Summary of mineral and iron binding polyphenolic plant compound levels in diets offered captive black rhinoceros (Diceros bicornis) in 3 zoos and 1 ranch in Texas

Hemosiderosis is commonly noted in captive black rhinoceros but not free-ranging animals. Animals held in a ranch setting, offered a diet containing at least 46% browse on a dry matter basis, do not experience the same health problems as animals in zoos. It is known that plants contain polyphenolic compounds that can bind iron and make it unavailable for absorption....