HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Howard, W. T. Articles by Taylor, R. W. Search for Related Content PubMed Articles by Howard, W. T. Articles by Taylor, R. W.

Least-Cost Complete Rations for Dairy Cows ^{1, 2}

Department of Animal Sciences

R. W. Taylor

Department of Agricultural Economics, Purdue University, Lafayette, Indiana

ABSTRACT

Two least-cost linear programmed computer formulated rations were compared to a conventionally formulated ration in a 20-week continuous trial. Forty-eight cows averaging 57 days post-partum were randomly assigned to three treatments. Ration treatments were: 1) least-cost constant (LCC), formulated using the past year's prices; 2) least-cost variable (LCV), reformulated biweekly with price changes; and 3) a conventionally formulated control (no urea). Corn silage, the sole forage, and grain were thoroughly mixed and bunk fed ad libitum. Rations were designed to be nutritionally comparable. LCC and LCV rations were programmed for a maximum of 1% urea (air-dry basis). LCV ration ingredients were changed abruptly at biweekly reformulations.

Dry matter consumption per 100 kg body weight, actual milk, fat-corrected milk (FCM) production, milk fat and solids-not-fat (SNF) percentages, and body weight gains were not significantly affected by ration treatment. Abrupt ration changes did not under conditions of this research significantly (P < .05) affect animal performance. Daily feed costs were reduced significantly (P < .05) for the LCC and LCV rations, respectively, compared to the control. Analysis of opportunity costs indicated that the addition of urea accounted for about 60 % of the cost reduction attributable to the least-cost rations.

¹ Journal Paper no. 3156 of the Purdue Agricultural Experiment Station. Work conducted under Project 1407. This research was financed in part from a trust agreement between Purdue University and Normandy Farm, New Augusta, Indiana, Mr. and Mrs. Herman C. Krannert.

² Data taken from a dissertation by W. T. Howard in partial fulfillment of the requirements for the Ph.D. degree, Purdue University, January, 1967.

³ Present address: Department of Dairy Science, University of Wisconsin, Madison.