Source: https://www.amazon.com/Amazing-Probiotics-Dogs-Pure-All-Natural/product-reviews/B00KTY7W94/ref=as_li_ss_tl?ie=UTF8&reviewerType=avp_only_reviews&linkCode=sl2&tag=tdt01-20&linkId=6f5fc7b7fedb978bb1ac685edb95fa1d