Rate of passage of digesta in sheep

Abstract

1. The rates of passage of markers of fluid and particulate digesta through the sheep alimentary tract have been described mathematically in single-injection experiments by analysing the concentration curves of marker excretion in faecal dry matter and then predicting these concentrations by means of an equation containing two exponential terms. Three components related to this equation are a transit time for digesta in the intestines, a half-time of marker in the reticulo-rumen and a half-time tentatively associated with the passage of marker through the caecum and proximal colon. With this approach no surgical interference with an animal is required to obtain meaningful information about gut function.2. Abomasal cannulation did not affect the rate of passage of 51Cr EDTA through the gut.3. The mean half-times (T1/2) for 51Cr EDTA in the reticulo-rumen and hind-gut, respectively, were 646 and 236 min for a roughage diet and 890 and 607 min for a diet consisting mainly of wheat grain, both diets providing approximately the same amounts of digestible dry matter. These results indicated that the changes in half-times were proportionately much greater in the caecum and proximal colon than in the reticulo-rumen. The mean transit time of marker through the digestive tract also increased from 721 to 1345 min when the concentrate diet was given.4. The complex of chromium-51 with EDTA was excreted faster in faeces than cerium-144–praseodymium-144 when both were given together as a single injection into the reticulorumen. This was caused mainly by differential rates of elimination of water and particulate matter from the reticulo-rumen.

Chelating agents for radiolanthanides: Applications to imaging and therapy

“…The 144 Ce/ 144 Pr system has found application as a radiotracer in nutritional science more than 30 years ago, where the elimination of the Ln-EDTA complex in sheep was found to be more rapid than the corresponding 51 Cr system. 82 The complex 51 Cr-EDTA was excreted faster in faeces than 144 Ce/ 144 Pr when both were given together as a single injection into the reticulorumen. In fundamental studies, Sherry and co-workers previously reported the thermodynamic properties of Ln(III) complexes of common triaza and tetraaza macrocycles, including EDTA, NOTA, DTPA and DOTA (Fig.…”

Inferred Mixing Compartments in the Sheep's Digestive Tract

“…Marker passage studies showed that on maize cob leaves a significant part of the flow pattern, normally associated with mixing in the hindgut, originated anterior to the ileum while on lucerne it did not show the same pattern.Key words: Sheep, digesta, mixing compartments, marker passage Digesta flow kinetics in the whole digestive tract was first described by Blaxter et al (1956) and later substantiated by Grovum and Williams (1973) For personal use only. …”

“…Key words: Sheep, digesta, mixing compartments, marker passage Digesta flow kinetics in the whole digestive tract was first described by Blaxter et al (1956) and later substantiated by Grovum and Williams (1973) For personal use only.…”

Comparaison de différents modèles d'ajustement des courbes d'excrétion fécale des marqueurs du transit

“…Summary ― Seventy nine fecal excretion curves of rare earth were adjusted with 3 published models (Grovum and Williams, 1973;Ohanoa et al, 1985;Siddons et al, 1983 …”

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Summary ― Seventy nine fecal excretion curves of rare earth were adjusted with 3 published models (Grovum and Williams, 1973; Ohanoa et al, 1985;Siddons et al, 1983). The models provided statistically similar estimations of particulate tumover in the first compartment and mean retention time.

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