The free amino acids occurring in the blood plasma and rumen liquor of the sheep.

The concentrations of free amino acids occurring in the rumen liquor and blood plasma of the sheep have been determined. The concentrations in the blood plasma were lower than those found in monogastric animals. After feeding, the free amino acids in the plasma increased 2 to 10-fold and those in the rumen liquor up to 100-fold. These elevated concentrations were maintained for between 1 and 3 hr.