AIM To develop a method for conducting pulsed-field gel electrophoresis (PFGE) on Flavobacterium columnare, to use PFGE to characterize F. columnare channel catfish isolates, and to determine whether variation in pathogenic potential exists in F. columnare isolates from channel catfish. METHODS AND RESULTS On the basis of PFGE-derived profiles, similarity dendrograms constructed for more than...

The pathogenicity of a Streptococcus ictaluri isolate in channel catfish Ictalurus punctatus at the fry (0.5 g), fingerling (15 g), and juvenile (55 g) stages was determined by experimental bath immersion and injection experiments. Channel catfish were exposed in 1-L immersion baths containing 10(8), 10(9), 10(10), 10(11) or 10(12) colony-forming units (cfu) of S. ictaluri. Fish were also injec...

To identify differentially expressed genes from channel catfish macrophages, a cDNA library from LPS-stimulated catfish macrophages was screened by subtractive hybridization. This screening yielded a 552-bp cDNA coding for catfish thioredoxin (CF-TRX). The deduced amino acid sequence revealed that CF-TRX contains 107 amino acids and is 59% homologous to human adult T cell leukemia-derived facto...

The present experiments were designed to determine the efficacy of metomidate hydrochloride as an alternative anesthetic with potential cortisol blocking properties for channel catfish Ictalurus punctatus. Channel catfish (75 g) were exposed to concentrations of metomidate ranging from 0.5 to 16 ppm for a period of 60 min. At 16-ppm metomidate, mortality occurred in 65% of the catfish. No morta...

Ferritins are the major iron storage protein in the cytoplasm of cells, responsible for regulating levels of intracellular iron. Ferritin genes are widely distributed in both prokaryotes and eukaryotes. In mammals, ferritin molecules are composed of heavy- (H) and light- (L) chain subunits; amphibian genomes contain three ferritin-type genes (H; middle, M; and L subunits); and teleost genomes t...

A 15-wk study was conducted to evaluate the effect of supplemental menhaden fish oil levels and feeding duration on growth performance and tissue proximate and fatty acid (FA) compositions of juvenile channel catfish, Ictalurus punctatus. Dietary fish oil levels had no effect on final weight gain, feed efficiency, and survival of channel catfish. Tissue lipid contents were directly correlated t...

The purpose of this study is to describe the histological and histochemical features of digestive tract intwo aquarium fishes with different types of feeding habits which are omnivorous (Walking catfish) andcarnivorous (piranha), respectively. Five adult Walking catfish (L: 26.4 ± 3.4 cm, W: 265 ± 55 g) and fiveadult piranha (L: 23.6 ± 4.5 cm, W: 247 ± 50 g) were used for this study. The fishes...