skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration

Abstract

Four multiple-cannulated steers (340 kg) were used in a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments. Steers were fed a diet of 50% ground hay and 50% concentrate at two intakes (1.4 and 2.1% of BW), with urea and /sup 15/N-enriched ammonium sulfate infused continuously into the rumen at .4 or 1.2% of diet DM. Ratios of purines and diaminopimelic acid-N to N in fluid-associated and particulate-associated bacteria and in protozoa were similar among treatments but were lower for protozoa than for bacteria. Diaminopimelic acid-N:N was higher for fluid-associated vs. particulate-associated bacteria. Enrichment of /sup 15/N was similar between bacteria among treatments and was 30% lower for protozoa. Turnover rates of /sup 15/N in bacteria, NH/sub 3/N, and non-HN/sub 3/N pools were faster for steers infused with 1.2 than those infused with .4% urea, indicating less efficient usage of ammonia with higher urea. A method is described to estimate the proportion of duodenal nitrogen comprising bacterial and protozoal nitrogen.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Univ. of Illinois, Urbana
OSTI Identifier:
5341178
Resource Type:
Journal Article
Journal Name:
J. Dairy Sci.; (United States)
Additional Journal Information:
Journal Volume: 70:11
Country of Publication:
United States
Language:
English
Subject:
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; 60 APPLIED LIFE SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; CATTLE; METABOLISM; NITROGEN; BACTERIA; DIET; INTAKE; NITROGEN 15; NUTRITION; PROTOZOA; TRACER TECHNIQUES; UREA; AMIDES; ANIMALS; CARBONIC ACID DERIVATIVES; DOMESTIC ANIMALS; ELEMENTS; INVERTEBRATES; ISOTOPE APPLICATIONS; ISOTOPES; LIGHT NUCLEI; MAMMALS; MICROORGANISMS; NITROGEN ISOTOPES; NONMETALS; NUCLEI; ODD-EVEN NUCLEI; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; RUMINANTS; STABLE ISOTOPES; VERTEBRATES; 560300* - Chemicals Metabolism & Toxicology; 553005 - Agriculture & Food Technology- Animal Husbandry- (1987-); 550501 - Metabolism- Tracer Techniques

Citation Formats

Firkins, J L, Berger, L L, Merchen, N R, Fahey, Jr, G C, and Mulvaney, R L. Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration. United States: N. p., 1987. Web. doi:10.3168/jds.S0022-0302(87)80290-4.
Firkins, J L, Berger, L L, Merchen, N R, Fahey, Jr, G C, & Mulvaney, R L. Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration. United States. doi:10.3168/jds.S0022-0302(87)80290-4.
Firkins, J L, Berger, L L, Merchen, N R, Fahey, Jr, G C, and Mulvaney, R L. Sun . "Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration". United States. doi:10.3168/jds.S0022-0302(87)80290-4.
@article{osti_5341178,
title = {Ruminal nitrogen metabolism in steers as affected by feed intake and dietary urea concentration},
author = {Firkins, J L and Berger, L L and Merchen, N R and Fahey, Jr, G C and Mulvaney, R L},
abstractNote = {Four multiple-cannulated steers (340 kg) were used in a 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments. Steers were fed a diet of 50% ground hay and 50% concentrate at two intakes (1.4 and 2.1% of BW), with urea and /sup 15/N-enriched ammonium sulfate infused continuously into the rumen at .4 or 1.2% of diet DM. Ratios of purines and diaminopimelic acid-N to N in fluid-associated and particulate-associated bacteria and in protozoa were similar among treatments but were lower for protozoa than for bacteria. Diaminopimelic acid-N:N was higher for fluid-associated vs. particulate-associated bacteria. Enrichment of /sup 15/N was similar between bacteria among treatments and was 30% lower for protozoa. Turnover rates of /sup 15/N in bacteria, NH/sub 3/N, and non-HN/sub 3/N pools were faster for steers infused with 1.2 than those infused with .4% urea, indicating less efficient usage of ammonia with higher urea. A method is described to estimate the proportion of duodenal nitrogen comprising bacterial and protozoal nitrogen.},
doi = {10.3168/jds.S0022-0302(87)80290-4},
journal = {J. Dairy Sci.; (United States)},
number = ,
volume = 70:11,
place = {United States},
year = {1987},
month = {11}
}