and Loxothylacus texanus are highly pathogenic in blue crabs, and have the capacity to severely damage certain segments of the crab population. This paper is meant to highlight priorities for …
Aspects Of The Pathophysiology Of Blue Crabs, Callinectes Sapidus, Infected With The Parasitic Dinoflagellate Hematodinium Perezi, Jeffrey D. Shields, C Scanlon, A Volety
Aspects Of The Pathophysiology Of Blue Crabs, Callinectes Sapidus, Infected With The Parasitic Dinoflagellate Hematodinium Perezi, Jeffrey D. Shields, C Scanlon, A Volety
VIMS Articles
Blue crabs, Callinectes sapidus, infected with Hematodinium perezi frequently show signs of weakness and lethargy and die when stressed by handling or capture. Radical changes to the hemolymph of heavily infected crabs are obvious by reduced clotting ability, discoloration. and a 50% to 70% decline in total hemocyte density. Few other signs of infection are associated with infections and the resulting mortalities of blue crabs. To assay physiological changes in infected crabs, we measured serum proteins, hemocyanin, serum acid phosphatase, various hemolymph enzymes, hernagglutination activity, and tissue glycogen levels in relation to intensity of infection with H. perezi. Serum proteins …
Experimental Mycobacteriosis In Striped Bass Morone Saxatilis, Dt Gauthier, Mw Rhodes, Wolfgang K. Vogelbein, H Kator, Ca Ottinger
Experimental Mycobacteriosis In Striped Bass Morone Saxatilis, Dt Gauthier, Mw Rhodes, Wolfgang K. Vogelbein, H Kator, Ca Ottinger
VIMS Articles
Striped bass Morone saxatilis were infected intraperitoneally with approximately 10(5) Mycobacterium marinum, M. shottsii sp. nov., or M. gordonae. Infected fish were maintained in a flow-through freshwater system at 18 to 21degreesC, and were examined histologically and bacteriologically at 2, 4, 6, 8, 17, 26, 36 and 45 wk post-infection (p.i.). M. marinum caused acute peritonitis, followed by extensive granuloma development in the mesenteries, spleen and anterior kidney. Granulomas in these tissues underwent a temporal progression of distinct morphological stages, culminating in well-circumscribed lesions surrounded by normal or healing tissue. Mycobacteria were cultured in high numbers from splenic tissue at …
Infectivity And Pathogenicity Of The Oomycete Aphanomyces Invadans In Atlantic Menhaden Brevoortia Tyrannus, Y Kiryu, Jeffrey D. Shields, Wolfgang K. Vogelbein, H Kator, Vs Blazer
Infectivity And Pathogenicity Of The Oomycete Aphanomyces Invadans In Atlantic Menhaden Brevoortia Tyrannus, Y Kiryu, Jeffrey D. Shields, Wolfgang K. Vogelbein, H Kator, Vs Blazer
VIMS Articles
Atlantic menhaden Brevoortia tyrannus develop characteristic skin ulcers in response to infection by the oomycete Aphanomyces invadans. To investigate pathogenicity, we conducted a dose response study. Juvenile menhaden were inoculated subcutaneously with 0, 1, 5, 10, 100, and 500 secondary zoospores per fish and monitored for 37 d post-injection (p.i.). Survival rates declined with increasing zoospore dose, with significantly different survivorship curves for the different doses. Moribund and dead fish exhibited characteristic ulcerous lesions at the injection site starting at 13 d p.i. None of the sham-injected control fish (0 zoospore treatment) died. The LD50 (lethal dose killing 50% of …
Mycobacterium Shottsii Sp Nov., A Slowly Growing Species Isolated From Chesapeake Bay Striped Bass (Morone Saxatilis), Mw Rhodes, H Kator, S Kotob, P Van Berkum, I Kaattari, Wolfgang K. Vogelbein, Et Al
Mycobacterium Shottsii Sp Nov., A Slowly Growing Species Isolated From Chesapeake Bay Striped Bass (Morone Saxatilis), Mw Rhodes, H Kator, S Kotob, P Van Berkum, I Kaattari, Wolfgang K. Vogelbein, Et Al
VIMS Articles
