Studies on Amyloodinium ocellatum (Dinoflagellata) in Mississippi Sound: Natural and Experimental Hosts

摘要: Four species of parasitic dinoflagellates have been found to occur naturally on the gills and fins Mississippi Sound fishes: Amyloodinium ocellatum (Brown 1931) Brown Hovasse 1946, Oodinium cyprinodontum Lawler 1967, two undescribed species. Sixteen 43 fishes examined had natural gill infections A. ocellatum. Seventy-one 79 exposed dinospores were susceptible, succumbed, dinoflagellate. Eight did not die even though numerous dinospores. The most common signs in an infested fish spasmodic gasping uncoordinated movements. Trophonts gills, skin, fins, eyes, pseudobranchs, membranes branchial cavity around teeth; lateral line pits, nasal passages, esophagus, intestine experimentally infected fishes. dinoflagellate causes extensive mortalities held under closed-system mariculture conditions. INTRODUCTION Parasitic first reported from vertebrates by (1931), who described (= Amyloodinium) marine aquarium Additional references this are those (1934), Nigrelli (1936, 1939, 1940), (1946), Chatton (1952), Porter Dempster (1955, 1956, 1972), Laird (1956), Simkatis (1958), Hdjgaard (1 962), Paccaud Chlupaty (1962), Buxton Graaf Valenti (1968), Kingsford (1975), Becker (1977), (1977a, 1977b, 1979). limneticum, a freshwater fishes, was Jacobs (1946); additional Kozloff (1948, 1949), Patterson (1949), Lewis (1963). Another species, 0. pillularis Schiiperclaus, 1954, has received considerable attention Europe (Weiser 1949; Schiiperclaus 195 1 ; Hirschmann Partsch 1953; Reichenbach-Klinke 1955, 1961; Schubert 1959; Geus, 1960a, 1960b, 1960c , 9 6 0 d Elkan 1965; Lucky 1970. An estuarine cyprinodontum, Virginia cyprinodontids (1967). It Dillon (1966), (1967, 1968a, 1968b), Lom (1971, 1973), Williams (1972). Of these only North America. Unidentified American Overstreet Papema Zwerner (1976). Gulf Mexico (Williams 1972); (1975) illustrated trophont mangrove snapper (Lutjanus griseus) with infection, presumably eastern Mexico. 'This study conducted part cooperation U.S. Department Commerce, NOAA, National Marine Fisheries Service, PL 18-309, Roject No. 2-262-R. Manuscript August 1979; accepted October 10,1979. 193 1) confined areas 1931, 1934; 1936, 1940; H$jgaard 1962; 1977a, 1977b), many teleosts 1946; 1956; Straughan 1970; 1967 yet cause deaths aquaria (Lawler, unpublished). In 1971, I started trying control Micropogonias undulatus which being for experiments lymphocystis (Cook 1972). Studies initiated ascertain following: (1) identity present Sound; (2) hosts waters; (3) susceptible aquaria; (4) methods controlling trophonts aquaria. report includes my findings thus far three items. results efforts parasites will be presented future report. MATERIALS AND METHODS Fishes collected mainly Sound, Biloxi Bay Horn Island, means trawls, traps, dip nets, hook line. Salinity determined refractometer. alive water their place capture within day. bled gutting them or cutting tail draw blood away as, facilitating examination excised reflected light dissecting microscope. gdls autoclaved seawater avoid introduction fortuitous dinoflagellates. Infected filaments removed irridectory scissors live compound microscope presence stigma, stomopode, other morphological characters. 403