Abstract:
Proc. Aust. Soc. Anim. Prod. Vol. 18 FEED INTAKE, LIVEWEIGHT GAIN AND WOOL GROWTH OF MERINO WETHERS FED GRASS OR LEGUME HAYS G.R. SAUL* and H.A. CHANNON** Legume forages have a higher feeding value then grasses (Ulyatt 1981) but there are few data available on the relative value of Persian clover (T. resupinatum) and Balansa clover (T. balansae) compared to more common legumes. This study compared the feeding value (liveweight gain, LWG; wool growth, WG) and digestible organic matter (DOM) intake of sheep fed Balansa or Persian clover hays, grass hay or lucerne cubes of similar in-vitro DOM. Forty eight fine wool Merino wethers, 2.5-3.5 years old, 30-45 kg live <weight were individually penned under cover and randomly allocated to a forage type and feeding treatment. Feeding was either ad libitum (Ad) or maintenance (M) The 28 d experimental period followed a similar adaptation (MAFF 1984). period. In-vivo DOM was determined on M sheep'over 4 d immediately prior to the experimental period. Grass hay contained mainly L. perenne with some Bromas mollis, Holcue lanatus and Anothoxanthum odoratum, but only 5% clover. Persian and Balansa hays contained 85% and 75% respectively sown species, the balance being grass weeds. Lucerne cubes were used to avoid selection by the sheep which had been previously encountered with long lucerne hay. Results are given in Table 1. Table 1 Effect of forage type on feeding value Wethers consuming Balansa or Persian clover ad libitum grew 34% and 39% more wool and gained 40% and 77% more live weight respectively, than sheep fed grass hay of similar DOM. Persian clover retains its high feeding value later into the season than Balansa (Saul, unpublished) and regrows strongly after mowing making it the preferred species in high rainfall areas. Given the similar invitro DOM% of the hays, NDF was the most consistent indirect index of feeding value. Lucerne cubes prevented selection of leaf over stem and gave high animal performance, but the result may have been partially affected by the cubing process and may not truly represent long hay. MAFF (1984). 'Energy Allowances and Feeding Systems London). ULYATT, X.J. (1981). NZ J. Agric. Sci. lS(4): 200. for Ruminants'. (BMSO: Dept Agriculture and Rural Affairs, Pastoral Research Institute, Hamilton, Vic. 3300. ** Rutherglen Research Institute, Rutherglen, Vic. 3685. * 545
