Geese and dietary allelochemicals — food palatability and geophagy |
| |
Authors: | Michael Wink Angelika Hofer Martin Bilfinger Elke Englert Martinus Martin Dietrich Schneider |
| |
Affiliation: | (1) Institut für Pharmazeutische Biologie der Universität Heidelberg, Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany;(2) Max-Planck-Institut für Verhaltensphysiologie, D-82319 Seewiesen, Germany |
| |
Abstract: | Summary The palatability of plants was studied in young, immature and adult geese of three species,Anser anser, Anser indicus andBranta canadensis, with respect to secondary plant metabolites. In their first 1–4 weeks of life, hand-reared goslings feed on a wide variety of plants, more or less irrespective of their allelochemical contents. Older birds become more selective, but still consume plants which are normally considered to be unpalatable or even toxic for other animals. Choice experiments were performed with pure secondary metabolites which were offered on otherwise highly palatable food items, such as leaves ofTaraxacum officinale. These experiments revealed a similar trend, in that very young goslings discriminate their food much less than older goslings or adult geese. In general, food contaminated with essential oils was rejected, whereas alkaloids, glycosides, amines and sulfur compounds were tolerated to a remarkable degree. In consequence, especially young, but also adult geese must have a high capacity to tolerate and/or to detoxify dietary allelochemicals. Another detoxification mechanism became evident during the experiments: geese ingest soil and mud quite regularly. It could be shown experimentally that the respective soil had a high capacity to bind alkaloids. We assume that geophagy is a means (besides a presumed active detoxification in the liver) to adsorb and thus reduce the contents of dietary allelochemicals. |
| |
Keywords: | allelochemicals chemical defence choice experiments food selection geophagy herbivory Anseriformes Anser anser Anser indicus Branta canadensis |
本文献已被 SpringerLink 等数据库收录! |
|