Digestion and Digesta Passage in the Brushtail Possum, Trichosurus Vulpecula (Kerr).

Abstract

Digestion and digesta passage rate were studied in brushtail possums (Trichosurus vulpecula) fed on semipurified diets of 2 different fibre values. Increasing fibre in the diet from 17 to 41% neutral detergent fibre (NDF) depressed digestibility of DM (P<0.01), energy (P<0.001) and NDF (P<0.05). Within the high-fibre diets, but not the low-fibre diets, there were negative correlations between apparent digestibility of DM and DM intake (P<0.005) and between NDF digestibility and DM intake (P<0.001). Caecectomy had no effect on intake or digestion of DM or fibre. The average mean retention time in intact animals was 64 h for fluid and 71 h for particulate digesta. Caecectomy increased the mean retention time of fluid to 120 h (P<0.025) and of particles to 125 h (P<0.01). This increase in retention time was used to explain the lack of any significant effect of caecectomy on fibre digestibility. There was no significant differentiation in passage rate of fluid and particulate digesta. Results are discussed in relation to the role of the caecum in digestion in the brushtail possum.