Abstract:
5A A simple lot feeding system for lambs J.J. Davis1 and M. Quilford 2 1 2 Agriculture Victoria, Rutherglen Vic 3685 University of Melbour ne, Dookie Vic 3647 jenny.davis@nre.vic.gov.au A simple lot feeding system for finishing prime lambs was investigated. Second_cross lambs (n=600) aged 5 months, from Border Leicester x Merino ewes and sired by either Poll Dorset or White Suffolk rams, with an average live weight of 35.5 � 5 kg were used. The lambs were shorn, dosed with anthelminthic, and trail fed a 70:30 mixture of oats/lupins for 2 weeks prior to allocation to treatments. They were fed in plots (0.5 ha) which had wheat stubble that was heavily grazed before the lambs entered. They were randomised on sex, live weight, and sire for allocation to dietary treatment (Table 1); each treatment was replicated three times (50 lambs per plot). Bentonite (2%) and bicarbonate (1%) were added to each diet, and lucerne hay (23 kg) was placed in each plot every second day during the trial. The grain ration was available ad libitum from a stock feeder. After a 6 week feeding period lambs were slaughtered at a commercial abattoir. Measurements were made of live weight (LW), hot standard carcase weight (HSCW), and GR tissue depth; average daily gain (ADG) and average feed conversion ratio (FCR) were calculated. There were no significant differences between experimental diets in terms of live weight gain, carcase weight or GR (Table 2). The urea diet was the most cost effective for live weight gain and was significantly cheaper than the sunflower diet. Table 1 Composition and cost of experimental rations. Experimental diets Triticale, % Oats, % Lupin, % Urea, % Canola, % Sunflower meal, % ME, MJ/kg DM Cr ude protein, % Cost, $/tonne 10.96 15.21 168.85 10.77 15.34 159.05 10.53 15.63 191.78 Control 25.5 46.5 25 Urea 34 51 11 1 23.5 22.5 10.92 15.31 186.71 Canola 25.0 48.5 Sunflower 34.5 41 Table 2 Live weight, average daily gain, feed conversion ratio, hot standard carcase weight and GR tissue depth of lambs fed grain for 6 weeks. Experimental diets Initial LW, kg Final LW, kg ADG, g/d Intake, kg/d FCR, g/g HSCW, kg GR, mm Cost($)/kg LW gain Control 35.3 46.5 271 1.95 7.32 20.2 10.7 1.22 Urea 35.6 46.5 269 1.87 6.72 20.0 9.9 1.07 Canola 35.3 45.3 241 1.95 8.04 19.9 9.9 1.17 Sunflower 36.0 46.8 260 1.81 6.65 20.3 10.0 1.46 SEM 0.49 0.89 18 0.24 0.81 0.35 0.41 0.14 Recent Advances in Animal Nutrition in Australia, Volume 13 (2001)