THE EFFECTS OF GRAZING CHICORY (CICHORIUM-INTYBUS) AND BIRDSFOOT-TREFOIL (LOTUS-CORNICULATUS) ON VENISON AND VELVET PRODUCTION BY YOUNG REDAND HYBRID DEER

The effects of grazing chicory, Lotus corniculatus, and perennial ryeg rass/white clover pasture on growth, voluntary feed intake (VFI), and venison and velvet production was studied in red and hybrid deer from weaning to slaughter at one year of age. Twenty five percent of red an d 75% of hybrid stags attained the target slaughter weight (50 kg carc ass or greater) when grazing pasture and spiker velvet antler weight w as low (approximately 0.2 kg/stag). Mean carcass weight of deer grazin g chicory was higher than for deer grazing pasture (P < 0.05), due to increased liveweight gain (LWG) in both autumn and spring, and to high er dressing-out percentage at slaughter. Carcass weights for red and h ybrid stags were 56.0 and 59.3 kg, respectively, when grazed on chicor y and 48.6 and 53.3 kg, respectively, when grazed on pasture (P < 0.01 ). Hybrid hinds grazing chicory had a significantly higher carcass wei ght (P < 0.05) and dressing-out percentage (P < 0.01) than those grazi ng pasture. Chicory had a higher organic matter digestibility (OMD) th an pasture, and VFI was higher than on pasture during autumn but was s imilar in spring. Relative to pasture, chicory grazing increased total spiker velvet antler production (323 v 225 g/stag) by advancing the d ates of pedicle initiation, antler initiation, and of first velvet cut ting and increasing the rate of velvet antler length growth. Initiatio n of velvet growth was correlated with liveweight (LW), with each 10 k g increase in LW advancing the dates of pedicle initiation, commenceme nt of velvet growth, and first velvet cutting by 10, 18, and 13 days, respectively. Earlier velvet growth in deer fed chicory could thus lar gely be explained by the higher liveweight of deer grazing this forage . Observations from deer grazing lotus were limited due to problems wi th lotus establishment. Grazing lotus increased LWG of stags during au tumn compared with perennial ryegrass/white clover pasture (248 v 176 g/day) and increased the efficiency of growth in spring, with LWG bein g similar to deer grazing pasture, but VFI being lower (1.53 v 2.00 kg OM/day). OMD of lotus was higher than pasture during autumn, but not in spring. Stags grazing lotus produced similar velvet antler weight t o stags grazing pasture. Total condensed tannin (CT) concentration in hand plucked and oesophageal fistulae (OF) extrusa samples, respective ly, were 48 v 13 g/kg OM for lotus, 3.1 v 5.8 g/kg OM for chicory, and 0.3 v 1.5 g/kg OM for pasture. It was concluded that chicory was of h igh feeding value for increasing venison and velvet production from yo ung deer. Results suggest that the CT content of lotus may improve the efficiency of growth in young deer.