Comparison of Loeffler's Coagulated Blood Serum and Blood Serum with the Addition of Sterile Ox Gall.

In 1913 Von Drigalski and Bierast reported on the results obtained by the comparative use of Loeffler's original coagulated blood serum plate medium and blood serum medium with the addition of sterile ox gall, in the isolation of the diphtheria bacilli. Drigalski's medium was prepared according to the original formula with the addition of 0.13 parts ox gall. They concluded from their work that the modified Loeffler medium rendered the isolation of diphtheria bacilli more certain and in many cases easier, due to the increase in the number of diphtheria colonies on the plates. Bulsing in 1914 repeated the work and compiled the results of various other workers in the use of Drigalski's serum medium. The following table shows the results collected by Busing.