Abstract
The present authors have been studing on vibriosis (Vibrio anguillarum infection) in ayu (Plecoglossus altivelis) from the viewpoint of control.
Prior to the main experiment, several experimental challenge methods were examined in oredr to establish a reproducible artificial challenge system of vibriosis.
This paper deals with the validity of the artificial challenge system by intramuscular inoculation and a practical application of this system to testing the efficacy of oral-administered drugs for ayu.
The results are summarized as follows.
1) The minimal lethal dose of a strain of Vibrio anguillarum used in this study proved to be 8.75 cells or 1×10 mg-8 in wet weight per 100 g of body weight of ayu.
2) A clear correlation was observed between inoculation dose and mean time to death in the challenge system tested.
3) A satisfactory result was obtained in the experiment of drug efficacy, and the intramuscular inoculation was found applicable to tests for drug efficacy.
