So many feed companies now add probiotics (ex: lactobacillus, etc) to their pelleted feeds........doesn't the pelleting process destroy these beneficial bacteria? Are they really viable enough to benefit our horses, and even if they are, should they be eating them everyday?
I add probiotics separately to my ancient pony's feed. The other horses don't get this supplement. The probiotic I use is specifically designed not to break down in the stomach, but to remain stable until it reaches the hindgut. I think it does help my pony keep weight on -- he has no hind teeth, and very little left in front. The feed store ran out of supplies of this probiotic for a few weeks this summer, and the pony dropped weight, which he regained once he had the product again.
I attended a grain factory tour and Q&A sometime back, led by a dietician. When asked the OP's question, she replied that the heat treatment (steaming) involved in pelletization of the feed probably killed off what was in there to begin with, and that the only reason they were in there was so the company could put it on the outside of the bag. Dietician was a sales rep for Nutrena, whose grain factory we were touring.
"The difference between genius and stupidity is that genius has its limits." Albert Einstein
That is my understanding as well. That is why when I feed probiotics, I use the tube Probios. I give it to babies to ward off this gross but necessary habit of eating poop, double dose if they show symptons of foal heat scour, and to mature horses after deworming.
According to a veterinary researcher I talked to last year, he'd yet to see a single food product labelled as having probiotics, that had enough in it to do a bit of good and he'd tested a lot of them in his lab. Buying them seperately, he would give a maybe to that but warned about how the levels were measured.