but it may be transmitted through the water. Subcutaneous injections 

 of bacteria are almost invariably fatal, but feeding either material from 

 the lesion or cultures of the bacteria causes few deaths. Evidently the 

 fish do not invariably acquire the disease when exposed to bacterial infec- 

 tion unless there is a local lesion or a point of lowered resistance. There- 

 fore, continued contact with diseased fish is an important means of spread- 

 ing the disease. The artificial condition of hatchery rearing favors the 

 tendency to keep the maximum number of fish per pool. The fish receive 

 unnatural food and do not get exercise as in nature. Thus, the chances 

 for catching the disease and the spreading of an epidemic are very much 

 greater among hatchery fish. The only practical treatment is radical 

 elimination by killing the infected and exposed fish and thoroughly steril- 

 izing the pools. Early diagnosis and prompt action are necessary to check 

 bacterial diseases. Radical methods offer the only efficient method of 

 handling such epidemic diseases. 



In hatchery work the prevention of disease, not the treatment of in- 

 dividual fish, is the prime essential, except in the case of valuable aqua- 

 rium fish. Mechanical or chemical methods of treatment are of little or 

 no value for the septicsemic diseases. "With the exception of the beneficial 

 effect upon Inngus of the salt, and possibly the mud. Iiath all the empiri- 

 cal methods handed down from the dark ages of fish culture are value- 

 less in combatting bacterial epidemics, and frequently do more harm than 

 good. In treating fish infected with Furunculosis, I have tried every 

 method I had ever heard of, and the untreated fish lived longer than the 

 treated, probably due to the additional handling. In my opinion, we havf 

 all been laboring under a delusion, as regards the eflSciency of the bath 

 and the chemical treatment of bacterial diseases of fish. 



Mr. J. W. TiTCOMB, Albany, N. Y. : Were the fish in water above the 

 pools? 



Db. Belding : They were in separate pools fed chiefly by springs, 

 but were unfortunately contaminated by implements used in the diseased 

 pools, a condition which could have been avoided if rigid isolation had 

 been enforced. To illustrate the practicability of absolute isolation in this 

 connection, it may be stated that this particular hatchery had two divi- 

 sions — one at Sandwich, and the other at East Sandwich — three miles 

 apart, and that, by instituting a rigid quarantine, the Sandwich division 

 was kept entirely free from disease. I believe we could have quarantined 

 those fingerlings, although it would be more difficult because of proximity, 

 seepage from contaminated ground, and fish-eating birds. This spring the 

 disease was checked by promptly destroying 600 fish in one pool where 

 infection was discovered. That is a debatable question. At the time, I 

 decided that it was better to kill the fish in order to keep Massachusetts 

 waters absolutely free from this disease. Since then, I have found dis- 

 eased wild fish, indicating that Massachusetts is not free from this par- 

 ticular disease, although possibly it is less prevalent than in New York, 

 New Jersey, and Pennsylvania. Now, I would be inclined to recommend 

 that these fish be put into some coastal streams of limited range and the 

 results watched. Of the 600 fish referred to probably less than 10 per 

 cent would be infected, and they would spread over a comparatively 

 wide territory. It is probable that the 10 per cent would die without 



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