PROJECT SUMMARY:
This proposal addresses research priorities of high morbidity and mortality, skewed natal sex ratios, and inadequate knowledge of basic rhinoceros biology.

It is based on past and current studies in the applicant's laboratory and elsewhere indicating that rhinoceros blood cells are restricted in antioxidant capacity, and that widespread tissue deposition of iron pigments (hemosiderosis) in black and Sumatran rhinos, commonly (but often incorrectly) ascribed to hemolytic disease, actually represents a clinically significant iron overload syndrome (hemo-chromatosis), which, in addition to its inherent hazards, may contribute directly to various disorders affecting these species. Principal long-range objectives are:

(1) to assess the nature and severity of iron overload and reduced antioxidant capacity in captive rhinoceroses
(2) to collaborate in studies designed to determine their pathophysiologic mechanisms and consequences, and
(3) to collaborate in development of strategies for prevention and correction of their adverse effects. Specific aims to achieve these goals include:

(a) assessment of current trace-metal and antioxidant status of all available rhinoceros species in worldwide captivity compared to counterpart populations still under free-ranging conditions in native habitats
(b) evaluation of the role of increased body burdens of iron in causing or compounding certain clinical conditions and their modification by practical means. Research design to achieve these objectives will require