Source of Nitrogen for Rumen Microbes

Abstract

Abstract In vitro technique was used to elucidate the effect of different nitrogen sources on the growth of rumen microbes. The results showed that the digestibility of cellulose with soybean and casein as nitrogen source was higher than all other nitrogen sources used in this experiment. The digbestibility of cellulose with polypeptides as nitrogen source was higher than with glutathione, casein hydrolysate, amino acid mixture and urea. The digestibility of cellulose with urea was very low for all levels of nitrogen. The digestibility of starch with urea was highest at 1.00% level of nitrogen and declined at further addition. The results showed no clear difference between nitrogen sources with starch as substrate. With cellulose as substrate there was a marked difference between nitrogen sources meaning that cellulolytic bacteria has a requirement for polypeptides or true protein for optimal growth. Key Words: peptidesamino acidsurea