Osteodistrofia fibrosa nutricional em jacarés de cativeiro no Estado da Paraíba

Abstract

Crocodilians are subdivided in three families: Alligatoridae, Crocodylidae and Gavialidae in a total of 23 species. When young they feed small fish and crustaceans, in adulthood consume vertebrates including fish, turtles, birds and mammals. Metabolic bone disease involves a group of pathological conditions developed as result of prolonged deficiencies in calcium, phosphorus and vitamin D. Fibrous osteodystrophy is a metabolic bone disease most commonly found in captive reptiles. The pathogenesis occurs by stimulation of the parathyroid glands due to decrease in plasma concentrations of calcium, stimulating the secretion of parathyroid hormone as a compensatory mechanism. Reports of problems on nutritional management are constant, however few information is available for these species. In this study, the diagnosis of fibrous osteodystrophy in 17 caimans from three different species was based on epidemiological aspects, clinical history, radiographic alterations, and mainly macroscopic and histopathological findings. Radiographs revealed osteopenia, bone thinning, tortuosity of the vertebrae and fractures areas. In the necropsy were observed variables degrees of bone fragility, spinal deformities, bilateral symmetrical enlargement of the long bones and parathyroid markedly increased. The histopathological findings consisted of marked rarefaction of bone matrix with severe thinning from maxillary and frontal bone forming numerous cystic areas with islands of cartilage calcified and intense replacement by fibrous tissue. The absence of injury at the renal parenchyma and parathyroid tumors in all animals confirm the diagnosis of fibrous osteodystrophy by nutritional secondary hyperparathyroidism. After feeding correction with 0.1 ml of calcium gluconate for each animal orally, no additional cases of disease was observed.