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 Miller, R. H. Articles by Creegan, M. E. Search for Related Content PubMed Articles by Miller, R. H. Articles by Creegan, M. E.

Feed Consumption Differences Among Lactating Cows

Animal Science Research Division, ARS, USDA, Beltsville, Maryland 20705

ABSTRACT

Variation among cows in grain, forage, and total feed consumption was studied with 548 Holstein daughter-dam pairs in a single herd over 19 years. Cows were fed alfalfa hay and silage ad libitum, and a 15% protein grain mixture was provided to supply the difference between 115% of Morrison's net energy requirements and the estimated energy consumed in forage. heritabilities and their standard errors for forage, grain, and total estimated net energy consumption were .19 ± .09, .26 ± .09, and .42 ± .10. The genetic correlation between grain consumption and milk yield was 1.0 due to the precise allocation of grain according to each cow's production. Genetic and phenotypic correlations between forage consumption and milk yield were positive but much less. Forage consumption was negatively related to gross feed efficiency. The feeding regime increased variation among cows in yield by varying the forage:grain ration. Cows varied less in total intake than in either forage or grain consumption.