Inhibition of a Strain of Brucella abortus by Medium Filtered through Cotton

The study of cotton as a possible source of factors inhibitory for the growth of Brucella abortus was suggested by observations made at the Department of Agriculture's Animal Disease Station at Beltsville, Md. It was noted there that a potato-infusion agar medium clarified by centrifugation gave excellent growth of Br. abortus, whereas the same medium filtered through eotton was inferior in supporting growth of the organism. In order to determine the nature of the inhibition resulting from filtration through cotton, the effect of this procedure on the grow-th of a fastidious strain of Br. abortus on a simple and reproducible medium was studied.