Abstract: The degree of incidence of acid-fast bacillus infections in adult salmonid fishes was determined. The disease was shown to be widely distributed in the area examined. It is believed the primary source of infection is derived from the hatchery practice of feeding infected salmon products to juvenile fish. One group of marked adults that had been hatchery reared for 370 days showed a 62 percent incidence of infection. A statistical analysis indicated that length of fish is independent of infection.

Excerpt from Mycobacterial Infections in Adult Salmon and Steelhead Trout Returning to the Columbia River Basin and Other Areas in 1957 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. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

This Second Edition has been expanded to two volumes, the first of which focuses on marine fish. Volume 1 reviews the important diseases of wild, captive, or cultivated fish species, fish immunology, the effects of disease on populations, and public health aspects of fish diseases. Fishery scientists and managers, marine biologists, marine ecologists, and marine aquaculturists will find this volume indispensable. Principal Diseases of Marine Fish and Shellfish examines: Important diseases of marine fish and shellfish The effects of disease on wild and cultivated populations of fish and shellfish How fish and shellfish resist invasion by potential pathogen The influence of coastal/estuarine pollution on fish and shellfish disease The public health implications of fish and shellfish diseases

Incidence of acid-fast bacillus infections in salmonid fishes at West Coast hatcheries was determined for 1957-59. No evidence was obtained which would indicate a definite trend towards either increased or decreased rates of infection. It is apparent that the incidence of infection is higher in hatchery-marked fish than in unmarked fish. Only one hatchery was found free of infection during the 3 years covered by the investigation. This installation had never used raw salmon products in diet.