Feed intake, diet utilization, and composition of browses consumed by the Sumatran rhino (Dicerorhinus sumatrensis) in a North American zoo
Publication Type: |
Journal Article |
Year of Publication: |
2000 |
Authors: |
Ellen S. Dierenfeld, Robert E. C. Wildman, Steve Romo |
Publication/Journal: |
Zoo Biology |
Publisher: |
Inc., John Wiley & Sons |
Keywords: |
browse, herbivore nutrition, rhinoceros |
ISBN: |
1098-2361 |
Abstract:
Abstract 10.1002/1098-2361(2000)19:3<169::AID-ZOO1>3.3.CO;2-4 The Sumatran rhino (Dicerorhinus sumatrensis), presently indigenous to the Malay peninsula and the islands of Sumatra and Borneo, is faced with extinction. It is estimated that fewer than 400 individuals still exist in the wild. In response, concerted efforts have been made to maintain and breed this species in captivity, and proper diet and nutrition underlie reproduction. The present feeding trial characterizes a diet fed to three Sumatran rhinos at the Cincinnati Zoo and Botanical Garden. The diet consists of mixed alfalfa/orchard grass hay, a variety of browses, grain pellets, produce (apples and bananas), and a vitamin E supplement. All three rhinos maintained body weight (614–761 kg), regular patterns of bowel movements, and fecal consistency and composition throughout the three 5-day trials. Dry matter intake (DMI) ranged from 1.40 to 2.49% of body mass. Browse contributed by far the majority of nutrients to the diets in this study, from 62 to 83% of DMI. The nutrient composition of six species of subtropically grown browses (two from differing locations, for a total of eight browses characterized) showed that leaves did not differ from twigs in water or lignin content, but leaves contained higher concentrations of protein (both crude and bound) and ash, as well as lower fiber fractions. Of the macrominerals analyzed, only phosphorus differed between leaves and twigs, with twigs containing significantly more. No differences were seen between leaves and twigs in iron, molybdenum, or zinc content, but leaves contained lower concentrations of copper and higher concentrations of manganese and selenium compared with twigs from the same plants. Dry matter digestibility averaged approximately 50%. The only overt imbalances detected when comparing rhino diets with nutrient recommendations for domestic equids were excess calcium relative to phosphorus intake and low copper intake. These data, combined with information on native browse composition, intake, and digestibility, should greatly assist in providing suitable diets for this highly endangered species. Zoo Biol 19:169–180, 2000. © 2000 Wiley-Liss, Inc.