communication, Branch of Fish Hatcheries, 

 Bureau of Sport Fisheries and Wildlife, 1962) 

 that during the 1961 and 1962 spawning seasons , 

 a very noticeable decline occurred in the 

 number of fall Chinook adults with underdevel- 

 oped ovaries. In previous years there were 

 many of these abnormal fish and nearly all of 

 them were heavily infected with mycobacteria . 

 However, this general reduction in infection 

 occurred in the absence of any major change 

 in diets fed at hatcheries on the Lower Colum- 

 bia River. 



Table 1: -Degree and incidence of acid-fast bacilli infections in adult male and female salmon 



collected at random at National Fish Hatcheries in Washington, Oregon, and California in 1958. 



Literature cited 



Ross, A. J., B. J. Earp, and J. W. Wood. 

 1959. Mycobacterial infections in adult 

 salmon and steelhead trout returning 

 to the Columbia River Basin and other 

 areas in 1957. U.S. Fish and Wild- 

 life Service, Special Scientific 

 Report- -Fisheries No. 462. 



Table 2: — Degree of incidence of acid-fast bacilli infections in adult male and female salmon collected 

 at random at National Fish Hatcheries in Washington, Oregon, and California in 1959. 



