Plasmodium circumflexum: age as a factor in isodiagnosis in Anatidae.
D000367:Age Factors; D000818:Animals; D004372:Ducks / Q000469:parasitology*; D004912:Erythrocytes / Q000469:parasitology; D008289:Malaria, Avian / Q000175:diagnosis*; D010961:Plasmodium / Q000302:isolation & purification