There is a record for the number of tennis balls held in a dog's mouth.

There’s a record for the number of tennis balls held in a dog’s mouth!

The world record is 5 tennis balls. It’s held by a golden retriever named Augie. He lives in Dallas, TX with the Miller family. The record was set in 2003, when Augie successfully held 5 standard sized tennis balls in his mouth. I don't know what's more interesting... the fact that Augie held 5 balls in his mouth, or that they keep track of these things.
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Read more at http://www.omg-facts.com/Animals/There-s-A-Record-For-The-Number-Of-Tenni/49327#WwBKdLwL5cLuOvkD.99