The performance of calves fed different concentrates while reared at pasture

Abstract

Proc. Aust. Soc. Anim. Prod. 1996 Vol. 21 THE PERFORMANCE OF CALVES FED DIFFERENT CONCENTRATES WHILE MILK REARED AT PASTURE J.B. MORANA and J.L. GRANTHAM B * Kyabram Dairy Centre, Institute of Sustainable Irrigated Agriculture, RMB 3010, Kyabram, Vic. 3620 * Bunge Feeds Pty. Ltd., Albury Road, Corowa, N.S.W. 2646 The feeding of formulated concentrate mixes to dairy replacement calves prior to weaning is now an accepted practice on northern Victorian dairy farms (Moran 1995). It is important that such concentrates be made as palatable as possible to stimulate their intakes during milk rearing and allow for early weaning of calves off milk by about 6 weeks of age. The following study was undertaken to assess the performance of calves, pre and post weaning, while fed one of 5 concentrates at pasture. Five herds of Friesian calves, each of 5 heifers and 5 bulls, were individually fed 4 L milk from buckets once daily between 2 and 7 weeks of age, together with ad Zibitum concentrates. Calves were allocated to herds on the basis of date of birth, sex and liveweight. Each herd was run in a separate paddock, containing 0.09 ha of irrigated white clover-based pasture, periodically offered limited hay, and shifted to a different paddock every 7 days in a 5 paddock rotation. Ad lib&urn water and shelter were provided in each paddock. The concentrates were rolled barley (BAR), standard Bunge calf pellets (STA), Bunge pellets plus 8% molasses (MOL), textured calf starter (TEX) and 'high bypass protein' pellets (BYP containing additional processed protein meals). The BAR contained 9.4% crude protein (CP) and 12.3 MJ/kg DM of metabolisable energy (ME), and the 4 formulated concentrates contained 22 to 24% CP and 11.5 to 12.5 MJ ME/kg DM. Concentrate intakes and liveweights were monitored every 7 days between Weeks 3 and 13 of the study, conducted during spring and summer 1994. Table 1. Pre and post-weaning concentrate intakes (kg DM/day), gr?wth rates (kg/day), and liveweights (kg) at weaning and 12 weeks of age in calves at pasture fed barley (BAR) or one of 4 formulated concentrates STA, MOL, TEX, BYP. MORAN, J.B. (1995). Proc. Amt. Ass. Cattle Vet. Con&, pp. 123-34. 342