The suitability of a faecal suspension of sheep as inocula for the estimation of utilizable crude protein of feeds by in vitro incubation

摘要

The objective of the experiments was to study the suitability of using a faecal suspension of sheep for the estimation of the utilizable crude protein (uCP) of feeds for sheep by an in vitro incubation. Twenty-four single feeds and eight feed mixtures were used as incubation substrates. In Experiment 1, the gas production after the in vitro incubation with rumen fluid or with a faecal suspension of a sheep were compared using the Hohenheim gas test. It was found that there were significant linear regression between the 24, 48 and 72 h gas production with rumen fluid and those with faecal suspensions of 35, 50, 100 and 150 g wet faeces of sheep (which were 18.6, 23.5, 52.0 and 70.5 g faeces DM, respectively) per hire McDougall's buffer (P < 0.0001). The highest regression coefficient (r(2)) Was Calculated between the gas production after inoculation with a suspension of 100 g wet faeces per hire McDougall's buffer (x, ml.200 mg(-1) feed DM) for 48 h and the gas production after inoculation with rumen fluid (y, ml.200 mg(-1) feed DM) for 24 h: