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The inorganic constituents of milk IV. Diffusible calcium and magnesium concentrations in goat's milk and the effect of starvation

Published online by Cambridge University Press:  01 June 2009

Ian H. L. Ormrod
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, Scotland
Carl Holt
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, Scotland
Phillip C. Thomas
Affiliation:
Hannah Research Institute, Ayr KA6 5HL, Scotland

Summary

The concentrations of diffusible Ca and Mg in milk diffusates from 3 goats were determined before, during and after a 2-d period of starvation. Free Ca-concentrations were determined by a murexide method and compared with values calculated from a detailed model of the ion equilibria. It was shown that diffusible Ca increased as citrate increased during fasting and both decreased after refeeding, but there was a difference of about half a day in the response curves, with citrate following Ca. The difference was accounted for mainly by a change in free Ca2+ concentration which in turn was related mainly to changes in milk pH. Diffusible Mg underwent changes similar to those of diffusible Ca.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1982

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References

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