This study reports two clinical cases of avian haemosporidian infection caused by a Haemoproteus sp., involving a snowy owl (Bubo scandiacus) and a goshawk (Accipiter gentilis), at a zoo. The snowy owl died after presenting with anorexia, depression and lethargy. A blood smear with Wright’s staining confirmed Haemoproteus infection. Necropsy of the snowy owl revealed hypertrophy of the internal organs, including the liver, gallbladder, kidney and adrenal glands. The goshawk showed anorexia, depression and a lowered head position, and was diagnosed with a Haemoproteus infection based on a blood smear. The goshawk was completely cured by treatment with a combination of atovaquone and proguanil hydrochloride. Both cases showed decreased erythrocytes, hemoglobin and hematocrit values on complete blood count.

A captive 4-year-old female red-crowned parakeet (Cyanoramphus novaezelandiae) presented with anorexia, diminished activity and thick, beige, crusted lesions over the cere, legs, wings and cloaca. Deep skin scrapings from various lesions identified Knemidokoptes pilae as the causative agent. For treatment, the crusts were debrided, and the lesions were topically treated with ivermectin, chlorhexidine and silver sulfadiazine. The parakeet died the day after treatment. Previous studies examining K. pilae have focused primarily on the morphologic characteristics of adult female mites. This study presents a more comprehensive morphologic analysis, with examination of K. pilae at different stages of development (eggs, larvae and adult males and females).