DIGESTION AND CHEWING BEHAVIOR OF YOUNG SAMBAR AND RED DEER CONSUMINGA LOW-QUALITY ROUGHAGE

Low quality chaffed meadow hay, containing 10.5 g N/kg dry matter (DM) , was fed to four artificially reared sambar (tropical) deer (Cervus u nicolor) and four red (temperate) deer (Cervus elaphus) confined indoo rs in metabolism crates at Palmerston North, New Zealand, during March and April 1994. Measurements were made of DM intake (DMI), apparent d igestibility, nitrogen (N) retention and the time spent eating and rum inating. Voluntary food intake (VFI), measured over days 7-11, was sub stantially greater for red deer than for sambar deer (67 v. 36 gDM/kgW (0.75)/day). Dry matter intake of red deer was then restricted, so tha t apparent digestibility could be better compared between the two spec ies. Eating and ruminating time/gDMI and chews during eating/gDMI were all greater for sambar deer than for red deer. Apparent digestibility of DM, organic matter (OM) and energy were low (c. 0.42) and not diff erent between deer species. Apparent digestibility of neutral detergen t fibre (NDF) and cellulose were highest for red deer, but lignin appa rent digestibility was highest for sambar deer. Both deer species lost weight and were in negative N balance. However, despite their lower N intake, sambar deer lost significantly less N and liveweight per day (-5.6 g and -118 g) than red deer (-12.2 g and -258 g). It was conclud ed that red deer responded to a diet of low quality roughage by increa sing VFI and cellulose digestion, whilst sambar deer responded with a lower VFI but greater chewing activity, improved lignin digestion and better N conservation. Rumen mean retention time should be measured in future experiments with sambar deer and red deer fed on low quality f orage diets.