NZ 601532 Disclosed is vacterium Bifidobacterium breve YIT 12272 (FERM BP-11320). Also disclosed is a primer for Bifidobacterium breve YIT 12272 (FERM BP-11320) as disclosed in the complete specification. Further disclosed is method for detecting Bifidobacterium breve YIT 12272 (FERM BP-11320).