PROJECT SUMMARY:
This project relates directly to the research priorities of the
Rhino TAG since nutrition is a factor identified as a likely contributor
to poor health and high mortality in black rhinoceros.
Rhinoceros
accumulate body stores of iron over their lifetime that may be
associated with numerous maladies. Eastern black rhinoceros have
a history of disease and death characterized by hemolytic anemia
and mucocutaneous ulceration (superficial necrolytic dermatopathy).
One eastern and 6 southern black rhinoceros in the south central
US recently sufferedfrom idiopathic hemorrhagic vasculopathy.
Many nutrients listed as possible causes in the rhinoceros syndromes
may be linked in some way to each other and to infection, immunity,
and cellular fragility or permeability.
Causes that may involve iron include: ferric iron antagonist vitamin
E, interactions between absorption of dietary iron and vitamin
E, and linkages between copper and iron absorption/functioning.
Iron
and copper are added to pelleted diets fed to rhinoceros. In the
absence of species specific data, levels are based on work performed
with domestic livestock. Natural browse of black rhinoceros contains
secondary plant compounds including tannins that may decrease
mineral absorption. Commercial hays contain tannins, but at lower
levels.
It is possible that these chemicals may bind excess dietary iron
in the natural diet. This study complements recent work and uses
it as a basis to follow-through with a more in-depth study of
dietary iron.
This
project's broad goal is to guide the development of a diet to
reduce the risk of iron overload in black rhinoceros. We will
evaluate nutritional status, iron/copper status in rhinoceros,
iron/copper balance and the role of dietary tannins in iron/copper
absorption.
The specific aims are to determine if
1) low, controlled dietary iron levels and then
2) low, controlled dietary iron plus dietary tannins affect iron/copper
status.
