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 Google Scholar Google Scholar Articles by Peeters, G. Articles by Verschooten, F. Search for Related Content PubMed PubMed Citation Articles by Peeters, G. Articles by Verschooten, F.

Electromagnetic Blood Flow Recording and Balance of Nutrients in the Udder of Lactating Cows¹

Department of Physiology, Veterinary Faculty of the University of Ghent, Casinoplein 24, B-9000 Ghent, Belgium

Abstract

An electromagnetic method was adapted to quantitatively measure blood flow through an external pudic artery of the udder in lactating cows during several months. Blood flow through the ipsilateral external pudic vein was blocked while blood was taken from a subcutaneous abdominal vein.

Blood flow to milk yield ratio amounted to a mean value of 507:1 in three cows. Peak milk yield occurred before the time of our experiments. There was a high correlation (r = .73) between mammary arterial blood flow and milk yield. Arterio-venous differences (AV) across the udder demonstrated that essential amino acids (EAA) were taken up by the mammary gland in sufficient amounts to account for the EAA secreted as milk protein. Uptake of valine, isoleucine, lysine and particularly that of arginine was in excess of that for milk protein synthesis. There was a highly significant correlation (P<.01) between AV differences of several amino acids and their corresponding arterial concentrations. Uptake of glucose was 19% higher than could be accounted for by secretion as milk lactose. Uptake of plasma triglycerides (TG) accounted for 45% of milk TG. The majority of the TG taken up by the udder was derived from the low density lipoprotein (LDL) fraction

¹ This work was supported by grants from the Institut pour l'Encouragement de la Recherche Scientifique dans l'Industrie et l'Agriculture. The authors gratefully acknowledge Professor Dr. W. Welvaert of the Department of Phytopathology and Phytovirology of the University of Ghent, in whose laboratory the ultra-centrifugal analyses were carried out. They also acknowledge Dr. C. Burvenich, Mrs. M. Onghena-Anaf, Mrs. L. De NeveVan Lancker, Mrs. G. Vranken-Verhelst and Mrs. M. Buelens- Van Haute for skilled technical assistance.

² Laboratory of Veterinary Physiology, State University Centre of Antwerp.

³ Laboratory of Chemical Analysis of Food from Animal Origin, Veterinary Faculty of the University of Ghent.

⁴ Department of Surgery, Veterinary faculty of the University of Ghent.