Title: Effect of inhabitation by rumen protozoa on the nutritive value of protein in rumen contents.
Abstract: The nutritive values of protein, expressed as a modified chemical score, in two kinds of rations were compared with those of the rumen contents of faunated and defaunated goats given the two rations singly. The first, second and third limiting amino acids in the rations were lysine, methionine and histidine, respectively. In the case of the rumen contents of faunated animals, histidine and methionine tended to be the first and second limiting amino acids, respectively, whereas in those of defaunated animals lysine tended to be the second limiting amino acid. The improvement in the quality of protein in the rations in the rumen and the strict requirement of histidine for ruminants were discussed.