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Free amino -nitrogen used as a monitor for the uptake and movement of amino acids in sheep

Published online by Cambridge University Press:  27 March 2009

Margaret I. Chalmers
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
I. Grant
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
Maureen G. Annand
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
F. White
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB

Summary

Free amino -N estimations were used to monitor the movement of amino acids in the vascular system of sheep. The net uptake of free amino-N by portal drained viscera was measured in whole blood and compared with the net gain in the plasma flow.

In normally fed sheep eating dried grass, lucerne or silage the net gain of free amino -N in the plasma of portal blood contributed less than 80% to the total uptake in whole blood. When the protein component of the diet was added into the abomasum (casein supplement to a low nitrogen basal ration) the plasma contribution to the net gain in portal blood averaged 95%.

The results suggest that the cells as well as the plasma are involved in the transport of amino acids in blood and that in ruminants all amino acids have to be measured in blood for a quantitative calculation of the absorption from portal drained viscera.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1977

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