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FISH HATCHKRY MANAGEMENT 



Figure 81. Enteric red mouth disease in a rainbow trout. Note hemorrhaging in 

 eye and multiple petechial hemorrhages in liver. The spleen is swollen and a yel- 

 lowish mucoid plug has been pushed from the intestine. Judged by the pale gills 

 and watery blood in the body cavity, this fish was anemic. (Courtesy Charlie E. 

 Smith, FWS, Bozeman, Montana.) 



can be made only if the causative agent is isolated and identified. A tenta- 

 tive diagnosis based only on visible signs can be confused with other simi- 

 lar diseases (Figure 82). 



When present, the most common signs of MAS are superficial circular or 

 irregular grayish-red ulcerations, with inflammation and erosion in and 



Figure H2. Bacterial septicemia on a goldfish, caused by an infection with Aero- 

 monas hydrophila. (Courtesy National Fish Health Laboratory, Leewtown, West 

 Virginia. 



