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 Blake,, R. W. Articles by Richter, R. L. Search for Related Content PubMed Articles by Blake,, R. W. Articles by Richter, R. L.

Relationships between Distribution of Major Milk Proteins and Milk Yield¹

Department of Animal Science, Texas A&M University, College Station 77843

ABSTRACT

Daily yield and composition of casein and serum proteins of milks from Holstein and Jersey cows were studied during two 9-day periods of lactation to determine whether selection for milk yield influences distribution of total protein between casein and serum fractions. Casein number, defined as casein/total protein as percent, was the distribution criterion. Casein number of Holsteins was not associated with daily or mature equivalent yield of milk, estimated real producing ability, or United States Department of Agriculture Cow Index for milk yield. In early lactation, Jerseys had 4.7% more protein as casein than Holsteins. The intralactation repeatability of casein number for Holsteins was .31. Standard deviation of casein number due to cow was 2.3 and was worth $29.60/ 305-day lactation yielding 7483 kg milk.

¹ Technical article 15257 of the Texas Agricultural Experiment Station, College Station 77843, Project 2491, a contribution to Southern Regional Project, S-49, Genetic Methods of Improving Dairy Cattle for the South.