Abstract:
Proc. Aust. Soc. Anim. Prod. (1978) 12: 169 DROUGHT RATIONS OF GRAIN AND HAY FOR WEANED CALVES A.H. BISHOP* and I.E. SAXTON During the 1967-68 drought in western Victoria, demonstrations of survival feeding of young cattle at the Pastoral Research Institute indicated that major uncertainties were whether wheat needed to be crushed and whether hay should be fed with grain. In experiment 1, three groups of 17 calves aged 8 to 10 months and weighing 155 kg which had been on drought rations for 4 months were fed diets of 2.50 kg per day of whole kwheat, crushed wheat and whole oats, commencing on March 12, 1967. In experiment 2, four groups of 17 calves of similar age but weighing 190 kg which had been on grain rations for 6 weeks were fed the following diets 1) 3.14 kg whole wheat, 2) 1.54 kg whole wheat and 2.72 kg hay, 3) 2.20 kg whole wheat and 1.87 kg hay, 4) 2.17 kg crushed wheat and 1.87 kg hay. In both experiments feeding continued for 47 days. In experiment 1, uneaten crushed wheat removed from troughs amounted to 6% of that given whilst about 1% of the oats was left. Undigested grain`was observed in the faeces of the groups receiving whole wheat. The calves receiving crushed wheat showed mild distress and there were two deaths in this group, one attributed to ostertagia and the other to acidosis. In experiment 2 a small amount of crushed wheat was left uneaten on several occasions but no calves died or became distressed. TABLE 1: Liveweight change of calves during feeding (kg) The similar performance of steers on whole oats and whole wheat is of interest. Crushing wheat provided no advantage in experiment 1 when only grain was fed, whereas there was a weight advantage of 9 kg for crushed wheat over whole wheat in experiment `2 when hay provided 45% of the ration. The inclusion of hay with crushed wheat appeared to overcome the problem of acidosis and feed refusal. Toland (1976) found that when fed with hay, the digestibility of wheat was improved by crushing, but Pryor and Laws (1972) considered that wheat may not need processing. Crushed wheat plus hay was an effective diet but it may be impractical because of the labour and-cost of crushing, the scarcity of hay in a long drought, and the greater risk of deaths with crushed wheat. We conclude that whole oats, whole wheat plus hay, and whole wheat alone are suitable rations for calves and may all be appropriate at different stages of a prolonged drought. PRYOR, W.J. and LAWS, L. (1972). Aust. vet. J. 48:500. TOLAND, P.C. (1976). Aust. J. exp. Agric. Anim.Tusb. 16:71. * Pastoral Research Institute, P.O. Box 180, Hamilton, Vic. 3300. t Present address: Shady 'Creek Road, Darnum, Vic. 3822. 169. '