Liveweight gain and intake of Friesian bulls grazing ‘Grasslands Puna’ chicory (Cichorium intybusL.) or pasture

Abstract

A leader (4-month-old calf)-follower (15-month-old bull) system was used to graze mid-reproductive growth chicory and mature pasture at two herbage allowances. Chicory leaf allowances of 83 and 23 g dry matter (DM)/kg liverweight (LW) per day gave calf liveweight gains of 0.62 and 0.57 kg/day. For bulls, chicory leaf allowances of 8 and 4 g DM/kg LW per day gave liveweight gains of 0.45 and 0.09 kg/day. Pasture leaf allowances of 43 and 21 g DM/kg LW per day gave calf liveweight gains of 0.62 and 0.60 kg/day; and bull liveweight gains of 1.1 and 0.79 kg/day for pasture leaf allowances of 8 g DM/kg LW per day. Chicory consisted of 48% main stem and 27% live leaf before calf grazing; and 50% main stem and 19% leaf after calf grazing at the high allowance and 38% stem and 11% leaf at the low allowance. Calves and bulls preferentially grazed leaf before stem on both chicory and pasture. Live chicory leaf had 77% dry matter digestibility (DMD) and 1.5% nitrogen (N) compared with the main stem of 46% DMD and 0.24% N. Pasture DMD before grazing was 60% with 1.6% N. The provision of high chicory leaf allowances will enable high liveweight gains to be achieved from reproductive swards. However, good management should minimise stem because of its low DMD and N content and low acceptability to both calves and bulls.