Dietary iron absoption ant the role of tannins in Eastern (Diceros bicornis michaeli) and Southern black rhinoceros (Diceros bicornis minor)

Three diet treatments were fed for at least 6 months at 6 institutions to a total of 11 black rhinoceros to assess the effect of tannins on iron status. Diet treatments were: 1.) a pellet/mixed hay diet, which reflected the diet historically fed; 2.) a pellet/mixed hay diet with quebracho added to the pellets as a source of iron binding...

The effect of length of cold storage on secondary plant compounds in browse for captive black rhinoceros (Diceros bicornis)

The endangered black rhinoceros (Diceros bicornis) suffers from a high rate of mortality in captivity due to conditions such as hemosiderosis and hemolytic anemia. Supplementation of the diet with native browse species rich in tannins and other iron-binding polyphenolics has been proposed as a dietary strategy for reducing iron absorption and accumulation in this population. This study examined the effect...

The effect of sample handling and preparation on the iron binding polyphenolic content of browse

The objective of this study was to determine feasible handling methods for accurate analysis of iron binding polyphenolics. Seven methods were tested with different combinations of both onsite handling and laboratory preparation. In these methods, on-site collection included freezing the samples with liquid nitrogen or dry ice or collecting the samples fresh and returning them to the lab. Once in...

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....