VERTEBRAL HYPEROSTOSIS IN ANTEATERS (TAMANDUA-TETRADACTYLA AND TAMANDUA-MEXICANA) - PROBABLE HYPERVITAMINOSIS A AND OR D/

Hyperostosis of the thoracolumbar and coccygeal spine was seen in five captive tamanduas (Tamandua retradactyla and Tamandua mexicana). Radi ologic signs of the condition, evident within the first year of captiv ity, progressed from a small subvertebral linear density to massive ve rtebral hyperostosis and fusion. Clinical signs only developed in one tamandua with advanced hyperostosis. Soft tissue mineralization, obser ved during postmortem examination, is common in tamanduas in other toe s. Plasma calcium levels were not significantly higher in captive tama nduas than in nine wild animals sampled. Plasma phosphorus, vitamin A, and vitamin D levels were considered normal, but liver vitamin A leve ls were higher than levels in most normal domestic animals. Vitamin le vels in the diet were progressively reduced over 5 yr from a high of 5 7,000 IU/kg vitamin A and 6,700 IU/kg vitamin D (dry matter basis) to 22,000 IU/kg and 1,900 IU/kg, respectively. Hyperostosis developed mor e slowly in animals fed diets containing the lower levels of vitamins A and D, concentrations still considered excessive for this genus. The condition is most likely caused by chronic hypervitaminoses A and/or D.