Dietary β-Carotene Absorption and Metabolism in Ferrets and Rats

Abstract

The ability of the ferret (Mustela putorius furo) to absorb dietary β-carotene was studied to determine its appropriateness as a laboratory animal model for studies on β-carotene metabolism. At baseline, the mean serum β-carotene level in ferrets was 0.6 µg/dl and no β-carotene was present in liver or adipose tissue. After the ferrets were fed 4 or 20 mg of β-carotene/kg body wt daily for 2 wk, serum levels were 15.3 and 41.5 µg/dl, liver values were 0.9 and 4.1 µg/g and adipose tissue values were 0.1 and 0.2 µg/g of β-carotene, respectively. Thus, like humans, ferrets are able to absorb dietary β-carotene intact. Further, these animals can store quantifiable amounts of dietary β-carotene in their liver and, to a lesser extent, in adipose tissue. In contrast, serum β-carotene levels in rats fed the two levels of β-carotene were very low (0.5 to 0.6 µg/dl) and no β-carotene was found in liver or adipose tissue. Thus, the ferret is a more appropriate animal model for studying the intestinal absorption of β-carotene and its storage and metabolism in body tissues.