Summary
The fine structural changes associated with first and second generation schizogony in Eimeria necatrix were studied in experimentally infected chickens. First-generation schizonts were found in crypt epithelial cells up to 48 hr postinfection, and second generation schizonts at 68 to 120 hr. The fine structural changes observed during development were similar in the first and second generations. Invaginations of the plasma membrane ramified in the cytoplasm and divided the multinucleated schizont of E. necatrix into several lobes prior to merozoite formation. Subsequently, merozoites began forming at the surface in association with nuclei and then grew outward from the schizont. An intranuclear spindle apparatus associated with a centrocone was frequently seen in schizont nuclei prior to and during the process of merozoite formation. Numerous infoldings of host membrane were found in the parasitophorous vacuole throughout schizogony. Enlargement of the parasitized host cell and its nucleus occurred during the growth of both first and second generation schizonts.
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Supported by the Ontario Ministry of Agriculture and Food.
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Fernando, M.A., Stockdale, P.H.G. Fine structural changes associated with schizogony in Eimeria necatrix . Z. Parasitenk. 43, 105–114 (1974). https://doi.org/10.1007/BF00329168
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DOI: https://doi.org/10.1007/BF00329168