Looks a little like "Alf"
AKC has only recognized this breed since 2010
and their avg lifespan is very low at 7 years.
After the second word war, there were roughly only 54 breeding pairs left in the world. Most likely because they were eaten.
Aurther's father lived to be 12 and was healthy and mobile right up until his last month. He fell sick and refused to eat. I couldn't stand seeing him suffer any longer so I took him for a walk and put him down.
Leonbergers do well in a cold climate with healthy diet of deer meat. I hang a deer out back in the winter and lower it down every few days. Summer frozen pieces.
Aurther is 8 now and doing very well.