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 Davis, C. L. Articles by Rust, J. W. Search for Related Content PubMed Articles by Davis, C. L. Articles by Rust, J. W.

An Evaluation of Urea and Dicyandiamide for Milking Cows¹

Dairy Section, University of Kentucky, Lexington

Abstract

Twenty-four lactating dairy cows were used in two 56-day experiments to further evaluate the use of urea and dicyandiamide in the concentrate mixture of milking cows. Urea and dicyandiamide replaced approximately one-third of the nitrogen in a basal ration when soybean oil meal was used as the source of nitrogen. A fourth concentrate ration was included in each experiment which contained one-third less protein than the other rations. Alfalfa hay and corn silage were fed as roughages in Experiment I, and corn silage and timothy-red clover hay were used during Experiment II. During Experiment II all cows were fed below the minimum recommended amount of protein.

No significant differences in milk production in either experiment between the four rations were observed. The cows fed the low-protein ration and the ration containing dicyandiamide declined in milk production more than cows fed rations containing either soybean oil meal or urea. No differences in body weight changes or feed consumption were observed.

The ration being fed appeared to influence the level of urea nitrogen in both the blood and milk. Cows fed the low-protein and dicyandiamide rations tended to have lower levels of urea nitrogen in both the blood and milk than cows fed the rations containing either soybean oil meal or urea. No significant differences were observed in the digestibility of feed nutrients of the various rations. Evidence was obtained in Experiment II that the addition of non-protein nitrogen to the low-protein ration caused slightly better average utilization of the feed nutrients, but the differences were not significant.

¹ The investigation reported in this paper is in connection with a project of the Kentucky Agricultural Experiment Station and is published by permission of the Director. The authors express appreciation to the Allied Chemical Dye Corporation, New York, N. Y., for supplying the urea, and to the American Cyanamid Company, Lederle Laboratories Division, Pearl River, N. Y. for supplying the dicyandiamide.

² Present address: Dairy Science Department, University of Illinois, Urbana.

³ Present address: Dairy Department, Michigan State University, East Lansing.