Ed,
A little off topic but I have a 50+ KG Male Rottie that is getting a little long in the tooth and as a result of this can be stiff in the morning. I have had him on this stuff for a while now

http://www.activexamerica.com/synflex/

I'm pretty sure it has been helpful, I also gave soem to my dad that has a really bad back (degenerative problem) and he seemed to think it worked better than his normal stuff.

Hope this helps

Merry Christmas

Simon