Cell cultures of embryonic bovine liver, lamb kidney, whole ground-squirrel embryos and adult Madin-Darby bovine kidney were used to study the in vitro development of Eimeria larimerensis from the Uinta ground-squirrel, Spermophilus armatus. Leighton tubes were inoculated with sporozoites and the monolayers were examined with phase-contrast microscopy at various intervals; fixed and stained material also was studied. In all cell types, sporozoites penetrated and developed to trinucleate second-generation schizonts. The intracellular sporozoites increased in size and underwent nuclear divisions. The sporozoite-shaped schizonts had motility similar to that of the sporozoites. After the formation of 4–10 nuclei, transformation from the sporozoite-shaped schizont to a spheroidal schizont occurred by a lateral outpocketing in the anterior region or a progressive increase in width of the body. In 10 specimens, completion of the transformation process at 37 C required an average of 57 min. The greatest numbers of spheroidal schizonts were seen at 48 hr. Merozoites were apparently formed by a radial budding process, which required an average of 72 min at 37 C. The largest numbers of mature first-generation schizonts were seen at 60 hr after inoculation; these had 4–36 merozoites. Each merozoite had anterior and posterior refractile bodies; some also had small posterior refractile granules. The refractile bodies of the merozoite were derived from the posterior refractile body of the sporozoite. Second-generation trophozoites were seen at 60 hr, and second-generation bi- and trinucleate schizonts were seen at 60 and 72 hr after inoculation.
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Chobotar, B., Hammond, D. M., Miner, M. L.: Development of the first-generation schizonts of Eimeria auburnensis. J. Parasit. 55, 385–397 (1969).
Clark, W., Hammond, D. M.: Development of Eimeria auburnensis in cell cultures. J. Protozool. 16, 646–654 (1969).
Fayer, R.: Refractile body changes in sporozoites of poultry coccidia in cell culture. Proc. Helminth. Soc. Wash. 36, 224–231 (1969).
— Hammond, D. M.: Development of first-generation schizonts of Eimeria bovis in cultured bovine cells. J. Protozool. 14, 764–772 (1967).
— Morphological changes in Eimeria bovis sporozoites during their first day in cultured mammalian cells. J. Parasit. 55, 398–401 (1969).
Hammond, D. M., Ernst, J. V., Miner, M. L.: The development of first-generation schizonts of Eimeria bovis. J. Protozool. 13, 559–564 (1966).
— Fayer, R.: Cultivation of Eimeria bovis in three established cell lines and in bovine tracheal cell line cultures. J. Parasit. 54, 559–568 (1968).
— Speer, C. A., Roberts, W.: Occurrence of refractile bodies in merozoites of Eimeria species. J. Parasit. 56, 189–191 (1970).
Kelley, G. L., Hammond, D. M.: Development of Eimeria ninakohlyakimovae from sheep in cell cultures. J. Protozool. 17, 340–349 (1970).
Parker, R. C.: Methods of tissue culture, 3rd ed., p. 145–151. New York: Paul B. Hoeber, Inc., 1961.
Roberts, W. L., Hammond, D. M., Anderson, L. C., Speer, C. A.: Ultrastructural study of schizogony in Eimeria callospermophili. J. Protozool. 17 (1970).
Sheffield, H. G., Hammond, D. M.: Electron microscope observations on the development of first-generation merozoites of Eimeria bovis. J. Parasit. 53, 831–840 (1967).
Speer, C. A., Hammond, D. M.: Nuclear divisions and refractile body changes in sporozoites and schizonts of Eimeria callospermophili in cultured cells. J. Parasit. 56, 461–467 (1970).
— Anderson, L. C.: Development of Eimeria callospermophili and E. bilamellata from the Uinta ground-squirred Spermophilus armatus in cultured cells. J. Protozool. 17, 274–284 (1970).
Todd, K. S., Jr., Hammond, D. M.: Life cycle and host specificity of Eimeria callospermophili Henry, 1932 from the Uinta ground-squirrel Spermophilus armatus. J. Protozool. 15, 1–8 (1968a).
— Life cycle and host specificity of Eimeria larimerensis Vetterling, 1964, from the Uinta ground-squirrel Spermophilus armatus. J. Protozool. 15, 168–175 (1968b).
— Anderson, L. C.: Observations on the life cycle of Eimeria bilamellata Henry, 1932 in the Uinta ground-squirrel Spermophilus armatus. J. Protozool. 15, 732–740 (1968).
Wagner, W. H., Foerster, O.: Die PAS-AO-Methode, eine Spezialfärbung für Coccidien im Gewebe. Z. Parasitenk. 25, 28–48 (1964).
Supported in part by research grant AI-07488 from the NIAID U.S. Public Health Service. Published as Journal Paper No. 1044, Utah Agricultural Experiment Station.
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Speer, C.A., Hammond, D.M. Development of Eimeria larimerensis from the Uinta ground-squirrel in cell cultures. Z. F. Parasitenkunde 35, 105–118 (1970). https://doi.org/10.1007/BF00259988
- Cell Culture
- Progressive Increase
- Transformation Process
- Anterior Region
- Nuclear Division