Bio S.I. Jackpot ll equine probiotics supplies beneficial, soil-borne microbes (bacteria) found in nature to your horses. These microbes, which help to maintain the horses’ digestive systems, are contained in the soil and digested while they are grazing. Livestock kept in contained areas cannot maintain the proper amounts of these bacteria in their systems. Adding Jackpot ll equine probiotics will help them maintain that heavy level of beneficial microbes. Adding it to their drinking water or feed helps them better utilize feed, reduces stress caused by boarding/shipping/hauling, and helps reduce stress on horses from antibiotics use and worming.it.