Slowly growing, non-pigmented mycobacteria were isolated from striped bass (Morone saxatilis) during an epizootic of mycobacteriosis in the Chesapeake Bay. Growth characteristics, acid-fastness and results of 16S rRNA gene sequencing were consistent with those of the genus Mycobacterium. A unique profile of biochemical reactions was observed among the 21 isolates. A single cluster of eight peaks identified by analysis of mycolic acids (HPLC) resembled those of reference patterns but differed in peak elution times from profiles of reference species of the Mycobacterium tuberculosis complex. One isolate (M175(T)) was placed within the slowly growing mycobacteria by analysis of aligned 16S rRNA …
Molecular Analysis Of A Haplosporidian Parasite From Cultured New Zealand Abalone Haliotis Iris, Kimberly S. Reece, Na Stokes
Molecular Analysis Of A Haplosporidian Parasite From Cultured New Zealand Abalone Haliotis Iris, Kimberly S. Reece, Na Stokes
VIMS Articles
In the Austral summer and autumn of 2000 and 2001, mortalities of black-footed abalone Haliotis iris (Martyn, 1784) occurred in a commercial facility in New Zealand. Histological analyses suggested that infection by a haplosporidian parasite was responsible. To confirm identification as a haplosporidian and to help determine if this parasite represented a new, undescribed species, DNA was extracted from infected host tissues scored as positive for infection by histological examination. Small-subunit rRNA (SSU rRNA) gene sequences from both the host abalone and a parasitic organism were amplified by PCR and characterized. Although the sequence for this parasite was novel, not …
Monitoring The Prevalence Of The Parasitic Dinoflagellate Hematodinium Sp In Snow Crabs Chionoecetes Opilio From Conception Bay, Newfoundland, Gp Pestal, Dm Taylor, Jm Hoenig, Jeffrey D. Shields, R Pickavance
Monitoring The Prevalence Of The Parasitic Dinoflagellate Hematodinium Sp In Snow Crabs Chionoecetes Opilio From Conception Bay, Newfoundland, Gp Pestal, Dm Taylor, Jm Hoenig, Jeffrey D. Shields, R Pickavance
VIMS Articles
Bitter crab disease (BCD) of snow crabs Chionoecetes opilio is caused by a parasitic dinoflagellate, Hematodinium sp. In Newfoundland's commercial fishery, infected snow crabs are identified using visual, macroscopic signs of disease for separation prior to processing. We estimated the sensitivity and specificity of gross, macroscopic diagnosis of Hematodinium sp. by comparing these results with microscopic examination of prepared hemolymph smears. The sensitivity of a diagnostic test is the probability that the test will yield a positive result given that the animal has the disease. The specificity is the probability of a negative result given the animal is not diseased. …
Perkinsus Sp Infection Risk For Manila Clams, Venerupis Philippinarum (A. Adams And Reeve, 1850) On The Pacific Coast Of North And Central America, Ra Elston, Cf Dungan, Tr Meyers, Kimberly S. Reece
Perkinsus Sp Infection Risk For Manila Clams, Venerupis Philippinarum (A. Adams And Reeve, 1850) On The Pacific Coast Of North And Central America, Ra Elston, Cf Dungan, Tr Meyers, Kimberly S. Reece
VIMS Articles
Manila clams (Venerupis philippinarum, A. Adams and Reeve 1850) are an important aquaculture species on the west coast of North America and are also cultured in Europe, Asia, and other locations. Clams cultured on the west coast of North America are free of Perkinsus sp. infections, while clams from certain Asian and European sources are infected. Infection in Korean Manila clams is reportedly associated with high morbidity and mortality. We evaluated the health status of readily accessible Manila clam juveniles from Korea that were proposed for importation into Mexican waters where they would increase in size, and then be shipped …