![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
Department of Nutrition, University of California, Davis, CA 95616
The concentrations of iron, copper, zinc, manganese, calcium and magnesium, as well as protein, carbohydrate and fat, were anayzed in rat milk during the course of lactation in rats fed a purified diet. As serial milking has been demonstrated to affect milk composition (1), lactating rats were milked only once at various times from days 0 to 28 after parturition. Concentration of iron decreased rapidly from 9 to 5 µg/ml during the 1st week of lactation and changed little thereafter. Similarly, copper concentration decreased considerably in early lactation, from 9 to 2 µg/ml, but then remained constant. Zinc concentration did not decrease during the 1st week of lactation, but dropped from 14 µg/ml in the 2nd week of lactation to 8–10 µg/ml in mature milk. Manganese was unique as its concentration decreased during the early days of lactation, from 0.3 to 0.1 µg/ml, with a subsequent rise in late lactation back to 0.3 µg/ml. Calcium and magnesium concentrations increased somewhat in early lactation and decreased slightly in later lactation, but the changes were fairly small as compared to the trace elements. Developmental patterns for protein, carbohydrate and fat were not very pronounced, although protein and carbohydrate increased somewhat in early lactation and later decreased. These data demonstrate that the nutrient intake of the suckling changes markedly during the early neonatal period. These changes should be taken into account in evaluating data on the trace element composition of tissues of suckling rats.
KEY WORDS: • milk composition • lactation • trace elements
1 Supported in part by NIH Research grants HD-01743 and HD-12547 from the National Institute of Child Health and Human Development.
2 Present in part at the Annual Meeting of the American Institute of Nutrition, Federation of American Societies for Experimental Biology, Anaheim, CA, April 1980; Fed. Proc. 39, 903.
3 Postdoctoral Fellow, National Research Service Award DE-07001, from the National Institute of Dental Research, NIH.
4 To whom reprint requests should be sent.
Manuscript received 23 June 1980.
This article has been cited by other articles:
|
|
 |
|
  T. S. McMullin, E. R. Lowe, M. J. Bartels, and M. S. Marty Dynamic Changes in Lipids and Proteins of Maternal, Fetal, and Pup Blood and Milk during Perinatal Development in CD and Wistar Rats Toxicol. Sci., October 1, 2008; 105(2): 260 - 274. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. T. Johnson and C. M. Anderson Cardiac Cytochrome c Oxidase Activity and Contents of Subunits 1 and 4 Are Altered in Offspring by Low Prenatal Copper Intake by Rat Dams J. Nutr., July 1, 2008; 138(7): 1269 - 1273. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. L. Kelleher and B. Lonnerdal Mammary gland copper transport is stimulated by prolactin through alterations in Ctr1 and Atp7A localization Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2006; 291(4): R1181 - R1191. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. C. Dorman, A. M. McElveen, M. W. Marshall, C. U. Parkinson, R. A. James, M. F. Struve, and B. A. Wong Tissue Manganese Concentrations in Lactating Rats and Their Offspring Following Combined in Utero and Lactation Exposure to Inhaled Manganese Sulfate Toxicol. Sci., March 1, 2005; 84(1): 12 - 21. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W.-I. Leong, C. L. Bowlus, J. Tallkvist, and B. Lonnerdal DMT1 and FPN1 expression during infancy: developmental regulation of iron absorption Am J Physiol Gastrointest Liver Physiol, December 1, 2003; 285(6): G1153 - G1161. [Abstract] [Full Text] [PDF]
|
|
