Location: Animal Parasitic Diseases LaboratoryTitle: Gametogony of Eimeria macusaniensis Guerro, Hernandez, Bazalar and Tabacchi, 1971 in Llama (Lama glama)
Submitted to: Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/3/2018
Publication Date: 4/12/2018
Citation: Dubey, J.P. 2018. Gametogony of Eimeria macusaniensis Guerro, Hernandez, Bazalar and Tabacchi, 1971 in Llama (Lama glama). Parasitology. 145:1540-1547. https://doi.org/10.1017/S0031182018000483.
Interpretive Summary: Toxoplasma, Neospora, Sarcocystis, Eimeria, and Cystoisopora are related coccidian parasites that cause severe illness in livestock. Oocyst is the environmentally resistant stage passed in feces of the definitive hosts. While Toxoplasma and Neospora have wide host range, Eimeria are generally host specific. Eimeria macusaniensis is a pathogenic coccidium of camelids and there are many reports of fatal coccidiosis in these hosts. The life cycle of this parasite is not fully known. In the present paper, Dubey describes details of development of E. macusaniensis in the small intestine of a llama (Lama glama). These results will be of interest to parasitologists and veterinarians in diagnosis of coccidiosis in camelids.
Technical Abstract: Camelids (llama, alpaca) are important for the economy of South America and Eimeria infections are an important cause of mortality in camelids. Of the five species of Eimeria in camelids, Eimeria macusaniensis, considered the most pathogenic, is distinctive; its oocysts are the largest among all Eimeria species in animals, its prepatent period is more than one month, and its oocysts have been found in mummies from prehistoric times. Although, E. macusaniensis gametogonic stages are found associated with enteritis in naturally infected camelids, the schizogonic stages are unknown and clinical disease has been reported in some camelids with no oocysts in feces. Described herein are morphological details of gametogonic development and oocyst formation of E. macusaniensis in a naturally infected llama (Lama lama), solely infected with this parasite. Microgamonts, macrogamonts, and oocysts were located in large (up to 300 µm diameter) parasitophorous vacuoles of enterocytes in the ileum. Schizonts were not found. Review of previous reports suggests that multinucleated microgamonts have been mistaken for schizonts. Gametogonic development described in the present study can serve as a guide for differential diagnosis of Eimeria species in histological sections of intestines.