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 Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Moore, W. F. Articles by Webb, K. E. Search for Related Content PubMed PubMed Citation Articles by Moore, W. F. Articles by Webb, K. E., Jr.

Effect of Form and Level of Nitrogen on Magnesium Utilization

Virginia Polytechnic Institute and State University,² Blacksburg 24061

Abstract

TWO metabolism trials were conducted with 12 wether lambs to study the relative effects of two levels of crude protein (nitrogen) and two levels of non-protein nitrogen (urea) on magnesium utilization. The two levels of crude protein were approximately 10% and 32% (dry basis). At each level of protein, 0 and 35% of the crude protein was provided by urea. Ruminal ammonia-N, blood ammonia-N and blood urea levels were higher (P<.01) for the lambs fed the high-nitrogen rations than for those fed the low-nitrogen rations. Ruminal fluid pH was increased (P<.01) for the animals consuming the rations containing urea. There were no significant differences in apparent magnesium absorption between the four rations, indicating that high ruminal fluid ammonia levels did not interfere with magnesium absorption. Urinary magnesium excretion was higher and magnesium retention was lower (P<.01) for the animals consuming the high-nitrogen rations, and there were no significant differences due to the form of nitrogen in the rations.

There were no significant differences in calcium absorption between the four rations. Calcium retention was lower (P<.05) for the first and fourth periods for the high-nitrogen rations. Apparent phosphorus absorption was greater (P<.01) for the high-nitrogen rations during collection periods 1, 3 and 4. For period 1, phosphorus retention was higher (P<.01) for the high-nitrogen rations. When the rations contained urea there was a lower phosphorus absorption (P<.05) and retention (P<.05) during periods 1 and 3. Apparent potassium absorption was greater (P<.01) during periods 3 and 4 for the lambs fed the high-nitrogen rations. No significant differences were noted in blood serum calcium, magnesium, inorganic phosphorus or potassium levels due to treatment.

¹ Present address: Berry College, Mount Berry, Ga.

² Department of Animal Science.

This article has been cited by other articles:

				J. T. Schonewille, H. Everts, S. Jittakhot, and A. C. Beynen Quantitative Prediction of Magnesium Absorption in Dairy Cows J Dairy Sci, January 1, 2008; 91(1): 271 - 278. [Abstract] [Full Text] [PDF]