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 Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wilton, J. W. Articles by Roberts, S. J. Search for Related Content PubMed PubMed Citation Articles by Wilton, J. W. Articles by Roberts, S. J.

Genetic and Environmental Aspects of Udder Infections

¹ Department of Animal Science
, and² Department of Veterinary Medicine and Obstetrics, Cornell University, Ithaca, New York 14850

ABSTRACT

Information on the presence or absence of bacterial infections and abnormal secretions in each quarter of cows in their initial survey on the New York State Veterinary College Mastitis Program was used to obtain several criteria of udder infection. Year-season and stage of lactation effects were statistically significant for several criteria of infection in first, second, and later lactation groups but did not explain much of the variation in any infection criterion. Age within first and second lactation group also accounted for little of the variation in infection although age within later lactations accounted for up to 5% of the variation in some criteria.

Heritabilities from sire components of variance were all low for first, second, and later lactation cows. Heritabilities from daughter-dam regression were low for first and second lactation cows but moderately high for later lactation cows. Regression of second lactation infections on first lactation infections, later lactation infections on first lactation infections, and later lactation infections on second lactation infections were moderately high. Heritabilities from sire components of variance were not increased by using two surveys per cow, by using only herds with high incidence of infections, or by using only sires with large numbers of daughters. Phenotypic relationships between milk yield and infections were all low. Some of the overall measurements of infection on later lactation cows had genetic correlations of approximately .3 with first lactation milk production.

³ Present address: Department of Animal Science, University of Guelph, Guelph, Ontario. Financial assistance Eastern Artificial Insemination Cooperative, Ithaca, New York, for key punch support is gratefully acknowledged.

This article has been cited by other articles:

				B. S. Sharma, G. B. Jansen, N. A. Karrow, D. Kelton, and Z. Jiang Detection and characterization of amplified fragment length polymorphism markers for clinical mastitis in canadian holsteins. J Dairy Sci, September 1, 2006; 89(9): 3653 - 3663. [Abstract] [Full Text] [PDF]