The evaluation of an improved artificial rumen technique for the study of rumen fermentation

Abstract

1. An improved artificial rumen apparatus of the dialysis type with multiple fermentation units was built and a method for its operation was evolved. Biochemical criteria of validity were used and particular reference was made to the molar percentage of the volatile fatty acids produced.2. It was found that the apparatus was best used in a comparative manner, to measure treatment differences produced between individual fermentation units.3. A series of experiments was carried out to measure the effects of a range of dietary treatments on rumen fermentation. In each case anin vivocomparison was also made using a cow with a permanent rumen fistula.4. Correlation coefficients for treatment differences of 0·43 and 0·46 were found for ammonia T.V.F.A., and 0·73, 0·90 and 0·70 for the molecular proportions of acetic, propionic and butyric all the latter being significant.5. The results were discussed with particular reference to the advantages and limitations of apparatus and the most suitable application of technique.