Publications

MERTHIOLATE has been used as a disinfecting agent for green and eyed eggs of various species (Gee and Sarles 1942, Snieszko and Friddle 1948). The present report is a description of the effects of the chemical on green eggs of the chinook salmon (Oncorhynchus tshawytscha). The need for this study was indicated when a program of transporting green chinook eggs from various sources to the...

No abstract available.

Intraspecific differences in erythrocyte antigens (blood types) were shown to occur in four species of Pacific salmon, the sockeye or red salmon (Oncorhynchus nerka), the chinook or king salmon (0. tshawytscha), the chum salmon (O. keta), and the pink salmon (O. gorbuscha). Antisalmon-erythrocyte sera prepared in rabbits and chickens were used after absorption of species-specific...

The nematode parasite Anisakis sp. can be recovered, relatively unaltered, from chum salmon musculature by high temperature (52°+2°C.) peptic digestion of the flesh. The procedure, which is presented in detail, appears to be more thorough in isolating the parasite than dissection of the flesh and manual isolation of the worms. In addition, the procedure is rapid, comparatively simple...

Consideration is given to a recurring disease of early feeding chinook salmon fingerlings at the Coleman, California, Federal Fish Cultural Station. The infection becomes manifest in the early spring months at low water temperatures and abates as the water temperature rises. Bacteriological studies have failed to yield the presence of a disease agent, either by cultural or staining...

The presence of mycobacteria in salmonoid fishes was first recorded by Earp, Ellis, and Ordal (1) in 1953. Acid-fast bacilli had previously been reported from other cold-blooded animals including fishes of fresh-water and marine origin; recent reviews have been presented by Vogel (2) and Parisot (3). The initiation of an intensive search for bacteria of this group revealed their...

FISH-CULTURISTs, in general, do not agree as to the time of actual fertilization of artificially spawned salmonid eggs. Some fish-culturists believe that the eggs are fertilized in the milt before water is added, while others are equally certain that fertilization is not achieved until after water is added. This difference of opinion has probably existed since the advent of the dry...

The pepsin-HCl digestion technique is probably the best method of isolating Anisakislarvae from the musculature of chum salmon. Some losses can be expected due to breakage of the resistant cuticle of Anisakis, and can be estimated to be about 6% when counting the parasites with the unaided eye. Comparisons of Anisakis infections of the dorsal and ventral musculature indicated that very...

On May 26, 1959, two of the authors' investigated a fish kill at Dailey Lake, Park County, Montana. They observed about a half-dozen live, weakly swimming yellow perch (Perca flavescens), in addition to thousand of dead perch along the shoreline. It was learned from local residents that mortalities had begun to appear some 2 weeks earlier. At that time the time the authorities had...

In a study of coho salmon (Oncorhynchus kisutch), the gross chemical and histological changes occurring over a 14-month period spent in fresh water were determined. The determinations were made at 3-month intervals on: 1) hatchery-reared fish, 2) fish hatchery-reared for 3, 6, 9, and 12 months and then planted in a controlled stream for the remainder of the period; and 3) an indigenous...

Epizootics among chinook salmon fingerlings at the Coleman National Fish Hatchery have occurred periodically since 1941. A virus or virus-like filterable agent has been demonstrated to be the causative agent of this disease.

No abstract available