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C. E. Starliper

Publications and source records attributed to C. E. Starliper.

35 records · Page 2Linked to original sources
USGS1996

Genetic diversity of North American isolates of Renibacteriumsalmoninarum

Genetic diversity of Renibacterium salmoninarum was evaluated by multilocus enzyme electrophoresis (MEE). Whole cell lysates were prepared for 40 isolates representing 5 groups based on host and geographic area. Each lysate was assessed for activity of 44 enzymes with a pH 6.5 amine-citrate and a pH 8.0 buffer. Genetic variation was scored at 26 loci. Two zones of activity (presumptive loci) were scored each for esterase (EC 3.1.1.1) and glycyl-leucine peptidase (EC 3.4.11.x). There were no monomorphic loci and there was an average of 2.65 electromorphs per locus. There were 21 electrophoretic types. Mean genetic diversity ( H T ) was 0.161 and the percentage of this explained by diversity between groups was G st = 8.1%; thus 91.9% of the genetic diversity was due to heterogeneity between individual isolates. The 2 groups with the highest genetic diversity were from chinook Oncorhynchus tshawytscha and coho O . kisutch salmon, both from the Manistee Weir, Michigan, USA; i.e. 0.270 and 0.298, respectively. The highest genetic diversity for a locus ( h T ) was 0.587 for EST-1. At this locus, diversity between groups explained a higher percentage of the total diversity ( G st = 36.5%). Other loci with relatively high genetic diversity were succinate dehydrogenase (0.385; EC 1.3.99.1), cytochrome c oxidase (0.273; EC 1.9.3.1) and aconitase (0.311; EC 4.2.1.3). The results of this study indicate relatively low genetic diversity of R . salmoninarum .

Diseases of Aquatic Organisms↗
USGS1993

Plasmid-mediated romet resistance of Edwardsiella ictaluri

Romet®, a potentiated sulfa drug composed of five parts sulfadimethoxine and one part ormetoprim, is used to treat channel catfish Ictalurus punctatus infected with Edwardsiella ictaluri , the causal agent of enteric septicemia of catfish (ESC). Recently, several Romet-resistant isolates of E. ictaluri were isolated from channel catfish that had died from ESC in Virginia and Mississippi. This antimicrobial resistance was determined to be plasmid-encoded, as shown by agarose gel electrophoresis of plasmid DNA, and by the fact that the plasmid and associated antimicrobial resistance could be transferred to a recipient by single-step conjugation. Size of the R plasmid was approximately 55 kilobase pairs. Plasmids also conferred resistance to tetracycline, oxytetracycline, streptomycin, trimethoprim, and SXT (another potentiated sulfonamide, composed of trimethoprim and sulfamethoxazole). Each Romet-resistant E. ictaluri isolate was mated with a plasmid recipient, the Romet-sensitive Escherichia coli isolate 1932. Transconjugates were selected by plating on Mueller-Hinton agar that contained antimicrobials, and the mean transfer frequency was 1.483 × 10 −3 transconjugates per donor cell in the mating mixture. Each E. coli transconjugate was then mated with 20 Romet-sensitive isolates of E. ictaluri to assess the propensity of these E. ictaluri isolates to accept the R plasmid. The average transfer frequency when E. ictaluri isolates of channel catfish origin (N = 14) were used as recipients was 1.197 × 10 −2 transconjugates per donor cell in the mating mixture; mean transfer frequency when E. ictaluri isolates not originating from channel catfish were used was 1.019 × 10 -3 transconjugates per donor cell, which was significantly less (P = 0.0002).

Journal of Aquatic Animal Health↗
USGS1985

Comparative sensitivities of diagnostic procedures used to detect bacterial kidney disease in salmonid fishes

Kidney and spleen homogenates from each of 60 coho salmon ( Oncorhynchus kisutch ) and steelhead trout ( Salmo gairdneri ) were examined for detection of Renibacterium salmoninarum . The proportions of positives differed widely with the detection procedures used: in coho salmon, 5% were positive by the Gram-stain procedure, 10% by the direct fluorescent antibody test, 48% by bacteriological isolation, 65% by staphylococcal coagglutination, and 73% by counterimmunoelectrophoresis; in steelhead trout, 3% were positive by Gram-stain, 8.3% by fluorescent antibody, 17% by bacteriological isolation, and 67% by counterimmunoelectrophoresis. Renibacterium salmoninarum was not detected in either coho salmon or steelhead trout by immunodiffusion analysis.

Journal of Wildlife Diseases↗
USGS1985

Detection of Vibrio anguillarum antigen by the dot blot assay

The dot blot assay, modified and adapted for detection of antigens from Vibrio anguillarum in fish tissues, was specific for V. anguillarum and did not react with antigens of V. ordalii , Pseudomonas sp., or Yersinia ruckeri . The blot assay enabled detection of as little as 2.3 ng of a mixture of protein antigens obtained from cell-free extracts of V. anguillarum ; it was about 100 times more sensitive than either the indirect fluorescent antibody technique or bacterial isolation for detecting V. anguillarum in fish tissues.

Journal of Wildlife Diseases↗
USGS1982

Immersion and injection vaccination of salmonids against furunculosis with an avirulent strain of Aeromonas salmonicida

Replicate groups of brook trout (Salvelinus fontinalis) immunized by intraperitoneal injection of graded dilutions of an avirulent strain of Aeromonas salmonicida were protected from a virulent challenge. Mean mortality after challenge was 88% in control trout, 66% in trout immunized with 3 × 10 6 or 3 × 10 5 cells, and 39% in trout immunized with 3 × 10 4 to 3 × 10¹ cells. In brook trout challenged after immersion for 60 s in a culture containing 2.3 × 10 9 avirulent cells of A. salmonicida per milliliter, mortality was 44%, compared with 94% in controls. In Atlantic salmon (Salmo salar), similarly vaccinated by immersion, mortality was 12.5% after challenge compared with 87.5% in controls. In additional studies, mean mortality of Atlantic salmon vaccinated by immersion was 14%, whereas that of control salmon was 92%.

Progressive Fish-Culturist↗