82 American Fisheries Society. 



Dr. Osburn: Might death be due to interference with digestion? 

 If there is a diseased area covering a large portion of the intestinal tract, 

 the result would be a lack of the absorption of food. But, if there were 

 any intense toxic effect, you would expect that death would come sooner. 



Dr. Moore: From the nature of the excretory products I should 

 say there must be more or less chronic indigestion. As to toxic effects 

 operating- in more rapid cause of death, I am unable to judge except by 

 inference. Some diseased fish, less emaciated than others succumb to 

 the disease quickly, the reason therefor may be a toxic effect due to a 

 condition favoring an excessively rapid production of the organisms. 



Dr. Osburn: How much of the intestine is affected? What por- 

 tions of the intestinal area might be sloughed off in the severer cases? 



Dr. Moore: The seat of infection is in the fore-intestine and ceca. 

 Other portions of the intestine are invaded by adults, but I am not yet 

 sure that the epithelial cells there are parasitized. Dr. Davis' findings 

 indicate that the parasitized tissue occurs only in the ceca and fore- 

 intestine. These seem to be the portions that easily slough away. It 

 is possible that there may be invasion of epithelial cells lower down in 

 the intestine in the severer cases of infection of larger fish. 



Mr. Titcomb: May I inquire whether the eggs of the fish carry 

 the organism? 



Dr. Moore: That seems a possibility from the fact that the organ- 

 ism is carried in the blood. 



Mr. Titcomb: It would be necessary to establish that if you are to 

 attribute the importation of the disease to the brown trout. 



Dr. Moore : Yes. I realize that, and that it will require much time 

 and exhaustive study and experimentation to establish the fact one way 

 or another. 



Mr. Titcomb: It would mean all those .states which are buying eggs 

 from infected commercial hatcheries are liable to introduce the disease. 



Dr. Moore: The disease is certainly very infectious and probably 

 no state in the East is free from it. 



Mr. Titcomb: The disappearance of the brook trout has in certain 

 cases been attributed to cannibalism of the brown trout. Do you think 

 that part of that disappearance of brook trout may be attributed to this 

 disease? 



Dr. Moore: It seems reasonable to think so, especially as our knowl- 

 edge of the feeding habits of the brown trout become better known. 

 It seems from the observation that the brown trout is more of a bottom 

 feeder than the brook trout. 



Mr. Titcomb: You have not found anything new in the way of a 

 remedy, or anything in the diet to regulate it. 



Dr. Moore: No. More perfect sterilization measures seem the only 

 hope at present. As to regulating the diet, I have not given any atten- 

 tion to that side of the problem. I understand that Dr. Davis of the 

 U. S. Bureau has been investigating that phase of the subject. 



