I have some of the cattle formula, but I would rather use the paste. My horses seem to think it tastes a lot better. The injectible is more trouble. As far as saving on waste, I am going to use a new syringe for each horse anyway, so it is not any different. I am with Joe on this; it's just not that much money. I am going for the easier route and using paste. (I only have 7 horses.) I have often found ivermectin paste for $2 per tube.