JDS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Journal of Dairy Science Vol. 80 No. 9 2149-2155
© 1997 by American Dairy Science Association ®
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Bethard, G. L.
Right arrow Articles by McGilliard, M. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bethard, G. L.
Right arrow Articles by McGilliard, M. L.

Effect of Rumen-Undegradable Protein and Energy on Growth and Feed Efficiency of Growing Holstein Heifers

G. L. Bethard 1, R. E. James 1, and M. L. McGilliard 1

1 Department of Dairy Science, Virginia Agriculture Experiment Station, College of Agriculture and Life Sciences, Virginia Polytechnic Institute and State University, Blacksburg 24061-0315

Thirty-two Holstein heifers were used to determine the effect of energy and rumen-undegradable protein (RUP) on growth and feed efficiency. Treatment diets were in a 2 x 2 factorial consisting of two energy concentrations (supporting 0.6 or 0.9 kg of average daily gain) and two percentages of RUP (30 or 50% of crude protein). Isonitrogenous diets based on corn silage, alfalfa silage, orchardgrass hay, corn, soybean meal, blood meal, and minerals were fed. Treatment diets were fed until 385 d of age, constituting phase 1 of the trial. During phase 2 (until calving), heifers were housed together and fed a common diet for 0.7 kg of average daily gain. Dry matter intake (kilograms per day) during phase 1 was 4.46, 5.42, 7.38, and 5.95 for heifers fed low energy and low RUP, low energy and high RUP, high energy and low RUP, and high energy and high RUP diets, respectively. Average daily gain (kilograms) during phase 1 was 0.62, 0.74, 1.01, and 0.96, respectively. Dry matter intake and gain were higher for heifers receiving high energy diets. Dry matter efficiency was higher for heifers fed high energy and high RUP diets. Apparent total digestible nutrient efficiency was higher for heifers fed high RUP diets. Average daily gain during phase 2 was 0.53, 0.43, 0.33, and 0.50 kg, respectively. Overall average daily gain was not affected by energy or RUP levels during phase 1 because the slow growth of heifers during phase 1 was compensated by faster growth during phase 2.

Key Words: dairy heifer • rumen-undegradable protein • energy • average daily gain

Submitted on August 21, 1995
Accepted on April 11, 1997




This article has been cited by other articles:


Home page
 J DAIRY SCIHome page
G. I. Zanton, M. T. Gabler, and A. J. Heinrichs
Manipulation of Soluble and Rumen-Undegradable Protein in Diets Fed to Postpubertal Dairy Heifers
J Dairy Sci, February 1, 2007; 90(2): 978 - 986.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1997 by the American Dairy Science Association ®.