i have used dds plus probiotics for my dog for 2 plus years and that stuff works really well if you want to do a probiotic but i say the less supplementation the better if you can do it with just food then do that and let the body act naturally if your dog is having diarhea then yes by all means do the probiotics as i really like the ones i use as they are non-dairy hypoallergenic and work - when i stopped dd for a while due to metacam incident she was a mess - put her back on them 1/4 and no more diarrhea since so they really work
Dds-Plus Capsules by U.A.S.Laboratories - UA-1010 - at The Vitamin Shoppe
i think human grade sometimes is better than the vet stuff