CONTENTS 



Page 



Mycobacteria in adult salmonid fishes returning 



to Federal hatcheries in Washington, Oregon and 



California, by A . John Ross 1 



Mycobacteria in adult salmonid fishes returning 



to State hatcheries in Washington, by Brian J. Earp 10 



Addendum 13 



A survey of tuberculosis in Pacific salmon and 

 steelhead trout in Oregon streams in 1957, by 

 James W . Wood 18 



INTRODUCTION 



A survey of the diseases of Columbia River salmon and steelhead trout was 

 initiated in 1957 in joint recognition that fish diseases are a major factor influenc- 

 ing the successful maintenance and rehabilitation of salmon and steelhead populations 

 in the Columbia River Basin and neighboring regions. Agency responsibility was 

 delineated and contracts for the work let by the U.S. Fish and Wildlife Service to 

 the Washington Department of Fisheries and Oregon Fish Commission. 



Initial studies were Limited to an appraisal of the geographical distribution 

 incidence, and intensity of the disease agent responsible for the tuberculosis -like 

 infection of salmonid fishes. It was deemed that an understanding of the infection 

 would guide management practices with subsequent control of the infection substan- 

 tially reducing losses in salmon and steelhead populations. 



Each of the participating agencies compiled the results of its 1957-1958 study 

 in a manner most appropriate to the data obtained. The reports of each agency are 

 presented here as submitted. 



