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 Miller, J. K. Articles by Swanson, E. W. Search for Related Content PubMed Articles by Miller, J. K. Articles by Swanson, E. W.

Some Factors Affecting Iodine Secretion in Milk¹

Agricultural Research Laboratory of The University of Tennessee, Oak Ridge²

ABSTRACT

A series of experiments was conducted to study the manner in which iodine enters cows' milk: (a) Eight cows averaging 23.2 lb milk daily were paired with their identical twins in later lactation averaging 10.7 lb. Iodine¹³¹ was administered intravenously followed by seven-day collection periods; (b) milk secretion was stopped in the left udder halves of eight cows by allowing a 24-hr accumulation of milk, and the right halves were milked prior to intravenous administration of I¹³¹. Left and right udder halves were milked at 8- and 32-hr intervals thereafter for six days; (c) Iodine¹³¹ was infused into the gland cisterns of six cows after the morning milking. Absorption of administered I¹³¹ from the mammary gland into the blood stream was estimated from the percentage of the dose recovered in the milk during subsequent milkings.

Results indicate that iodide passes easily in both directions between the cow's mammary gland and blood, and that it can enter the milk independent of milk secretion. Protein-bound iodine did not appear to transfer between blood and milk in either direction. It is indicated that iodide enters the cow's udder passively (regardless of secretory activity), but that once it is in the milk-collecting spaces, a portion of the iodine is bound in some manner and is not available for resorption. The greater iodine secretion of higher-yielding cows is related primarily to their greater volume of milk.

¹ This manuscript is published with the permission of the Director of the University of Tennessee Agricultural Experiment Station, Knoxville.

² Operated by the Tennessee Agricultural Experiment Station for the U. S. Atomic Energy Commission under Contract No. AT-40-1-GEN-242.