My 185 lb miniature horse just did a 5 day horse paste trial. One click a day for 5 days. (Not one click but one 250lb mark)
It was feeling fine before I started the trial, just wanted to see what effect if any.
I can attest that my horse had no adverse reactions and appears to feel no difference from day one to day 5.
When my healthy horse tried it, it was secretly hoping (I speculate) for a dramatic dump of parasites or something in its horsey toilet.
Nothing out of the ordinary happened.
My horse was (I speculate) mildly disappointed that it was already healthy.