Is this safe for dogs? especially a pup? bought it online

Hello - CFU sounds for 'colony forming unit' - we're talking about bacteria here.  Different species contain different colonies of different bacteria, so it seems unlikely that even in the sort of cases where Probiotics are known to be useful, a catch-all 'pet probiotic' would be appropriate for all animals of all species at all ages, as this product appears to advertise.  I consulted an article by Nutritionist Marge Chandler, writing in the Veterinary Times; she suggests that probiotics can be useful in some diseases and even cites clinical evidence e.g. for diarrhoea in some groups of animals.  However, she says that probiotics need to be specific to the needs of the patient in question - and this does not appear to be the case here.  Probiotics should be targetted specifically. For me, the only sure way to know that a product is a) safe and b) helpful, is to see scientific evidence of this fact.  If no clinical trial is provided, the safety has not been proven.  I would always recommend against giving products where there appears to neither accountability for the safety or a relevant proven benefit.