Just wondering what you all thought was the best, or the differences in the two?  I'm wanting to feed an ionophore to my calves I am backgrounding.  I know Rumensin is approved for beef cows and I'm not sure about Bovatec, but that's irrelevant in this case.  I'm just looking to put weight on my calves.  They are 650 pound angus calves.  What are your thoughts? Thanks.