Abstract:
Proc. Aust. Soc. Anim. Prod. Vol. 17 RICE HUSK AS A SURVIVAL RATION FOR BEEF CATTLE _ _ _ J.F. KIDD , J.A. LINDSAY and M.D. CERVONI 427 Rice husk, a by-product of the Burdekin rice industry, is recognised as having a low nutritional value due to a low digestibility and high content of fibre and silica. The present study examined the role of rice husk as a roughage additive to drought affected cattle fed a molasses-based diet. Twenty-four Zebu crossbred steers were randomly allocated to one of six pens with two replicates of three rations. The rations were: ground rice husk (RH); RH plus rice Pollard in the ratio 2 to 1 (RHP) and RHP plus 10% cottonseed meal. These rations were offered at restricted intakes and a basal diet of ad libitum molasses plus 6% urea W/W (M6U) was offered for 92 days. Table 1. Mean liveweight gain and molasses intake * Means with dissimilar postscripts are significantly different (P(O.05). Mean intake of ground rice husk (RH) was 1.83 and 2.83 kg/d for days 1 to 28 and 28 to 92 respectively. The M6U intake (ad libitum) was about 1.45 kg/d for all treatments for days 1 to 28. During the final 64 days the intake of M6U was much higher and differences between rations (Table I) were significant (PCO.05) . Liveweight loss during the first 28 days is likely to be due to diet adaption and the low intake of ration. During the last 64 days there was a significant increase in liveweight gain as Pollard (RHP) and then cottonseed meal (RHP+CSM) was fed with the RH. These responses are partly explained by significant increases in feed intake. The feed conversion ratio improved (PCO.05) as Pollard and then cottonseed meal was added, perhaps indicating a better balance of nutrients and a better utilisation of the ration. From these results it appears that addition of energy and protein are necessary to promote adequate liveweight gains in cattle fed a basal diet of ground rice husk and molasses plus 6% urea. The liveweight gain recorded with rice husk, Pollard and cottonseed meal means that this ration may be useful as a production ration, e.g. to extend the growing season or with short-term feeding to overcome transport bruising prior to slaughter. _ Queensland Dept Primary Industries, Swan's Lagoon, Millaroo, Qld 4807