Some morphological and biological changes in Cl.welchii types A, B and D accompanying the uses of some antibiotics

Various types of antibiotics were used for the iso- lat! on and pur1ficati on of differen t cul, turee of Ql. welc hii types A, Band D. The morphological, biochenical and bio-10~ical changes which occur in the organism itself I”,’r’ in itsproducts (toxins) were determined, these changes we.re stud Ie din a series of experiments, and the results proved that:1) 10 ug/ml of lincocin could be used for isolation and purification Of Cl. welchiitypes A, Band D.2) The shape of the o rg an Lsm as well as that of the clostridial colonies of either laboratory or clinically iso-lated strains of 21. welchii types A, B and D on blood agar plates did not change by the addition of the antibiotics to the cul tures.3) The diameter of the haemolytic z ona s .of colonies onp l.a t e s as well as the length of the organism of Cl. welchiitype A had been much decreased than those of the control(without antibiotics) by all the used antibiotics especiallyLincocin (10 ug/ml) and Kanamycin (250 ug/ml).