U.S. Department of Agriculture: Animal and Plant Health Inspection Service
Date of this Version
1994
Abstract
Many plant defensive chemicals are bitter to humans. Because of this taste characteristic, and because bitter compounds are often toxic, such substances, and the plants that contain them, are regarded as generally unpalatable to wildlife. These assumptions may be unwarranted. To test the hypothesis that herbivores are indifferent to 'bitter' tastants, we investigated the responsiveness of guinea pigs (Cavia porcellus) to denatonium benzoate, denatonium saccharide, limonene, L-phenylalanine, naringin, quebracho, quinine, Ro-Pel (a commercial animal repellent containing denatonium saccharide) and sucrose octaacetate. Only quinine and sucrose octaacetate slightly but significantly reduced feeding (P < 0.05). Our findings are inconsistent with the notion that herbivores generally avoid what humans describe as bitter tastes.
Comments
Published in Journal of Chemical Ecology, Vol. 20, No. 2, 1994.