QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart 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 Ward, G. M. Articles by Reid, J. T. Search for Related Content PubMed Articles by Ward, G. M. Articles by Reid, J. T.

Mineral Metabolism Studies in Dairy Cattle

II. Effect of Calcium and Manganese and Other Trace Elements on the Metabolism of Lipids during Early Lactation¹

New Jersey Agricultural Experiment Station, Sussex, New Jersey

A study was made of the effects of Ca, Mn, and other mineral element supplementation upon the metabolism of lipids during the first 5 months of lactation of 8 Holstein and 4 Guernsey cows.

All groups excreted similar proportions of the total lipid intake, as measured by acid hydrolysis and CHCl₃ extraction, regardless of the mineral supplement received. Therefore the observed group differences relative to the smaller proportion of ether extractives lost in the feces of animals receiving supplemental Ca were attributed to an increased formation of soaps which were not measured in the feces of these animals because of the insolubility of soap in di-ethyl ether, and not to a more efficient lipid use. Although the ingestion of Ca tended to spare neutral fat and sterols, a corresponding increase was observed in the excretion of soaps and free fatty acids, resulting in a qualitative rather than a quantitative effect.

These data would indicate that the estimation of crude fat by the commonly employed ether extraction procedure is likely to be misleading in experiments involving the analysis of dairy cow feces.

Manuscript received 29 September 1947.