1Department of Animal Science, University of Tabriz, Tabriz, Iran
2Department of Animal Science, University of Tehran, Tehran, Iran
3Department of Animal Science, University of Minnesota, St. Paul, 55108, USA
4National Animal Breeding Center and Promotion of Animal Product, Karaj, Iran
5Departmentof Animal Science, Valfajr Agricultural Research Center, Tehran, Iran
Receive Date: 07 March 2014,
Revise Date: 07 March 2014,
Accept Date: 15 May 2014
The objective of this study was to evaluate the effects of weaning age on dry matter intake (DMI), average daily gain (ADG), feed efficiency (FE), feed cost (FC) and benefit index (BI) of Holstein calves reared under organic farming system. Thirty two Holstein calves were divided into two treatments: early weaning (EW) vs. late weaning (LW). Calves in the both groups were provided with whole milk at the rate of 10% body weight (BW). Calves had free access to leafy alfalfa hay from birth until the end of the experiment. Also, the EW group was provided with starter diet after weaning till 90 days of age.The daily DMI and BW at 15-day intervals were measured and FE and FC were calculated for periods. The DMI of LW and EW calves was significantly different from third period to end of experiment. Moreover, ADG of EW was higher than LW in all of periods.Except for first and second, FE was significantly different between the groups in other periods. Also, due to an increase FC for calves reared on LW compared to EW-calves group, the BI was higher in EW-calves.
AOAC. (1991). Official Methods of Analysis, 15th Ed. AOAC, Washington, DC, USA. Gleeson D.E., Brien B.O. and Fallon R.J. (2007). Feeding of cold whole milk once daily to calves in a group and its effect on calf performance, health and labour input. Int. J. Appl. Res. Vet. Med.5, 97-104. Hill T.M., Aldrich J.M., Schlotterbeck R.L. and Bateman H.G. (2006). Effects of feeding calves different rates and protein concentrations of twenty percent fat milk replacers on growth during the neonatal period. Prof. Anim. Sci.22, 252-260. Hill T.M., Bateman H.G., Aldrich J.M. and Schlotterbeck R.L. (2009). Effect of weaning age of dairy calves fed a conventional or more optimum milk replacer program. Prof. Anim. Sci.25, 619-624. Hudson M.D., Banta J.P., Buchanan D.S. and Lalman D.L. (2010). Cows and their progeny in a fall calving system in the southern great plains effect of weaning date (normal vs. late) on performance of young and mature beef. J. Anim. Sci. 88,1577-1587. Jasmine Rani K., Ganga Devi P., Mercy A.D., Shyama K. and Sujatha K.S. (2007). Effect of restricted milk feeding on growth performance in cross bred calves. Indian J. Anim. Nutr.92, 130-132. Kehoe S.I., Dechow C.D. and Heinrichs A.J. (2007). Effects of weaning age and milk feeding frequency on dairy calf growth, health and rumen parameters. Livest. Sci. 110, 267-272. Khan M.A., Lee H.J., Lee W.S., Kim H.S., Kim S.B., Ki K.S., Ha J.K., Lee H.G. and Choi Y.J. (2007). Pre- and post-weaning performance of Holstein female calves fed milk through step-down and conventional methods. J. Dairy Sci. 90,876-885. Littell R.C., Henry P.R. and Ammerman C.B. (1998). Statistical analysis of repeated measures data using SAS procedures. J. Anim. Sci.76, 1216-1231. NRC. (2000). Nutrient Requirements of Beef Cattle, 7th Rev. Ed. National Academy Press, Washington, DC. USA. Ozkaya S. and Turan Toker M. (2012). Effect of amount of milk fed, weaning age and starter protein level on growth performance in Holstein calves. Arch. Tierz.55, 234-244. Purvis H.T. and Lusby K.S. (1996). The effects of early weaning on intake of native hay in fall calving cows. Res. Rep. Oklahoma Agric. Exp. Stn. Oklahoma Agric. Exp. St. 120-125. Quigley J.D., Caldwell L.A., Sinks G.D. and Heitmann R.N. (1991). Changes in blood glucose, nonesterified fatty acids, and ketones in response to weaning and feed intake in young calves. J. Dairy Sci. 74, 250-257. Rymer C., Vaarst M. and Padel S. (2006). Future perspectives for animal health on organic farms: main findings, conclusions and recommendations from SAFO network. Pp. 145 in Proc. 5th SAFO Workshop, Odense. SAS Institute. (2004). SAS/STAT Software, Release 9.1.3. SAS Inst. Inc., Cary, NC. Story C.E., Rasby R.J., Clark R.T. and Milton C.T. (2000). Age of calf at weaning of spring-calving beef cows and the effect on cow and calf performance and production economics. J. Anim. Sci.78, 1403-1413. Terre M., Devant M. and Bach A. (2007). Effect of level of milk replacer fed to Holstein calves on performance during the preweaning period and starter digestibility at weaning. Livest. Sci.110, 82-88. Vasseur E., Borderas F., Cue R.I., Lefebvre D., Pellerin D., Rushen J. and Wade K.M. (2010). A survey of dairy calf management practices in Canada that affects animal welfare. J. Dairy Sci.93, 1307-1315. Wagenaara J.P., Klockeb P., Butlerc G., Smoldersd G., Nielsene J.H., Caneverf A. and Leifert C. (2011). Effect of production system, alternative treatments and calf rearing system on udder health in organic dairy cows. NJAS-WageningenJ. Life Sci. 58, 157-162. Windsor P.A. and Whittington R.J. (2010). Evidence for age susceptibility of cattle to Johne’s disease. Vet. J.184, 37-44.