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 Wilson, L. L. Articles by Bair, L. G. Search for Related Content PubMed PubMed Citation Articles by Wilson, L. L. Articles by Bair, L. G.

Incidence of Intramammary Infections and Effects of Number of Lactations, Lactation Stage, Quarter and Calf Sex on Somatic Cell Content of Milk from Angus-Holstein F₁ Cows¹

The Pennsylvania State University, University Park 16802

Abstract

Quarter milk samples were collected from 44 Angus-Holstein F₁ cows ranging in age from 2 to 7 years. Mean calf age at first sampling was 26 days and ranged from 1 to 42 days. Eight foremilk samples were taken from each of the four quarters at approximately 28-day intervals throughout lactation. Bacteriologic examination, somatic cell counts (SCC) and California Mastitis Tests (CMT) were conducted on each sample. Streptococcus agalactiae was not isolated from any milk sample. One quarter of each of two cows had chronic Staphylococcus aureus infections. Streptococcus dysgalactiae was the apparent cause of severe mastitis in one quarter in mid-lactation. Number of lactations did not significantly influence adjusted 205-day weight, log SCC or CMT. Log SCC was significantly (P<.01) affected by lactation stage and mean SCC was greatest at the first sampling, declined, and then increased at the seventh and eighth samplings. Quarter significantly (P<.01) affected log SCC and CMT, but calf sex did not significantly influence log SCC or CMT.

¹ Approved by the Director of the Pennsylvania Agricultural Experiment Station as Paper No. 3893; number assigned Dec. 14, 1970.

² The authors are grateful to personnel of the State Correctional Institution at Rockview, Pennsylvania Dept. of Justice, for granting permission for the use of animals and facilities. Acknowledgement is also given to the Leon Falk Family Trust for grants-in-aid toward the conduct of this study.

This article has been cited by other articles:

				C. A. Lents, R. P. Wettemann, M. J. Paape, M. L. Looper, and D. S. Buchanan Effects of dry cow treatment of beef cows on pathogenic organisms, milk somatic cell counts, and calf growth during the subsequent lactation J Anim Sci, March 1, 2008; 86(3): 748 - 755. [Abstract] [Full Text] [PDF]