Matching between dietary preferences and digestive carbohydrase activities in Wisconsin birds

KOHL, K.; BRZEK, P.; CAVIEDES VIDAL, E.; KARASOV, W. H.

WISCONSIN, MADISON. USA

Congreso; Wisconsin Chapter of The Wildlife Society’s Winter Meeting; 2009

Wisconsin Chapter of The Wildlife Society´s Winter Meeting

It has been argued that evolutionary shifts in diet preferences are paired with changes in digestive physiology, including digestive enzyme activities. For example, a previous study in birds (Martinez del Rio 1990) found interspecific variation in enzyme activities that matched species´ feeding guilds (frugivore, omnivore, nectivore, etc). to enhance the findings of this study, we measured the activities of pancreatic and intestinal enzymes in six avian species where diet patterns have been extensively studied. The adaptative modulation hypothesis states that enzyme activities should match the relative levels of substrate present in an animal´s diet so as not to waste biosynthetic energy or cell membrane space with unneeded enzymes. There were no differences in aminopeptidase-N, trypsyn, or chymotrypsin activities between species with different percent protein in their diets. However, future studies may need to be conducted to differentiate long-term, evolutionary matching from rapid modulation of enzyme levels.