Disinfection of Hatchery Water Supply by Ultraviolet (U. V.) Irradiation-I
Susceptibility of Some Fish-Pathogenic Bacterium and Microorganisms Inhabiting Pond Waters.
1976 Volume 42 Issue 2 Pages 207-211
Details
1976 Volume 42 Issue 2 Pages 207-211
Basic experiments were carried out preliminarily to determine the usefulness of a double-tubular U. V.-water treatment unit (Seibu Kagaku Co., Model Cs-50 U) for the disinfection of hatchery water.
The results obtained are summarized as follows.
1. The disinfectant effect of U. V. was examined on cell suspensions (105-7cells/ml) of 5 species of fish pathogen and one strain of Escherichia coli. A 99.99%or more reduction of their viable cells was effected by U. V. treatment of less than 8.5l/min. flow rate that is equivalent to more than 22, 100μW⋅sec/cm2 U. V. dosages.
2. The experiments on 4 specimens of fish-rearing pind waters containing 104-6 viable cells/ml indicated that U.V. radiation is an effective means of destroying microorganisms in the hatchery water supply. However, a tendency towards U. V. resistance was shown by some groups of water microflora, e. g. Coryneforms, or yeastlike organisms.
