title: Hypophosphatemic rickets in rheas (Rhea americana).
abstract: Rickets was diagnosed in 11 rheas from four flocks in Ohio. At necropsy, had pliable bones with prominent valgus or varus deformation of the femoral bone and/or the tibiotarsal bone, marked thickening of the metaphyseal plates, and frequent fractures. Histopathologically, bones of rachitic birds showed marked retention of cartilage core within the growth plate, mainly because of a significant lengthening of the hypertrophied zone of the growth plate in relationship to the remaining zones. Feed analysis showed that rachitic birds were fed diets having higher calcium/phosphorus (Ca/P) ratios (1.38-4.32) than that of the diet fed to nonrachitic birds from a different flock (0.65 Ca/P ratio). Serum analysis of blood from clinically rachitic birds from the affected flocks revealed a marked hypophosphatemia (3.0-4.7 mg/dl), mild hypocalcemia, and normal 25-(OH)-vitamin D concentrations as compared with values in nonrachitic birds, which had serum phosphorus concentrations of 8.5-8.7 mg/dl. These findings suggest that rickets in growing rheas was associated with marked hypophosphatemia and improper Ca/P ratios.
authors.affiliation: Department of Veterinary Pathobiology, Ohio State University, Columbus 43210, USA.
authors.forename: A
authors.initials: A
authors.lastname: Gröne
authors.forename: D E
authors.initials: DE
authors.lastname: Swayne
authors.forename: L A
authors.initials: LA
authors.lastname: Nagode
mesh_terms: D000818:Animals; D001715:Bird Diseases / Q000097:blood / Q000209:etiology / Q000473:pathology*; D001717:Birds; D001846:Bone Development; D001842:Bone and Bones / Q000473:pathology; D002118:Calcium / Q000097:blood; D002136:Calcium, Dietary / Q000009:adverse effects*; D006132:Growth Plate / Q000502:physiology; D006887:Hydroxycholecalciferols / Q000097:blood; D017674:Hypophosphatemia / Q000473:pathology / Q000662:veterinary*; D010710:Phosphates / Q000097:blood; D016226:Phosphorus, Dietary / Q000009:adverse effects*; D012279:Rickets / Q000097:blood / Q000473:pathology / Q000662:veterinary*
chemical_list: D002136:Calcium, Dietary; D006887:Hydroxycholecalciferols; D010710:Phosphates; D016226:Phosphorus, Dietary; D002118:Calcium