Feed intake and behaviour of kids and lambs fed sugar cane as the sole roughage with or without concentrate

Two experiments were carried out to examine effects of physical form of whole sugar cane (WSC) and different proportions of WSC offered with or without a concentrate on feed intake, selection and behaviour of weaned kids and lambs. Both experiments were 14 days long with a 7 days adaptation period and the following 7 days for data collection. In Experiment 1, 16 weaned lambs and 16 kids were fed WSC as a sole feed at a level of 5% of the initial body weight, chopped in two different ways into (i) 1-3 cm slices or (ii) 20 cm lengths split into four parts. During the last 3 days of the experiment, four kids and four lambs were chosen from each experimental group for observations of behaviour. Both kids and lambs fed with WSC chopped in slices (1-3 cm) had higher daily dry matter intake (DMI) than those fed WSC chopped in 20 cm lengths and eating time was reduced as chop length of WSC decreased. Kids had higher DMI (30%) than lambs and spent more time eating and had more eating bouts. Both kids and lambs were able to select WSC with a higher nutritive value than the WSC offered. Both species had the same rumination time and eating mode but the frequencies for each eating mode were different. In Experiment 2, 32 lambs and 32 kids were offered WSC at 415, 6 or 7% of initial body weight as slices (1-3 cm) or 20 cm long pieces split into four parts. The WSC was fed with or without concentrate at a level of 1% of initial body weight. DMI of lambs was highest when WSC was offered at 6% of body weight, significantly higher than the 4 and 5% levels but not from the 7% level. DMI of WSC of kids was not significantly changed as the amount of WSC offered was increased. Adding a supplemental concentrate had no effect on the DMI of WSC, only on total DMI. Animals fed 1-3 cm pieces of WSC had higher intake than those fed with 20 cm pieces, consistent with Experiment 1. (C) 2002 Elsevier Science B.V. All rights reserved.