|
|
||||||||
University of Wisconsin, Madison 53706
Abstract
An in vitro and in vivo experiment was performed to determine the extent of movement of samarium (Sm), cerium (Ce), and lanthanum (La) from the original feedstuff upon which they were adsorbed to other feed particles. The rare-earth elements were demonstrated to be tenaciously bound to the particulate phase, with essentially none of the element occuring in the liquid phase. When Sm, Ce and La were adsorbed onto grain, 92.6% of the elements remained with the grain after a 24 hr incubation period in vitro. When Sm, Ce and La were adsorbed onto hay, 99.2% of the elements remained associated with the hay after a 24 hr incubation period.
Four rumen fistulated cows were fed Sm, Ce and La treated hay (1 g of element applied per .9 kg of hay) for 5 days. At the beginning of the sixth day, unmarked hay was fed and removed from the rumen every 6 hr for 24 hours. At 6, 12, 18 and 24 hr, 4.4, 5.8, 5.9 and 10.1% of the rare-earth elements on a ppm basis were detected on particulate fractions other than the one upon which they were originally placed. Possible reasons for the small amount of marker movement are discussed. Rare-earth elements can be used as multiple or simultaneous markers of ration ingredients as they pass through the digestive tract.
1 Research supported by the College of Agricultural and Life Sciences, the University of Wisconsin Graduate Research Committee, and by Federal Hatch Project 1891.
2 The authors would like to thank Richard J. Cashwell and Stephen M. Matusewic of the Nuclear Engineering Department at the University of Wisconsin for the neutron activation analysis.
3 Present address: Allied Mills Inc., Research and Development Center, P.O. Box 459, Libertyville, IL 60048.
This article has been cited by other articles:
![]() |
R. Worley, A. Clearfield, and W. C. Ellis Binding affinity and capacities for ytterbium(3+) and hafnium(4+) by chemical entities of plant tissue fragments J Anim Sci, December 1, 2002; 80(12): 3307 - 3314. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. C. Ellis, M. J. Wylie, and J. H. Matis Validity of specifically applied rare earth elements and compartmental models for estimating flux of undigested plant tissue residues through the gastrointestinal tract of ruminants J Anim Sci, October 1, 2002; 80(10): 2753 - 2758. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |