Brook trout Salvelimts fontinalis were treated with single 60-min static baths of 250 mg formalin/L. 3 r # NaCL and 15 mg Chloramine-T/L to evaluate the efficacy of these compounds against external infections of Aeromonas salmonicida. Prevalence of A. salmonicida was significantly lower in brook trout treated with Chloramine-T than among those treated with formalin or salt. Further laboratory tests substantiated the therapeutic value of a single treatment of Chloramine-"I' (15 mg/L) against A. salmonicida. In two experiments, viable counts of A. salmonicida in mucus did not vary among replicate groups of treated brook trout, but the counts for treated fish were significantly (P < 0.05) lower than those for untreated controls. In vitro tube dilution assays indicated that mean minimum inhibitory concentrations of Chloramine-T for 10 isolates of A. salmonicida were 9.0 mg/L for I h and 2.25 mg/L for 24 h. In field trials at the White River National Fish Hatchery (Bethel, Vermont), the pathogen was detected principally as an external infection of juvenile Atlantic salmon Salmo salar maintained in two culture ponds. In one pond, the bacterium accounted for 100% of the total distribution of microflora isolated from mucus. Seven days after treatment with Chloramine-T. A. salmonicida accounted for 11% of the total bacterial counts identified from these fish. In the second pond. A. salmonicida composed 3% of the counts of bacteria isolated from the mucus of fish before treatment but was not isolated after treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.