Development and line structure of intracytoplasmic and epicytoplasmic meronts, merozoites and young macrogamonts of the cichlid fish swim bladder coccidium Goussia cichlidarum

Abstract

Prior to becoming epicytoplasmic, meronts and gamonts were intracytoplasmic, within the swim bladder epithelium. We describe the fine structure of free merozoites; merozoites in endodyogeny; intracytoplasmic young meronts and macrogamonts; and epicytoplasmic young, mature and dividing meronts, merozoites, and early-stage macrogamonts.

Ultrastructural and developmental affinities of piscine coccidia

“…15) prior to their differentiation into meronts (Paperna 1991, Kim & Paperna 1992, Morrison et al 1993a. Endodyogeny also takes place in trophozoites of Goussia cichlidarum before, or as soon as, they enter the swimbladder (Kim & Paperna 1993a). In Eimeria vanasi also merozoites enclosed wi.thin macrophages in the lamina propria undergo endodyogeny.…”

“…Among all the ultrastructurally studied piscine coccidia to date, endomerogony, or rather endopolygeny, is the only demonstrated form of merogony in Epieimeria anguillae, Goussia aculeati, G. carpelli (Steinhagen 1991a) and G. cichlidarum (Kim & Paperna 1993a). In G. iroquoina, ectomerogony occurs prior to subsequent generations of endornerogony (Paterson & Desser 1981a).…”

“…Ultrastructural data are now available from several extraintestinal species: Calyptospora Eunduli (Hawluns et al 1983a(Hawluns et al , b, 1984, Goussia clupearum (Morrison & Hawkins 1984), infecting hepatocytes; Eimeria sardinae infecting testes (Morrison & Hawkins 1984); G. spraguei (Morrison & Poynton 1989) and a n undescribed species (Lukes 1993) infecting the kidneys; G. cichlidarum infecting the swimbladder epithelium , Kim & Paperna 1993a and G. gadi infecting the swimbladder's loose connective tissue (Morrison et al 1993a, b).…”

“…It is also common among intestinal species (Dykova & Lom 1981). In Goussia cichlidarum and G. gadi sporozoites or trophozoites, free or within macrophages, reach the swimbladder via the bloodstream, and in G. cichlidarum, via the rete mirabilis into the lining epithelium (Kim & Paperna 1993a, Morrison et al 1993a). In G. subepithelialis, sexudi bidyes spledci, ciuliily the iioriiial coiirse of i~fectiori, from the gut epithelium into the lamina propria (Steinhagen et al 1990).…”

Isolation and Characterization of Some Pathogenic Agents Causing Wobbling Syndrome in Cultured Oreochromis niloticus

“…Positive impression smears from gas bladder for coccidian oocysts were air-dried, fixed in absolute methanol and stained for one hour with a pH 6.8-buffered 10% Giemsa solution for further identification by the morphometry of the isolated parasite according to Kim and Paperna (1993).…”