A lot of glucosamine is sourced from shellfish. Do you think she could have a shellfish allergy? They make vegetarian glucosamine and joint supplements. http://www.swansonvitamins.com/q?kw=vegetarian+glucosamine+-+shellfish+free
I don’t think any supplements will conflict with kibble. You should be fine adding whatever supplement you decide to try right into her kibble. Sometimes herbs can have a strong smell (and taste I’m guessing) so you may have to add a little canned food or something else yummy to mask the smell/flavor.
