RESUMEN
An outbreak of coccidiosis by Isospora icterus (I. icterus, Upton & Whitaker, 2000) in captive Campo Troupial (Icterus jamacaii) (Gmelin, 1788) at the Wild Animals Triage Center (IBAMA, Belo Horizonte, Brazil) is described. Clinical history and the necropsy findings documented diarrhea with diffuse necrotic enteritis. Sporulated oocysts (n = 100) had a bilayered wall, were subspherical, and measured 30.1 (27.5-32.5) microm in length and 28.5 (26.2-30.0) microm in width. A polar body but no micropyle was present and the length/width ratio was 1.1 (1.00-1.2). Each oocyst contained two ellipsoidal sporocysts measuring 17.6 (15.0-20.0) microm in length and 12.9 (12.5-15.0) microm in width, with a length/width ratio of 1.4 (1.2-1.5), and with Stieda and sub-Stieda bodies. Each sporocyst contained four sporozoites with granular sporocyst residuum. Oocysts were compatible with those from I. icterus, previously described in Campo Troupial.