Abstract
Prophylactic tests of "Kiriyoi Disease" were performed by treating with the supplement of chlorophyll and cobalt, but no successful result has been obtained in 399 calves. Further experiments with oral administration of active vitamin B_<12>-producting strain were carried out, and marked prophylactic response was demonstrated in 344 calves. Finally, the acidic properties of the soil in the province were adjusted by treating with alkaline solution, and the increase of the strains was recognied.
