The supplier said tripe was a must because of the probiotics???
As I said before, your supplier is trying to sell you tripe. A healthy dog has all the probiotics he needs to digest his food. Adding more has no benefit. Occasionally, for a variety of reasons, the probiotic count may get low. In a day or two, the probiotics will build back up on their own.
One more very important point. The probiotics in a cows stomach help with the digestion of grass. Not much use to a dog.
The sellers of tripe try to make it appear to have all these nutrients, sometimes even to the point of magical powers. If your dog has no digestive problems, he has no need for probiiotics. He already has them in sufficient number.
Tripe won't hurt your dog and it is good to feed because it does have nutrients but it is no more useful to the dog than any other part of the cow. There is no reason not to feed it, just don't expect it to be any better than muscle meat, bone, or other organs. :smile: