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 Bath, D. L. Articles by Ronning, M. Search for Related Content PubMed Articles by Bath, D. L. Articles by Ronning, M.

Voluntary Alfalfa Hay Water Intake by Lactating Dairy Cows Fed Varying Concentrate Amounts

Animal Science Extension

G. A. E. Gall and M. Ronning

Department of Animal Science, University of California, Davis 95616

ABSTRACT

Voluntary hay wafer intake of 20 first-lactation Holstein cows fed 20, 35, 50, 65, or 80% of their estimated net energy requirements as a concentrate mix was measured during a 36-wk feeding trial. Mean hay wafer dry matter intake declined .78 kg for each 1.0 kg of concentrate dry matter consumed by the cows. However, concentrate intake per se accounted for only 43% of the variability in voluntary hay wafer intake.

Multiple regression models which included as variables concentrate treatment, maintenance net energy requirement, milk energy, and week of test accounted for 73% of the variation in voluntary hay wafer intake.

Depressed milk fat percentage occurred consistently among higher producing cows receiving 50% or more of their energy requirements as a concentrate mix whereas lower producing cows gave milk with normal fat composition regardless of ration. Milk fat percentage was normal from all cows fed 20 to 35% of their energy requirements as concentrates.