Glochidiosis of Salmonid Fishes. II. Comparison of Tissue Response of Coho and Chinook Salmon to Experimental Infection with Margaritifera margaritifera (L.) (Pelecypoda: Margaritanidae)

Abstract

Coho salmon (Oncorhynchus kisutch) are more resistant to experimental infection with the glochidia of the freshwater mussel (Margaritifera margaritifera) than are chinook salmon (Oncorhynchus tshawytscha). Histological sections made at intervals during the infection showed that coho salmon sloughed the parasites from their gills by 4.5 days postinfection, but the parasites remained encysted in the gills of chinook salmon for 12 weeks, when metamorphosis to juvenile mussels was complete. Coho salmon sloughed the parasites by a well-developed hyperplasia. No such pronounced hyperplastic reaction was seen in the gills of chinook salmon.

Gill tissue reactions in walleye Stizostedion Vitreum vitreum and common carp Cyprinus carpio to glochidia of the freshwater mussel Lampsilis radiata siliquoidea

“…Eosinophilia is a common tissue response in vertebrates to metazoan parasites. As in our study, Arey (1932a) and Fustish & Millemann (1978) found fewer eosinophils in tissues surrounding glochidia in suitable than in unsuitable hosts.…”

“…The noncellular, necrotic inner zones of capsules in carp, pronounced hyperplasia in surrounding gill tissues, and the presence of eosinophilic granulocytes in capsules and surrounding tissues also may represent mechanisms for glochicial rejection. Fustish & Millemann (1978) reported that coho salmon infected with glochidia of M. margaritifera displayed a greater degree of hyperplasia associated with larger diameter capsules than was observed in the more suitable host chinook salmon 0. tshawytscha. Awakura (1968) reported that glochidia of Margaritifera laenis were destroyed by host tissue proliferation in immature Oncorhynchus masou, Salvelinus leucomaenis, and Salmo gairdneri.…”

Mast cells/eosinophilic granule cells of teleostean fish: a review focusing on staining properties and functional responses

“…Responses similar to those of salmonids, with local recruitment/accumulation of MCs/EGCs in parasiteinfected tissues have been demonstrated in catostomids (Chaicharn & MAST CELLS/EOSINOPHILIC GRANULE CELLS Bullock, 1967;Lester & Daniels, 1976), cyprinids (Percy, 1970Cross & Matthews, 1993 and labroids (Reimschuessel et al, 1987;Reite, 1996b). Thus, recruitment of MCs/EGCs to sites of persistent inflammation seems to be a general response in teleosts, and it should also be mentioned that fewer EGCs have been found in tissues surrounding freshwater mussel glochidia in unsuitable than in suitable hosts (Fustish & Millemann, 1978;Waller & Mitchell, 1989). The numerous eosinophils described to appear locally during inflammation and wound healing in the skin of the stickleback, Gasterosteus aculeatus (Phromsuthirak, 1977) and in inflammatory exudates in the peritoneal cavity of the striped bass, Morone saxatilis (Bodammer, 1986) and tilapia, Oreochromis nilotica (Suzuki, K., 1986) may also have been tissue EGCs, as may the ' eosinophils with coarse granules ' demonstrated by an early investigator (Drury, 1915) in the peritoneal fluid of several teleostean species.…”

Temporal and spatial distribution of glochidial larval stages of European unionid mussels (Mollusca: Unionidae) on host fishes

“…1). Only the left side of the gills was examined since no difference in the number of glochidia between the left and right side of the gill apparatus had been observed by previous authors (Paling 1968, Wootten 1974, Fustish and Millemann 1978, Cunjak and McGladdery 1991. The fins were divided into inner and marginal (fin edge) sections.…”