Abundance of intestinal Na+/glucose cotransporter (SGLT1) in roe deer (Capreolus capreolus)

The abundance of SGLT1 in domestic grazing ruminants is regulated by the sugar concentration of the digesta reaching the small intestine and decreases with the development of the rumen. Roe deer select easily digestible forage to satisfy their relatively high energy requirements and are expected to avoid energy losses by microbial fermentation in the rumen. To investigate the role of a numen bypass, respectively, ruminal escape, we measured the abundance of SGLT1 protein by Western blotting and the maltase activity in the small intestine as indicators for the presence of sugars. The abundance of SGLT1 protein in adult roe deer did not differ from that of lambs and rabbits and was much higher than in adult sheep. Maltase activity of roe deer and moose tended to higher values than that of sheep and gear. This pointed to the presence of glucose in the digesta of concentrate selectors and reflected the obvious differences in nutrient utilization of ruminants of different feeding type.