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Joseph R. Uzmann

Publications and source records attributed to Joseph R. Uzmann.

5 recordsLinked to original sources

Rapid counting of nematoda in salmon by peptic digestion

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, economical, and suitable for the examination of large numbers of samples. The population of Anisakis sp ., larvae in chum salmon appears to be concentrated in the ventral section of the fish, that is, below the lateral line, which ಟ್ಗ that only the ventral quarters of the fish need to be examined for estimating infection intensity.

Special Scientific Report - Fisheries

The killifish, fundulus heteroclitus, second intermediate host of the trematode, Ascocotyle (Phagicola) dimunuta

Ascocotyle (Phagicola) diminuta was described by Stunkard and Haviland (1924)from the intestine of wild rats collected at the Clason Point dump near New York by the City Board of Health. Feeding experiments have demonstrated that metacercariae encysted in the gills of the common killifish, Fundulus hetero clitus , are stages in the life-cycle of this parasite. The larvae have been found also, although rarely and in small numbers, in the gills of the striped killifish, Fundulus majalis . Since both species of Fundulus are susceptible, it appears probable that the habits of F. heteroclitus occasion greater exposure of this species to the cercariae. It is possible that infection of the fishes occurs during the spawning season when they are in water of low salinity. The asexual stages of these trematodes and the mollusks which harbor them are yet unknown.

Biological Bulletin