Coloured scanning electron micrograph (SEM) of Bifidobacterium animalis probiotic bacteria from the human large intestine (2.5% GA fix). Large group, close up of branches. The probiotic Bifidobacterium animalis is present in many dairy products, as well as dietary supplements. Once considered different species, there are actually two strains of this bacterium, now denoted as Bifidobacterium animalis subsp. animalis and Bifidobacterium animalis subsp. lactis. Magnification: x4,000 when shortest axis printed at 25 millimetres.