Filde's technique is used for-

Filde's technique is used for Cl. tetani. Cl. tetanihas the ability to swarm over the surface of medium. Because of marked tendency to swarm over the surface of the agar, surface colonies are difficult to obtain. Filde's technique: After incubating anaerobically for 24 hours, if the water of condensation at the bottom of a slope of nutrient agar is inoculated with a mixed cell culture, subcultures from the top of the tube will yield a pure growth of tetanus bacillus.