QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend 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 HOLMES, W. N. Articles by STEWART, D. J. Search for Related Content PubMed PubMed Citation Articles by HOLMES, W. N. Articles by STEWART, D. J.

Journal of Experimental Biology 48,487-508 (1968)
Published by Company of Biologists 1968

The Patterns of Renal Electrolyte Excretion in the Duck (Anas Platyrhynchos) Maintained on Freshwater and on Hypertonic Saline

W. N. HOLMES ¹, G. L. FLETCHER ¹, and D. J. STEWART ¹

¹ Department of Biological Sciences, University of California, Santa Barbara, California 93106

1. The renal excretion of water and electrolytes was examined in starved ducks maintained on fresh water and on hypertonic saline containing 284 mM/1. NaCl and 6.0 mM/l. KCl.

2. No significant differences were observed in the urine flow, glomerular filtration rate, renal plasma flow and the excretory rates of K⁺, NH₄⁺ and inorganic phosphate between these two groups of birds.

3. The excretory rates of Na⁺, Cl^- and Ca²⁺ were significantly higher in saline-maintained birds than in the freshwater-maintained birds.

4. NH₄⁺ appeared to be a major cationic component which occupied over half of the available osmotic space in the urine of both the freshwater-maintained and saline-maintained birds.

5. In saline-maintained birds the excretion of K⁺ and inorganic phosphate appeared to be independent of the available osmotic space in the urine whereas the excretion of Na⁺ and Cl^- appeared to be very dependent upon this factor.

6. These observations suggest that the kidneys of the saline-maintained bird constitute the primary pathway for the excretion of K⁺, NH₄⁺ and inorganic phosphate, and that with respect to the excretion of Na⁺ they constitute a relatively minor pathway.

Note:

This work was supported by research grants to W.N.H. from the National Science Foundation (grant no. GB 3896) and the Committee on Research, University of California.

N.D.E.A. (Title IV) pre-doctoral fellow.