Polymorphism of Eimerian Oocysts: A Dilemma Posed by Working with Some Naturally Infected Hosts

Authors

Brent B. Parker, University of New Mexico
Donald W. Duszynski, University of New MexicoFollow

Date of this Version

1986

Citation

Journal of Parasitology (1986) 72(4): 602-604.

Comments

Copyright 1986, American Society of Parasitologists. Used by permission.

Abstract

First paragraph:

Morphological variation of sporulated oocysts within individual eimerian species is well documented (Joyner, 1982. In Biology of the Coccidia, P. L. Long (editor). University Park Press, Baltimore, pages 35-62). In some cases, oocysts of a single eimerian species are known to vary in size by as much as 40% during patency (Duszynski, 1971, Journal of Parasitology 57: 948- 952). During a survey to determine the prevalence of coccidiosis in sandhill cranes (Grus canadensis) wintering in New Mexico (Parker and Duszynski, 1986, Journal of Wildlife Diseases 21: 25-35), marked polymorphism was observed among sporulated oocysts of Eimeria reichenowi. Oocysts were obtained from intestinal contents of cranes necropsied in the field and processed for study by routine sporulation and flotation techniques (Duszynski et al., 1982, Journal of Parasitology 68: 1146-1148). Initially, oocysts were categorized into five groups based on obvious qualitative/quantitative features including oocyst wall texture, appearance of the sporocyst residuum, and the number of polar bodies (Table I, Figures 1-6). Fifty-seven of 118 (48%) fecal samples with E. reichenowi contained two or more morphological types of oocysts. Oocysts were measured under oil immersion (100 x Neofluar objective, Zeiss Universal Photomicroscope) and differences between the five oocyst groups were tested for significance (P < 0.05) using the Student-Newman-Keuls procedure.