Survey of tank water and challenged fish faeces.
During the process of the challenge trial, water and
faeces samples were taken every day and subject to
bacterial isolation and enumeration as described by
Sakata & Kawazu (1990). Briefly, 3 water samples were
collected per tank (10 ml), and faeces were collected
via a fine mesh net and re-suspended in 10 ml of sterile
PBS. Successive serial 10-fold dilutions of the samples
were performed and 0.1 ml from each of the dilutions
was spread on the agar plates.