P. Torres et al., PREVALENCE AND PATHOLOGICAL ASPECTS TO DI PHYLLOBOTHRIASIS IN RETURNING SALMON, ONCORHYNCHUS-KISUTCH, TO COYHAIQUE, 11TH REGION, CHILE, Archivos de medicina veterinaria, 27(1), 1995, pp. 107-114
The presence of plerocercoids of Diphyllobothrium sp. in salmon return
ing from the ocean to Coyhaique (45-degrees-35'S, 72-degrees-07'W), Ch
ile, are reported for the first time. Twenty-one out of 30 adult fish
examined were parasited with plerocercoids. Morphological characterist
ics are similar to Diphyllobothrium pacificum, a common zoonotic paras
ite in Chilean and Peruvian marine fish. Experimental infection in def
initive hosts such as dogs, is necessary in order to identify the para
site to a specific level. Plerocercoids in the mucosa, muscular layers
and serosa of stomach induced moderate vacuolar degeneration. An incr
ease in the number of granular eosinophilic cells of the compact strat
um was observed in muscular layers and in the corion of the mucosa ass
ociated to plerocercoids; all surrounded by a fibroblastic reaction. A
rterial vessels presented hypertrophia of the muscular layer and degen
erative injury of endothelial cells, with citoplasmatic vacuolization.