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J.J.A. McLaughlin

Publications and source records attributed to J.J.A. McLaughlin.

2 recordsLinked to original sources

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

Effects of five metals on susceptibility of striped bass to Flexibacter columnaris

Exposure of young striped bass Morone saxatilis (weight, 8.5–34 g) to a mixture of arsenic, cadmium, copper, lead, and selenium at 4 and 10 times the average environmental concentrations of 1–3 μg/L protected the fish from experimental infection with Flexibacter columnaris, the causal organism of columnaris disease. In four trials, all striped bass died within 7 d after a 2‐min exposure to 5 × 10 6 F. columnaris cells in untreated water. In contrast, no fish died after a single dayˈs exposure to the metal mixture followed by infection with F. columnaris and a second exposure to the metals for seven more days. When striped bass were exposed 5 d to individual metals, copper protected against infection and cadmium offered marginal protection but was slightly toxic after 2 d exposure. Arsenic increased susceptibility to infection, and lead and selenium were without an apparent effect.

Transactions of the American Fisheries Society