Variation in ruminal nitrogen levels among some cervidae.

Abstract

Among black-tailed deer (Odocoileus hemionus sitkensis), roe deer (Capreolus capreolus), and reindeer (Rangifer tarandus), nitrogen levels in the contents of the rumen show consistent patterns of variation. Among deer of each species on the same range during the same season, the animal-derived nitrogen component of the rumen contents decreases as the vegetative nitrogen component increases. This inverse relationship may result from one, or more likely both, of the following causes. (1) The ability of the ruminant to maintain a fairly constant rumen environment to allow for its most efficient function. (2) An adaptability in these deer species to compensate for low nitrogen levels in the forage by recycling of nitrogen through the saliva and further conservation of ruminal nitrogen by recycling it through successive generations of microbial populations. The apparent ability to compensate for variations in forage nitrogen levels is limited when deer are on range of general poor quality or during fall and winter when forage nitrogen levels are reduced.