Mineral absorption and secretion patterns in the alimentary tract of the roe deer (Capreolus capreolus)

Concentrations of macrominerals; Na, K, Ca, Mg, P, and Cl were measured in different sections of the alimentary tract of five roe deer, Capreolus capreolus, kept in captivity and fed a diet of grass pellets and oats. By means of the non-absorbed marker-slaughter technique (using 51CrEDTA as marker), sites of secretion and absorption of minerals in the alimentary tract were determined. Large amounts of P, Na and K were secreted into the rumen, whereas Cl was secreted into the abomasum. The larger amounts of these minerals were absorbed from the distal small intestine and caecum/proximal colon. In the coiled colon, small quantities of Na, K and Cl were absorbed which is essential for the maintenance of mineral balance. Emphasis is put on the role of the large hindgut in concentrate selectors both with respect to fermentation and conservation of minerals and other nutrients.