Abstract
In order to examine the practical technique of the chromogen-chromic oxide double indicator method for estimating forage in grazing cattle, several experiments were performed and the following results were obtained. 1) Chromogens were almost completely recoverd from the dried feces by the extraction starting from one gram of sample with 3l of 35% acetone for 90 minutes continuously in a Buchner funnel. 3) There were little differences between dried and fresh feces samples in the extracting rate of chromogen and in the estimated digestibility of dry matter. 3) About 99% of supplied chromic oxide was recovered from the feces sample collected for 3 days after 8 day-prefeeding. 4) Using cows receiving 40kg of Italan ryegrass soilage, forage intake was estimated by the chromogen-chromic oxide double indicator method, and it was found that the estimated value was statistically not different from the observed one.
