Secretion and absorption of nutrients in the alimentary tract of reindeer fed lichens or concentrates during the winter

Abstract

Water, organic matter (OM), N, Ca, P, K, Na, and Cl exchange was estimated in the alimentary tract of reindeer given concentrate or lichen diets alone or supplemented with minerals. Chromic oxide was used as a nondigestible marker and results are discussed in relation to inaccuracies of this marker technique. The pattern of water, OM, and N exchange was similar to other ruminants; over 61% of OM digestion was due to the rumen–reticulum plus omasum and abomasum (stomachs). For the concentrate diet, 40–60% of N digestion occurred in the stomachs. Apparent absorption of Ca, P, and Mg in the stomachs was linearly related to intake. Ca and Mg supplemented to lichens was excreted because of an inability of the intestines to recover mineral secreted into duodenal contents. In contrast, the jejunum absorbed P added to the diet. Excretion of K in feces at 0.076 mM/g fecal dry matter placed a limit on K absorption; it was negative on the lichen diet. Cl was absorbed in the small and large intestines. Supplemental Na, part of the P, Ca, and K, but none of the supplemental Mg added to the lichen diet was absorbed. Lichens appeared to bind some minerals and could thereby place a limit on their absorption.

Ceruloplasmin as an Indicator of Copper Reserves in Wild Ruminants at High Latitudes

“…2). This distribution is similar to those of macro-minerals (Ca, Mg, K and Na) in captive reindeer and in wild muskox Thing, 1991, Staaland et al, 1986) with net absorption of macrominerals centered on the small intestine (White et al, 1984). The concentration of trace minerals in digesta from reindeer suggests similar uptake from the small intestine even though most digestion of dry matter is achieved in the rumen (Fig.…”

“…2). Biliary secretions contribute to mineral concentration in digesta along the small intestine (White et al, 1984;Linder et al, 1998). Although these secretions can be absorbed at the ileum and along the hindgut, excess absorbed Cu and Zn are eliminated through bile.…”

“…The short growing season for plants at high latitudes provides a concomitantly brief season for production in moose, muskox (Ovibos moschatus), reindeer and caribou (Rangifer tarandus; White et al, 1987;Schwartz and Renecker, 1997). Summer production includes deposition of both lean and fat tissues in growing calves and in adult males before rut.…”

Forage diversity and nutrition supply of reindeer

“…Hypotetical forage-fecal balance of nitrogen and minerals for a reindeer feeding on a pure diet of Cladonia stellaris from Elgå herding district. Fecal concentrations are from a feeding experiment with reindeer fed a pure lichen diet (White and Staaland 1984 It is well established that reindeer can be in a negative-nitrogen and sodium balance through the winter (McEwan and Whitehead, 1970;Staaland et aL, 1982) and need to replenish their body pools in summer. Early green vegetation and plants including mushrooms, mountain sorell (Oxyria digyna) and other herbs are important nitrogen sources.…”

Trace elements in the alimentary tract of Svalbard reindeer

“…To calculate absorption or secretion of trace elements into the alimentary tract the methods described by White et al 1984 were used. This techique is based on a simple model which assumes that a constant amount of marker (AIA) flow through each section per unit time.…”