Comparison of tannin-binding proteins in saliva of Scandinavian and North American moose ( Alces alces)

Abstract

Differences in the ability of salivary proteins from Scandinavian and North American moose ( Alces alces) to bind tannins from various preferred food plant sources were studied. Both Scandinavian and North American moose produce a salivary tannin-binding protein which binds only condensed tannins common in their diet. The tannins of winter-browsed stems of Pinus sylvestris and Salix pentandra were more effectively bound by salivary tannin-binding protein from North American moose than by those from Scandinavian moose. Tannins of P. sylvestris and S. pentandra stems were also more effective binding agents than tannins from S. caprea and Betula species. The interactions between salivary tannin-binding protein and plant tannins may be one factor affecting food plant choice of moose. The chemical and biochemical characteristics of plant tannins and the ability of salivary tannin-binding proteins to react with tannins should be taken into account in diet selection.