Solid Gold also sells supplements. You might check their website
www.solidgoldhealth.com
Also, I've seen a ton of supplements on
www.petfooddirect.com
I use human supplements with our babies.. We homecook for them, and I use recipes that say exactly how much to put in. I have researched all of the vitamins/supplements I give them, and I feel they are safe.
Dr. Pitcairn's Complete Guide to Health for Dogs and Cats