Rate of Utilization of Acetate in the Ruminant. ∗

Abstract

Summary

Yearling lambs which had been trained to wear a face mask were used in experiments to study the metabolism of acetate. The rate of turnover of acetate in the body, that is, rate of acetate influx from the rumen into the blood, its transfer from the blood into other tissues, its conversion into other compounds, and its subsequent appearance as CO₂ were measured in 2 sheep. Acetate- 1-C¹⁴ disappeared from the body pool with an extremely short turnover time, approximately 3 min., while 50% recovery as expired CO₂ required well over an hour. These results indicate the formation of intermediary compounds which turn over much more slowly than body acetate. The calculated acetate flux during the fourth hour after feeding was 9.7 and 10.9 mM/min/sheep, equivalent to 35 and 39 g of acetic acid/hr.