The Disinfection of Trout Eggs Contaminated with Bacterium Salmonicida.

"Furunculosis," a highly infectious disease of the Salmonidae caused by Bacterium salmonicida Lehmann and Neumann (Emmerich and Weibel, 1894; Lehmann and Neumann, 1920; Marsh, 1902; Williamson, 1928; Mackie, et al., 1930; Duff and Stewart, 1933; Fish, 1937), received its name from the boillike lesions that occur in the musculature of the infected fish. The "furuncles'" often break through the skin, discharging a red, pus-like material consisting of bacteria, blood corpuscles, and disintegrated muscle tissue. The lesion is not, strictly speaking, a furuncle or boil since there is no accumulation of white corpuscles at the focus of infection; nor is there any protective tissue reaction, such as characterizes the furuncle in higher animals. The term "furunculosis't has been used to designate this disease by numerous investigators over a period of years, and hence is of sufficient specificity to characterize this pathological condition. Mackie, et al., (1930) isolated Bacterium salmonicida from the ripe ovaries of experimentally infected fish, and Smith (1939) isolated this bacterium from the shell of trout eggs. Plehn (1911), Williamson (1929), and Mackie, et al., (1930) failed to find B. salmonicida inside trout eggs. It is concluded, therefore, that the eggs serve as mechanical carriers, and that the bacteria are found only on, not in the egg. Transfer of contaminated eggs is one of the ways by which furunculosis spreads. The disinfection of contaminated eggs prevents epidemics of the disease in hatcheries. Blake (1930), working for the British Furunculosis Committee, found that phenol and brilliant green harmed fertile trout ova when applied in strengths necessary to destroy B. salmonicida; that potassium permanganate and chlorine were comparatively non-injurious in such concentrations, but were useless in the presence of minute quantities of organic matter; that acriflavine is a suitable disinfectant for contaminated trout eggs. She states, "At a concentration of 1 to 2000, this substance destroys Bacterium salmonicida and is practically non-