Rate of passage of digesta in sheep

Abstract

1. Sheep were given 800 g lucerne chaff/d and the mean half-times of cerium-144 – praseodymium-144 and the complex of chromium-51 with EDTA were 811 and 604 min in the reticulo-rumen, 37 and 17 min in the abomasum and 413 and 406 min in the caecum and proximal colon respectively. The average time available for digestion and absorption in the abomasum was therefore very short relative to that in the other two organs.2. The half-times of the markers also indicated that particulate matter and water had different rates of turn over in the reticulo-rumen and abomasum but not in the caecum and proximal colon.3. Evidence is presented which suggests imperfect mixing of the digesta in the caecum and proximal colon.