never understood why larger breeds dont live as long, i know there are inherent issues with pedigrees which is one of the reasons i have normally gone for a mongrel, the one to the left of my sig pic is a german shepherd / collie cross who is around 20, still walking and active albeit a little slower and more elderly, the one on the right is again unknown pedigree as she was also a rescue dog but we suspect Malamute and probably wont live as long 🙁 currently only 2.
again sorry for your loss.