Body composition in vivo. V. The use of antipyrine and N-acetyl-4-aminoantipyrine for the estimation of gut water in living ruminants

Abstract

The differences between the simultaneously determined antipyrine and N-acetyl-4-aminoantipyrine spaces underestimated total gut water in ruminants; measurements made on seven sheep and 13 goats, which had been deprived of feed and water for 48 hr, were so variable that they could not be used to predict the volume of water in the gut. The variability encountered appeared to be due not only to the differing quantities of the compounds which appeared in the rumen, but also to the fact that their concentrations in the gut increased with time following their intravenous injection.

These compounds cannot be used to measure the total intraluminal water, with precision, in ruminants.