84 American Fisheries Society. 



Dr. Moore: Yes. And a brush for every trough is even better. 

 This routine is very hard to establish as we find and as you w^ill find, 

 no doubt. When the hatchery laborer has learned the various mechani- 

 cal operations and works efficiently and swiftly in cleansing one 

 trough after another keeping the same brush in hand, it is hard to 

 divert him from that routine. Even though you bring him to the 

 microscope and show him the organisms in all their stages and indicate 

 how infectious they are, it is dift'icult to impress upon him the greater 

 need of thorough sterilization methods. Everything that helps to re- 

 duce the spread of infection must be resorted to in keeping the disease in 

 check. The use of separate utensils and frequently scalding them must 

 in the long run be efficacious. Heat kills readily most pathologic 

 organisms of the fish. A fortunate circumstance, since otherwise we 

 should not enjoy fish in our diet as much as we do. 



Mr. Adams: For the purposes of record, that the men in our hatch- 

 ries, that is, the young fish culturists, can get it, will you describe brief- 

 ly the exterior appearances or symptoms of octomitiasis? 



Dr. Moore: I have been thinking a good deal about how "to put 

 it over" to our hatchery men that they may recognize the disease and 

 deal with it early. Briefly the symptoms may be described as follows: 

 as observed in the troughs, badly infected fingerlings have a character- 

 istic behavior. Balance seems easily lost and they flop from side to 

 side, or roll over repeatedly with a "whirling" or "corkscrew" motion. 

 They appear to "bore" into the water. Just before death they lie on 

 their back with gills distended and in feverish action. Those greatly 

 weakened by disease and dwai'fish in size congregate in the corners at 

 the lower end of the trough, or nose along the sides, keeping near the 

 surface. The fish usually die on the screen or nearby at the foot of the 

 trouG-h. Sick fish removed from the water will give more specific 

 diarrhoeal symptoms and pass a yellowish, watery fluid on the slightest 

 pressure. In the troughs the superabundance of excrement in partial 

 stages of digestion is noticeable also. Of course in other diseases afflic- 

 ted fish may turn on their backs and have difficulty in breathing; that is, 

 they may show a similar "gill trouble" and emaciated ones may con- 

 gregate in the corners, but, if all the symptoms taken as a whole appear, 

 it is a pretty sure indication that octomitiasis is present. The symptoms 

 of a disease in which lesions occur internally should be supplemented by 

 microscopic examination. 



Mr. Adams: Are there no external marks on the fish? 



Dr. Moore: Generally there are not. I strongly suspect, however, 

 that the red spotting I have previously described as due to a congestion 

 of the blood beneath the skin is an occasional manifestation of the 

 disease. 



Mr. Adams: Side by side with that explanation, will you briefly 

 put into record a description of furunculosis? 



Dr. Moore: In the literature we find furunculosis described by the 

 German pathologists as an infectious disease of adult and yearling trout. 



