Caracterização dos oocistos de Tyzzeria parvula (Kótlan, 1933) Klimes, 1963 (Apicomplexa: Eimeriidae) do ganso doméstico (Anser anser) no Brasil

Abstract

The principal objective of this research was to describe an coccidium found in the feces of greylag goose Anser anser Linnaeus, 1758. Based on morphometric analysis of these sporulated oocysts, they were classified as Tyzzeria parvula (Kótlan, 1933) Klimes, 1963. This coccidium was described for the firt time in goose of Brazil at rural and urban areas from the State of Rio de Janeiro. The oocysts were sub-spherical to ellipsoidal, measuring 11.28 to 16.44 for 9.15 to 14.44μm, with double-layer and without micropile, polar granule and sporocysts. The residuum was observed around the sporozoites or forming a granular mass. Eigth sporozoites were presents with one of the extremities rounded, and other one narrows and lightly curved. The sensitivity test in Cairina moschata and Anas platyrhynchos was done, however T. parvula did not develop infection. Through the comparison of the sporulated oocysts from goose of the rural and urban areas of the state of the Rio de Janeiro, it could be concluded that influences of the breeding systems and continuous natural infection degree in the greylag goose (A. anser) were responsible for pleomorphism of the dimensions of the T. parvula sporulated oocysts found in the feces of domestic goose of Brazil.