Hypothyroidism in a scarlet macaw.
A diagnosis of hypothyroidism was confirmed by use of thyrotropin stimulation testing in an imported male scarlet macaw. Clinical signs included delayed molt; uniform, diffuse contour feather loss over the entire body; and excessive fat deposition over the legs and ventral portion of the abdomen. Clinical signs were associated with mild, non-regenerative anemia; mild leukocytosis; heterophilia; hypoalbuminemia; and hypercholesterolemia. Histologic examination of punch biopsy specimens from regions of feather loss revealed ortho- and parakeratotic hyperkeratosis of the epidermis and moderate, widespread vacuolar degeneration and necrosis in the follicular epithelium. The bird failed to respond to provocative thyrotropin stimulation testing. Treatment with L-thyroxine (0.2 micrograms/kg of body weight, q 12 h) resulted in normal feathering, elimination of fat deposits, and adequate serum thyroxine concentrations at 4 and 12 hours after treatment.
Oglesbee
B L
BL
Department of Clinical Sciences, College of Veterinary Medicine, Ohio State University, Columbus 43210.
D000818:Animals; D001706:Biopsy / Q000662:veterinary; D001715:Bird Diseases / Q000175:diagnosis* / Q000188:drug therapy; D005241:Feathers / Q000473:pathology; D007037:Hypothyroidism / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D008297:Male; D010311:Parrots; D012867:Skin / Q000473:pathology; D013960:Thyroid Function Tests / Q000662:veterinary; D013974:Thyroxine / Q000627:therapeutic use
D013974:Thyroxine