Optimisation of the time of milk sample decontamination with 0.75% cethylpirydinium chloride upon identification of Mycobacterium avium subsp. paratuberculosis.

Isolation of MAP from biological material, including milk, is very difficult. No matter how the fresh milk is obtained, it contains a certain number of rapidly growing microorganisms. Therefore, the decontamination process is applied in the methods of MAP isolation. Investigations were therefore undertaken to determine the optimal time of milk sample decontamination with 0.75% CPC. The experiment was divided into two parts: determination of the survival time of M.smegmatis and E. coli in 0.75% CPC and determination of the time of raw milk decontamination. The results suggest that the optimal time of milk sample decontamination is 15 min.