Characterization of Sarcocystis falcatula isolates from the Argentinian opossum, Didelphis albiventris

Two isolates of Sarcocystis falcatula were obtained from the lungs of budge rigars (Melopsittacus undulatus) fed sporocysts from two naturally-infected South American opossums (Didelphis albiventris). The two isolates were des ignated SF-1A and SF-2A. Both isolates induced fatal infections in budgerig ars. Both isolates underwent schizogony in African green monkey kidney cell s. The structure of schizonts in the lungs of budgerigars was more variable than that observed in cell culture. The two isolates were identified as S. falcatula by the two species-specific Hinf 1 restriction fragments dervied from digestion of a PCR amplification using primers JNB33/JNB54. Thus, the South American opossum. D. albiventris, is a definitive host for S. falcat ula.