Publications

After the completion of the eхреriments reported recently, in which the efficacy of formalin in controlling infections of Gostia mecatrix was demonstrated, the author was afforded an opportunity to test the value of formalin solutions in combatting established mixed infections of (Gyrodactylus, Tricbodina, Cyclochaeta) and a stalked protozoan on rainbow trout fingerlings. This...

No parasite common to hatchery salmon and trout possesses quite so varied a reputation as does Octomitus salmonis. Discovered, studied, and described independently, but essentially simultaneously, by Dr. Emmeline Moore and Dr. H. S. Davis, Octomitus salmonis was introduced to fish culture during the early twenties. This easily found and widely distributed parasite, once recognized, was...

The smallest and most destructive of the ectoparasitic protozoans infecting salmon and trout, Costia necatrix, has unfortunately been relegated to virtual obscurity during the past few years. Few references to this parasite can be found in the recent literature and, where such things are discussed, one seldom hears a mention of Costia necatrix. This apparent lack of interest in Costia...

The prevention or control of epidemics of fish diseases by applying a disinfecting solution in a uniform concentration directly to the water supply of a fish pond or trough for a definite period of time has been exceedingly slow in development. In so far as can be determined, the original idea should be credited to. Marsh and Robinson (1910). In their work on the control of algae in fish...

The question has sometimes been raised whether or not any permanent injury may be inflicted upon fish eggs through their subjection to the relatively low temperatures prevailing in egg cases during shipment. This question may be argued in either direction purely upon the basis of indirect evidence which can be summoned in support of either contention. In so far as is known, this question...

A largemouth black bass fingerling preserved in formalin was sent to the U.S. Bureau of Fisheries Pathology Laboratory at Seattle, Washington, during the autumn of 1937, by a hatchery employee at Miles City, Montana. The fish exhibited several wart-like protuberances on the caudal peduncle, which aroused the curiosity of Mr. H. C. Topel, in charge of fish distribution at Miles City. He...

With the comparatively recent evolution of fish hatching into true fish culture the problems offered by fish disease have likewise evolved from more or less of a petty annoyance into a first class headache.

Henneguya salminicola was described in 1919 by Dr. H. B. Ward from cysts found in the body musculature of a silver salmon (Oncorhynchus kisutch Walbaum) taken from the Stickeen River in southeastern Alaska. Ward described the cysts as “pyriform, fairly uniform in size, and hard to the touch. . . . The cysts measured 3 to 6 mm in diameter and were found everywhere through the muscle mass...

For some very strange reason it is easy to minimize the villian's role, played by disease-producing organisms, in the theater of modern fish culture. Much concern is felt over the food bills footed each month by the hatcheries, but very little is thought about the dead fish which are picked from the hatchery troughs during the same period.

Furunculosis, or as it has been more appropiately termed, "fish septicemia," is a disease primarily affecting salmon and trout. It is caused by the invasion and growth of Bacterium salmonicida Emmerich and Weibel, a Gram negative, non-spore forming, diplobacterium belonging to the family Bacteriaceae Cohn. After gaining entrance to the host, presumably by way of the digestive tract, the...

Just where true fish culture appeared in history depends entirely upon what one considers fish culture to be. If the transportation of fishes from regions of plenty to those of few is to be regarded as fish culture - as it is by some even today - then this story should start in remotest antiquity and deal with an amazing series of failures. However, fish culture to be classed as a...

The first reference to a pathological condition of the gill tissues of salmonid fishes was made by Osburn in 1910. This author in describing a progressive infolding of the opercula of trout, commonly known to hatcherymen as "short gill covers," mentioned a marked proliferation on the gill epithelium as accompanying this condition. Osburn assumed that the club-like appearance of the gill...