I don't get it.
Roy Rogers and Dale Evans are riding their horses on a trail. They turn a corner and startle a mountain lion. The lion rears up and bites at Roy, catching his boots. Terrified, Dale dashes towards town to get help. Roy draws his revolver and shoots the mountain lion dead. While his boots are torn, he receives nary a scratch. He mounts the lion on the back of Trigger and starts heading towards town.
Meanwhile Dale arrives in town and starts yelling for help. The sheriff gets his gun. The doctor gets his medical bag. Several townsfolk mount up and join the group. As they are about to set off Roy comes riding into town.
The sheriff looks at Roy, looks at the cougar, and looks at Roy's mangled boots. Then he says,
"Pardon me Roy, is that the cat who chewed your new shoes"?