A Jack Russell and Shih Tzu mixed dog breed is called a Jack Tzu. The Jack Tzu is a friendly and alert dog with the coat of a Shih Tzu and the body size and shape of the Jack Russell breed.
The Jack Tzu is recognized by the Designer Breed Registry and the International Designer Canine Registry. The breed can grow to between 14 and 23 pounds. The breed's coat may shed heavily. The Jack Tzu is generally quiet when compared other dogs, except around other pets that bark. Care should be taken in feeding these dogs, as they overeat if allowed.