Published online by Cambridge University Press: 27 March 2009
Experiments were done on three sheep fed several diets to determine the usefulness of the marker 51Cr-EDTA in the caecum of the sheep to study changes in weight of digesta and its turnover time. The activity of the marker decreased exponentially with time, indicating that it had mixed with a pool of digesta. Variation in the results was attributed mainly to the slowness of mixing and to the periodic nature of filling with digesta from the ileum.
Most estimates of weight of digesta were compatible with the digesta being contained in the caecum and the proximal colon but in one sheep some estimates obtained by one method of calculation were so large as to be unrealistic. Both the estimated weight and the rate of turnover of digesta varied with the weight of the sheep and the level of food intake.