Abstract
ABSTRACT. Teixeira Filho W.L., Cardozo S.V. & Lopes, C.W.G. [Viability and morphobiology of Cystoisospora ohioensis (Dubey, 1975) Frenkel, 1977 (Apicomplexa: Cystoisosporinae) oocysts shed by dogs experimentally infected] Viabilidade e morfobiologia dos oocistos de Cystoisospora ohioensis (Dubey, 1975) Frenkel, 1977 (Apicomplexa: Cystoisosporinae) eliminados por cães infectados experimentalmente. Revista Brasileira de Medicina Veterinária, 32(3):161-165, 2010. Escola de Ciências da Saúde, Curso de Ciências Biológicas, Universidade do Grande Rio, Rua Prof. José de Souza Herdy, 1160, Duque de Caxias, RJ 25071-202, Brasil. E-mail: sergianvc@oi.com.br With the purpose of estimating the viability, sporulation time, prepatent period (PPP), patent period (PP) and morphologic patterns of Cystoisospora ohioensis, dogs were divided in two groups and were infected with 5 x 104 sporulated oocysts, two of these were infected with stoked oocysts that were storage at refrigeration temperature for a period of two years, where were obtained first passing oocysts, were obtained by infection of two other animals. Then the total quantity of feces daily eliminated for each group, were submitted to forced aeration to obtain sporulated oocysts. The stoked oocysts had 23.82±0.98 by 21.24±1.65µm length and width respectively, whereas sporocysts measured 19.78±1.80 by 14.35±2.07µm of diameter. The first passing oocysts last twelve days to complete the sporulation, the PPP was three days and the PP was eight days. Oocysts were 26.17±2.66 by 23.23±2.67µm whereas sporocysts measured 16.43±2.50 by 12.67±1.67µm of diameter. The second passing oocysts had PPP of five days, PP of nineteen days and sporulated in six days, whereas oocysts and sporocysts measured 20.84±1.38 by 18.59±1.75µm and 13.61±1.25 by 9.59±0.90µm, respectively. Significant differences between PPP and PP were observed, and in the morphometry of the sporocysts from second passage with oocysts varying from subspherical to elliptical.