Digestibility and Related Nutritional Data for Seven Northern Deer Browse Species

Abstract

Energy use and related data are presented for seven northern winter foods of white-tailed deer (Odocoileus virginianus). Hemlock (Tsuga canadensis), balsam fir (Abies balsamea), red maple (Acer rubrum), striped maple (A. pensylvanicum), mountain maple (A. spicatum), hobblebush (Viburnum alnifolium), and hazelnut (Corylus cornuta) were fed in mixed rations to captive deer. Species tested had gross energy digestibilities ranging from 30 (red maple) to 54 percent (hobblebush). The amount of digestible, metabolizable, and net energy in each of the three maple species evaluated was very sim- ilar. Metabolizable energy ranged from 24 percent (1.2 kcal/g) for striped maple to 46 percent (2.2 kcal/g) for hobblebush. The lowest net energy was observed for striped maple (5 percent or 0.2 kcal/g), the highest for hobblebush (37 percent or 1.8 kcal/g). Crude protein was digested poorly in hemlock, balsam, and red maple (-5, 11, and 1 percent digestible, respectively) as compared with an average value of 47 percent for the remaining 4 species. The digestibilities of fat, fiber, and nitrogen-free extract of the seven plant species are presented and discussed. An example of the calculation of browse require- ment during a northern winter period, based on these and related data, is presented. J. WILDL. MANAGE. 40(4):630-638