Lightning was a German Shepherd from a line of canine silent film stars. A grandson of Strongheart, Lightning was billed as "The Wonder Dog" and "The Marvel Dog". He began life as a runt but grew to be larger than average for the breed, and he was very intelligent. Lightning appeared in numerous movies.
From Wikipedia.
Speed
Lightning', a Dog
When Lightning Strikes
Lightning
Lightnin' Flashes
Lightnin' - the Super Dog
Lightnin' Strikes
Lightnin' - the Super Dog
Wings in the Dark
Lightning - Ken's Dog (uncredited)
Renfrew of the Royal Mounted
Lightning, Renfrew's Dog
Two in Revolt
Lightning - the Dog
The Case of the Howling Dog
Prince (uncredited)
Lightnin' Wins
Lightnin' - the Super Dog
White Fang
White Fang
Man's Best Friend
Lightning, Jed's Dog
A Dog of Flanders
Leopold, 'Leo' the dog
The Lure of the Wild
Shep the Dog