Effectiveness of the dairy cattle feed formulation system in developing lactating rations
Jones, G.M.; Wildman, E.E.; Wagner, P.; Lanning, N.; Chandler, P.T.; Bowman, R.L.; Troutt, H.F.
Journal of Dairy Science 61(11): 1645-1651
ISSN/ISBN: 0022-0302 DOI: 10.3168/jds.s0022-0302(78)83779-5
29 Virginia dairy herds were involved in a 12-month evaluation of the Dairy Cattle Feed Formulation System described by P. T. Chandler et al. [Proc. Nat. Ext. Workshop: Computerized Dairy Feeding-Management System, Dec. 8 (1977), Blacksburg, Virginia]. This system provides for least-cost feeding programmes while also considering various protein fractions, crude and effective crude fibre, net energy and declining digestibility of energy with increasing feeding rates, and 7 minerals. 13 herds used the system regularly, 5 were occasional users or made modifications to the recommendations and 11 herds followed other feeding recommendations. Increase in milk yield during the 12 months averaged 354, 220 and -39 kg/cow for the 3 groups of herds resp. Milk fat content, body wt. and body condition were not affected by frequency of using the formulation system. This study confirmed that least-cost rations can be fed to high-yielding dairy cows with excellent results. Interpretation of the feeding guidelines has been provided by G. M. Jones [Publication, Virginia Polytechnic Institute and State University, No. 755]. The 18 herds under study that were using the system either regularly or occasionally, were classified according to feeding system. Milk yield was higher when concentrate was provided in the parlour, either totally or as a supplement to the complete ration, or in an automatic feeder.