Not exactly news (except for the mechanism by which it happens).
For those of us who prefer really big doggos, it's a sad fact of nature. Labradors, for ex., never live remotely close to long enough - they go right from hyper puppy zoomies to arthritis. Not fair.
www.nature.com/articles/d41...
nature.com
Big dogs age faster than little ones — rogue ‘jumping genes’ might be to blame
Study of almost 900 dogs from roughly 120 breeds finds that rapid ageing of large canines is linked to changes in the epigenome.