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 Swanson, E. W. Articles by Longmire, D. B. Search for Related Content PubMed PubMed Citation Articles by Swanson, E. W. Articles by Longmire, D. B.

Effect of Gestation and Dry Period on Deoxyribonucleic Acid and Alveolar Characteristics of Bovine Mammary Glands

Department of Dairying, University of Tennessee, Knoxville

ABSTRACT

Udders of 21 lactating and 26 dry cows were analyzed for deoxyribonucleic acid (DNA) concentration and amount. Right and left halves of 21 cows were dried off at different times to give comparisons between dry periods of 15, 45, 60, and 75 days. Udders of five dry cows with dry periods of 8 and 48 days for right and left halves, respectively, were obtained about a week before calving. Histological sections of 26 udders were used to record alveolar density and surface area. The correlation coefiicient between total DNA and milk yield per half udder (r = 0.34) was small but statistically significant (P < .05). Concentration of DNA and alveoli increased in dry udders compared to prepartum and laxtating udders. Involution of udders of nonpregnant or early gestation cows was evidenced by reductions in fresh weight, dry weight, alveolar surface area, and DNA. In prepartum half udders, six weeks' difference in dry period did not significantly affect dry weight, DNA, or alveolar concentration. Lack of interference with either involution or alveolar development in the udder due to short dry periods indicates that subsequent subnormal lactation may be due to subnormal function rather than structure.

¹ Present address: Department of Dairy Science, Clemson University, Clemson, South Carolina.

This article has been cited by other articles:

				E. L. Annen, C. M. Stiening, B. A. Crooker, A. C. Fitzgerald, and R. J. Collier Effect of continuous milking and prostaglandin E2 on milk production and mammary epithelial cell turnover, ultrastructure, and gene expression J Anim Sci, May 1, 2008; 86(5): 1132 - 1144. [Abstract] [Full Text] [PDF]

				A. C. Fitzgerald, E. L. Annen-Dawson, L. H. Baumgard, and R. J. Collier Evaluation of Continuous Lactation and Increased Milking Frequency on Milk Production and Mammary Cell Turnover in Primiparous Holstein Cows J Dairy Sci, December 1, 2007; 90(12): 5483 - 5489. [Abstract] [Full Text] [PDF]

				E. L. Annen, A. C. Fitzgerald, P. C. Gentry, M. A. McGuire, A. V. Capuco, L. H. Baumgard, and R. J. Collier Effect of Continuous Milking and Bovine Somatotropin Supplementation on Mammary Epithelial Cell Turnover J Dairy Sci, January 1, 2007; 90(1): 165 - 183. [Abstract] [Full Text] [PDF]