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A 10-week-old female ferruginous hawk (Buteo regalis) was presented to the Kansas State University Veterinary Medical Teaching Hospital with a complaint of a 3-day history of lethargy and weight loss. The bird had been obtained from a nest in western Kansas for use as a falconry bird 5 weeks before presentation. Additional clinical signs the falconer noticed were weight loss, lethargy, and changes in behavior, including an unwillingness to step up on a gloved hand for food (despite an otherwise normal appetite), slight drooping of the wings, and decreased vocalizations. The bird was maintained in a partially enclosed 1.23 1.4-m building with multiple perches and a sand substrate. The bird’s diet consisted of frozen thawed adult mice; frozen thawed rabbit, beef liver, and raw chicken meat; and live prey, including quail, rats, and juvenile rabbits. Water was available ad libitum. On physical examination, the bird was in fair body condition (body condition score 2/5), weighed 1.4 kg, and had a slight bilaterally symmetrical wing droop. Immediately after the examination, the bird was allowed to perch and began staring at the wall (stargazing). This behavior had not been previously observed by the owner. Otherwise, the bird was alert and responsive with no overt neurologic deficits. A heparinized blood sample was obtained by right jugular venipuncture and submitted for complete blood count and plasma biochemical profile. A fecal flotation and wet mount were performed, and 2-view whole body radiographs were obtained with manual restraint (Figs 1 and 2). Results of the complete blood count revealed occasional reactive lymphocytes and marked toxic changes in the heterophils. Plasma biochemical values were unremarkable. Reference ranges were extrapolated from other raptor species. No ova or parasites were found on fecal examination.