I was recently listening to a podcast from The Horse (actually a Q&A webinar rerun) about Vitamin E. https://thehorse.com/188244/equine-essentials-the-importance-of-vitamin-e/
The guest expert was a big proponent of testing blood levels to determine supplementation needs (and response to said supplementation). She mentioned the test being I think in the $40-50 range, so it’s certainly not a silly idea towards optimizing your supplement purchases.
That being said, I know for some things prices take a wild jump when you cross that northern border (fecals, I’m looking at you). So just curious if any of my Canadian friends have had blood E levels tested, do you mind sharing the cost? Obviously it will vary somewhat vet to vet, but looking for the ballpark.