Stress-protective effects have been reported for M. vaccae NCTC 11659 and M. vaccae ATCC 15483^(T). However, it remains to be investigated whether also closely related rapidly growing environmental saprophytic non-tuberculous mycobacteria (NTM) species have protective effects against the negative consequences of chronic psychosocial stress. Therefore, the aim of the current study was to assess whether repeated i.g. administrations of a heat-inactivated preparation of Mycobacterium aurum …