Abstract # 49:

Scheduled for Saturday, September 19, 2009 06:30 PM-09:00 PM: Session 5 (Mission Bay Ballroom CDE) Poster Presentation


M. Mau1, K. H. Südekum1, A. Johann2, A. Sliwa3 and T. M. Kaiser4
1University of Bonn, Institute of Animal Science, Endenicher Allee 15, Bonn 53115, Germany, 2Naturzoo Rheine, Salinenstr. 150, Rheine, 48432, Germany, 3Kölner Zoo AG, Riehler Str. 173, Köln, 50735, Germany, 4University of Hamburg, Zoological Institute and Museum, Martin-Luther-King-Platz 3, Hamburg, 20146, Germany

Gelada baboons have developed special adaptations to grass diet such as high-crowned teeth for processing hard and abrasive feed. The fine-tuning of salivary protein composition might be another key mechanism that is used by species to adapt to the environment and to compete with rivals for exploiting new ecological niches. In this study we compared whole saliva from twelve captive Theropithecus gelada (graminivorous) and six Papio hamadryas (omnivorous). We hypothesized that the amount of proline-rich salivary proteins (PRP) with tannin-binding capacity is higher in baboons consuming a feed with high dicot/monocot rations. Dicots produce tannins as a chemical defense system, discouraging animals from eating them. In contrast to dicots, monocots do not synthesize tannins. The presence of tannin-binding proteins (TBP) in saliva should effectively inactivate the dicot tannins and increase the dietary breadth. The lack of TBP would indicate a narrow dietary spectrum more restricted to monocots. We further hypothesized a secreted salivary alpha-amylase to point to the use of dietary starch in primates. Unlike hamadryas baboons, geladas completely lacked PRP and TBP. Nonetheless, salivary alpha-amylase was also present in geladas. This might help to explain observations in free-ranging geladas, which seasonally supplement their diet with grass seeds and storage roots. Our results support a growing body of evidence suggesting an obligate graminivorous specialization of T. gelada exploiting both grass blades and seeds. Support: DFG SU 124/15-1.