Lassie was my favorite show from the '50s, though I remember it from the 1960's more than the 1950's.

And don't forget Roy Rogers!

"The Double R Ranch featured Roy Rogers "The King of the Cowboys", his "Smartest Horse in the Movies" Trigger, "Queen of the West" Dale Evans, her horse Buttermilk, their dog Bullet, sidekick Pat Brady, and even Pat's jeep, Nellybelle."