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S. W. Pyle

Publications and source records attributed to S. W. Pyle.

9 recordsLinked to original sources
USGS1990

Serological investigation of the fish pathogen Edwardsiella ictaluri, cause of enteric septicemia of catfish

The serological relationships among 32 isolates of Edwardsiella ictaluri obtained from fish were studied. The strains were extremely homogeneous in protein and lipopolysaccharide preparations as observed by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis. Only minor variations were observed in the structural O-side chain subunits in three isolates; however, such variation did not preclude antigenic recognition by two E. ictaluri antisera in either microagglutination or Western blot immunoassays. The antigenic homogeneity of E. ictaluri was further demonstrated by microagglutination assays with both formalin-killed and heat inactivated cellular antigens. The minimal degree of antigenic variability observed suggested that most isolates of E. ictaluri compose a single antigenic serotype.

Journal of Wildlife Diseases↗
USGS1986

An epizootic in chinook salmon (Oncorhynchus tshawytscha) caused by a sorbitol-positive serovar 2 strain of Yersinia ruckeri

Enteric redmouth disease is described in chinook salmon ( Oncorhynchus tshawytscha ) at a state hatchery in Sand Ridge, Illinois. Biochemical, isoenzyme, and serological data indicated that the epizootic was caused by a sorbitol-fermenting Serovar 2 strain of Yersinia ruckeri . In laboratory experiments the isolate was pathogenic for both brook trout ( Salvelinus fontinalis ) and Atlantic salmon ( Salmo salar ).

Journal of Wildlife Diseases↗
USGS1985

Rapid serological analysis of bacterial lipopolysaccharides by electrotransfer to nitrocellulose

Techniques are described for the rapid screening of proteinase K-treated bacterial lysates by electroblot and immunoenzymatic detection to assess O-specificity of antigens and antisera. Conditions are outlined which permit the use of a single polyacrylamide gel for both electrotransfer to nitrocellulose and silver staining. Immunodetection of transferred LPS bands was equally sensitive to silver stain when whole cell or O-specific antisera were used. The techniques were utilized to identify at least 4 O-serotypes among sorbitol fermenting isolates of the fish pathogen, Yersinia ruckeri . Observed variations in the electrophoretic mobilities of lipopolysaccharides from 17 field isolates of Y. ruckeri were used to accurately predict the O-serotype.

Journal of Immunological Methods↗
USGS1985

Immune response of channel catfish, Ictalurus punctatus Rafinesque, to bacterial and protozoan antigens administered by three routes

Experiments were conducted to measure the agglutinating antibody response of channel catfish to a particulate and a soluble antigen administered simultaneously by one of three routes. Specific antibody production in response to administration of particulate brucella tube-test antigen via intramuscular injection, oral drench, and topical application peaked at 3 weeks in channel catfish held under identical conditions at 21°C. The humoral antibody response was greater in fish injected with antigen than in the orally or topically exposed channel catfish. Specific antibody was also produced by the same channel catfish in response to the administration of a soluble ciliary preparation derived from Tetrahymena pyriformis Lwoff. Intramuscular injection of Tetrahymena antigen was the only route that produced detectable levels of circulating antibody as measured by direct agglutination of live T. pyriformis cells. The response to the soluble antigen also peaked at 3 weeks. Neither antigen elicited detectable agglutinins in cutaneous mucus, regardless of the vaccination method used.

Aquaculture↗
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↗
USGS1984

Multilocus electrophoretic assessment of the genetic structure and diversity of Yersinia ruckeri

Multilocus isoenzyme electrophoresis was used to screen 47 field isolates of Yersinia ruckeri for electrophoretic variation at 15 enzyme loci. Only four electrophoretic types were observed, thus indicating that the genetic structure of Y. ruckeri is clonal. Forty-two isolates were of one electrophoretic type, a reflection of the low amount of genetic diversity extant in this species. Although sorbitol fermentation has been considered to be indicative of a second biotype, no significant gene frequency differences were found between the group of 20 isolates that readily used sorbitol as the sole carbon source and the group of 27 that did not.

Applied and Environmental Microbiology↗